Good mid and upper. Timing chains connect an engine's pistons with the intake and exhaust valves. I have seen throttle bodys for SBC with everything for 200. also would help out on MPG. The way it's running I don't doubt it will foul them all again this time. Here are some: Stalls at idle, stalls when I put the clutch in, stalls when I turn a corner, misfires, surges, no power, cuts out, no power at top revs, runs rough, etc. On V type engines having two manifolds, make separate tests on each manifold. Brian the TBI 454 chip man told me to go with the factory. sensor for $16 and haven't had a problem since. power loss on my chevy 454 in my truck question It was running rough when i bought it, took it home to do a tune up, found out the cap was cracked and it runs a drives smooth and good except for one part. But if the misfires get out of hand and occur too often, they can make the engine idle or run rough, stumble when accelerating, waste gas and fail an emissions test. Topped it off and ran it side to side until all was well and quiet. that is needed by the computer to run and control the fuel injection system. 7 bogs/backfires when I give it gas. I have a 88 k3500 with a 454 engine. Working on my boat. Chevy 3500HD w 454 motor shakes at idle - Getting an insane deal on it. this morning same deal, couple minutes of running great allowing me to move the car and back it up on the ramps then a flip is switched and it runs rough and stumbles. Runs when gas is poured into the TBI. 454 Throttle Body When chatting concerning desire automobiles, most consider those expensive autos that transform into a towering robot. After it warms up if it is sitting idling it runs rough as crap and then dies. All of the sudden one day it was really hard to start then ran fine, the next time I tried to drive it it would start and run for about 4-5 seconds then die. Very rough cold idle. I've checked the connectors at the dist and they are plugged in and fine. My father in law's '91 Chevy was running poorly, so we put new plugs, wires, cap and rotor on it, and it's running better, but it it still surging at idle. The following information contains troubleshooting testing procedures for engine surges problems [i. The way it's running I don't doubt it will foul them all again this time. back to the tank or in the engine. Congratulations to ThirdGen. In most cases this is only done if you have modified the internals of your engine or you have swapped a larger throttle body onto your vehicle. GAS MILEAGE. Suburban stalling issue. I brought the RV back to my friends' shop and if I remember correct we replaced the ignition module the ECM had fried and that was that. The intervals of opening and closing are very short -- from one-fifth of a second when idling to two hundredths of a second at 5000 rpm -- so small problems can seriously affect engine performance. Find out what type of fuel is in the boat’s fuel tank. Engine problems on a 1989 gmc r3500 with a 454 tbi. Asking for any and all help. 1 Million parts in stock - Fast Free Shipping on orders over $99. 91 350 TBI rough idle and no power at all. Was still running rough after that so I sprayed for vacuum leaks with some WD. If its running rough when cold it may be because of open loop its running in, the computer will use presets for fuel delievery, any vacuum leak or fuel delivery issue, the computer will not compensate for untill it gets into closed loop, probably a few minutes of running on that old of a vehicle. Worked when it was on the truck, but wouldn't die when the passenger idle screw was turned all the way in, so I thought the metering block was plugged. Brian the TBI 454 chip man told me to go with the factory. It will run on 91+ unleaded fuel. 7L, TBI, 260K on the motor at idle, it's extremely high, around 1600-1800 RPM's when put it drive, drops down to about 1000-1200 (still way too high) I've put a new IAC (idle air control) valve in, checked my timing. 99 k3500 dually 7. if clogged with carbon or not adjusted right it will die. Running with stock programming with a low idle speed setting combined with the fact the chip is designed for 20-21″ of vacuum at that idle rpm with a cam upgrade which typically drops the vacuum to 18″ or less will cause the motor to run too rich which will spawn a high idle speed where the motor will then lean out and rpm drops and repeat. Used them to haul my BGF up and down the coast. The milky oil burned clean after smoking a while. I have a 1992 34 Silverton with Crusader 454 XL's. Moved everything around. 7 TBI Cold start flooding issue Hey gang new here and in need of some help. Truck ran fine never had problem until now truck cranks fine and strong also fuel pump starts for 2-3 seconds then turns off left for 2 days came back would not start. 05 on 200 hp NOS plate (w/1. Idle Problems With Performance Camshaft I have read almost every article and threads on the Internet about this problem, but haven't found a working solution for my setup. 7 TBI motor dis assembled spun a rod. When I start it in the morning it starts but runs and idles very rough. It runs great as long as I don't get stuck in traffic and have to idle for more than a couple minutes. I am just tired of getting stuck on hills and running poorly on rough gound. In my neighbor's Blazer, the PCM wasn't even registering a P0300, but it was obviously running very rough (at idle that is). 00 >> click for more images >> propane conversion kit for onan generator with ford 292 onan generators using ford v8 292 engine w/2 3/4 $595. 5 volts going to the fuel pump. I'm thinking of doing the same thing, new 350 in my 91 Sierra 4x4, considering it has 151,000 plus miles on it, mostly hi-way. 00 in the trader. I have seen throttle bodys for SBC with everything for 200. The distributor rotor IS pointing to #1 wire at TDC. it is a throttle body Carb. The intervals of opening and closing are very short -- from one-fifth of a second when idling to two hundredths of a second at 5000 rpm -- so small problems can seriously affect engine performance. im trying to sell this truck, but i cant get it tuned up. with a 454 c. that has a rough idle, and will bog down on acceleration. Every car lover wants to drive a vehicle that goes faster than any kind of race automobile on earth. Once the auto choke begins to come open it smooths out. Mileage down from 13avg to around 8. :grrrrrr:. Rough idle but otherwise runs fantastic. All others may contain a boat load of trash (mainly rust and build up from old gas). Join millions of people using Oodle to find unique used cars for sale, certified pre-owned car listings, and new car classifieds. Well that gas is long gone and it still misses. Motor was a beast with a 950hp carb. it wont do it every time but most of the time. This page is for information about GM Throttle Body Injection EFI swaps. At some point it will begin to gain power but still runs rough. Having a problem with the engine. The 90s were some rough years for smog the engines were turds. GAS MILEAGE. My Engine Turns Over OK But It Won't Start If your engine won't crank or turn over, go HERE. Played with the idle screw to no avail as well. Come to find out that the coolant temp. 93' K5 Blazer 5. The fix: Check and repair the cooling system. GM TBI on an AMC 360/401 motor FAQ. Find out what type of fuel is in the boat’s fuel tank. 00 >> click for more images >>. Very rough cold idle. MERCRUISER HORN WARNING SYSTEMS 90-898301003 JUNE 2007 Page 5 / 10 Models All MEFI-3 V-6 and V-8 Sterndrive and Inboards 4. Re: 89 454 tbi running like crap okay, I pulled the IAC and the plunger, node, has a minor wear mark on it from ,I would say, being the original piece. Problem CONDITION POSSIBLE CAUSE CORRECTION 7) Idle cut-off solenoid not working. I have a 1992 Chevrolet K2500 350 tbi that idles high about 1200 to 1500 rpm sometime's will idle about 800 rpm. 24-standard -- -- Table structure for table `archive` -- CREATE TABLE archive ( ar_namespace int(11) NOT NULL default '0', ar_title varchar(255) binary NOT NULL default '', ar_text mediumtext NOT NULL, ar_comment tinyblob NOT NULL, ar_user int(5) unsigned NOT NULL default '0', ar_user_text varchar(255. GM 454 Engine Fuel Systems: The following information hopefully will help those that own and love the classic Coaches and wish to keep them running with the performance they were designed to provide. This page is for information about GM Throttle Body Injection EFI swaps. left it alone because it's too cold out. 0 tbi motor has low compression and runs a low operating temp. -- MySQL dump 9. there seems to be way to much vacuum on the line that runs to it from the TBI. I have a 1995 Chevy C3500 crew cab with a 454 and an 4L80-E transmission. This is a complete ready-to-run hot system when you choose our Fast Track Startup option with this Turnkey Package. I had a Chevy Silverado with the 5. One thing I do know that TBI engines do is hesitate from the EGR opening too soon. Car (or truck or mini-van) seems to run ok above 30 miles and hour but once you come to an idle, the engine barely stays running. Chevy 3500HD w 454 motor shakes at idle - Getting an insane deal on it. 0Gi (TBI) which seems to be running very rich. It seems to have a long crank time before starting sometimes it starts and dies. Has a Rough Country 6” lift, but pulled one spring out of the front and I believe two leaf springs out of the rear to get it closer to “show height” and to get it to ride. When first started in cooler weather the engine misfires, runs rough. ive changed the plugs and the. i have run these with 750 holly carb and the stock throttle body is rated at 800 i think i could be wronge any way. Come check out all the different pictures and details about 19 Ways to Diagnose Car Engine Problems, and so much more. On V type engines having two manifolds, make separate tests on each manifold. Shut it down quickly, pull the spark plugs and put two squirts of motor oil into each cylinder. Get a huge boost for your '88 - '98 Chevy / GMC 1500, Tahoe, and Suburban with Rough Country's all-inclusive 6-inch Suspension Lift. His hands were always dirty, but the MAP sensor looks old. No MAF sensor or O2 sensors on this TBI 454 engineit's a 1ton. I thought I'd just order a catch all of parts off Amazon prime that it could be and send. Sign In my old truck is randomly sputtering. TBI stands for throttle body injection, which is available on certain combustion engines. If you have the throttle just barely open it will smooth out until it upshifts then it does it again until the rpms build. com The intake is Edelbrock for a carb with an adapter form a 454 TBI engine. Engine idles rough. 1990 454SS TBI rough idle, but under. I was concerned with the performance of the Sniper to run this motor. The EGR valve is a component of an automobile’s exhaust circulation system that reduces pollution-causing emissions. It doesn't want to idle and dies when you put it in gear. It had slightly reduced power compared to the L29 454 and used a different PCM. It is stallish, and surges in neutral or park at idle (revs, then drops off, then revs again). Smoother, quieter, better throttle response, etc. 7 with Thunderbolt V Ignition, 2 barrel Mercarb. When this happens the check engine light comes on. Runs when gas is poured into the TBI. My TBI 454 has been running rough. Fine tuning could be done once a baseline start was established. This bubbling is normal if you have air trapped in your system, and is caused by the air escaping as it reaches the area of the open radiator cap. 11 to 15 RVP (cool to cold weather) fuel will change from liquid to a vapor at lower fuel temperature than 8 to 10 RVP (warm to hot weather) fuel will. This harness will also work on an `86-93 4. Rough idle but otherwise runs fantastic. Another question I have on the external fuel pump whith the engine running at half throttle the pump has flow the full 1/4 inch diameter but only flows out about 1/2 inch. The engine is a 4-bolt seasoned heavy duty Chevy Small Block, hand picked. It stumbles badly off idle and at mid throttle, but once up and going seems to run fairly smoothly. I have a 1992 Chevy Dually with a 454. When shifting into drive, engine runs at idle rpm, when throttle is pushed down to come off idle, engine coughs & dies. chevy forum at Car Dealer Forums; Truck runs great, but recently when the engine comes off the enriching circuit. 4 GSI/DP Volvo Penta, 454 engine 1998 27 foot Doral, well last week I idled out of the bay which it ran just fine for about five miles then I pulled back to do a little trolling, after an hour I decided to pick it up and move to another spot and noticed that I couldn't get on plan or accelerate over 2. CAR RESTORATION HOW TO How to Replace A Distributor Without Going Crazy. Admitadley, I know little about throttle body injection(TBI). An area often overlooked is the performance of the fuel system not while the engine is running, but when it is shut off. On our 1992 P30 454 TBI the fuel filter getting stopped up acted that way. With the exception of firewall clearance problems in various vehicles, this should apply to swapping most any GM points type distributor to HEI. my car lost the bog, and was running tops after that. It ran great for 2 weeks then started to go down hill,to day i pulled 2 plugs 1 was. 19 Answers. 3L TBI - Idle troubles within the Automotive Support forums, part of the Tech Support Forum category. Could it be a O2 sensor or fuel filter. Very hard to maintain an idle now on the truck and the conical spray pattern is thick and constant when the truck is running. Unless the bubbling is excessive, continue to let the engine run at idle for a few minutes once it reaches normal operating temperature, then shut it down. 7 V8 GM Crate Motor. Recently rebuilt the 454 in my 1990 TBI Burb. Re: 88 Chevy K3500 454 TBI. A few weeks after I bought the truck I filled up to go on a long road trip. I have a 1995 Chevy C3500 crew cab with a 454 and an 4L80-E transmission. The fuel burns and powers the car. You really need to get with one of the tuners on this site , datalog and let them help you get your vehicle to run right. You'll get lots more people looking at your question that have direct experience with this kind of truck. I had a Chevy Silverado with the 5. The electronic throttle body fuel injection system is a fuel metering system with the amount of fuel delivered by the throttle body injector(s) (TBI) determined by an electronic signal supplied by the Electronic Control Module (ECM) or Powertrain Control Module (PCM). I have an 88 TBI- 454. mc22298 hyd 4 222 232 297 307. The first thing to check for here is a vacuum leak. MPG is also down. Great mid range horsepower and torque. Another question I have on the external fuel pump whith the engine running at half throttle the pump has flow the full 1/4 inch diameter but only flows out about 1/2 inch. Find out what the RVP of the fuel in the boat's fuel tank is. The 454 engine in my 1984 Itasca runs really hot but perhaps it is normal for the engine. 4 GSI/DP Volvo Penta, 454 engine 1998 27 foot Doral, well last week I idled out of the bay which it ran just fine for about five miles then I pulled back to do a little trolling, after an hour I decided to pick it up and move to another spot and noticed that I couldn't get on plan or accelerate over 2. If its running rough when cold it may be because of open loop its running in, the computer will use presets for fuel delievery, any vacuum leak or fuel delivery issue, the computer will not compensate for untill it gets into closed loop, probably a few minutes of running on that old of a vehicle. Motor was fully built in 2015 and has rough 1998 Z-71 Big Block 454 (league city) $10000. My chevy 1987 chevy Scottsdale with a 350 tbi sometime runs smooth then sometimes runs like its running with half the power or less like it has bad gas or something. The hardest part was the routing of the fuel lines and finding a good place to mount the fuel pump and filters. Brian the TBI 454 chip man told me to go with the factory. Опубликовано: 1 сен 2012 ; If your chevy gm tbi is running rich this will help you trouble shoot it and fix it Don't Forget to Subscribe today for more fact or fiction, diy ,how to car repair,spooky or funny videos uploaded weekly. When you stop it will just about stall then there is very little power when you take off. If its running rough when cold it may be because of open loop its running in, the computer will use presets for fuel delievery, any vacuum leak or fuel delivery issue, the computer will not compensate for untill it gets into closed loop, probably a few minutes of running on that old of a vehicle. When the motor is cold, it will start right up, but will lump at idle and feel rough because the choke provides a too rich a mizture and overloads the engine to the point where it wants to run rough, almost to the point of stalling. Runs when gas is poured into the TBI. How could spark plugs become black with soot? Dear Tom and Ray: I am hoping you can help with a problem I am having with my wife's 1967 Camaro Convertible. It gets slighty worse when engine is hot. 91 350 TBI rough idle and no power at all. So, I took the truck to the local shop where I worked a few years ago as a full service attendant while in highschool. Chevy Suburban/Tahoe Rough Idle and Stalling The vehicle runs great at speed and if you hold your foot lightly on the accelerator it will not die. 454 And A 4-Speed: 1974 Corvette Jamie Palmer Before you start writing that email telling me I'm wrong on the year, yes, this is a 1974 car, it's just wearing a lot of 1982 parts. Engine Hesitates, Stumbles, Lacks Normal Power The computer uses this information to determine how much fuel is needed to maintain the correct air/fuel mixture, and when extra fuel is needed if the throttle suddenly opens wide. I cleaned it really good and the chamber it bolts into with tbi/carb cleaner. Had recently filled up and thought it might be bad gas. RPM Pre-Set: We want to Make Sure The Carburetor Curb idle is Pre-Set, Not to Low and Not to High, A Low Curb Idle Setting will Leave the Engine Running Rough Causing a Poor Running Engine, However a High Idle will Leave the Engine Racing Causing a Rich Running Condition. Spectre Performance Pulley Sets are precision engineered from high quality materials to give your engine a clean and professional appearance. 7 Idle surging,stalling in the alt. Everything else has turned out great. 1994 Chevy C1500 5. When engine hot on the highway, when second venturi of carb is opened the engine seems to die momentarily. As the title states, under no throttle my 1990 454SS 127K runs like it has a lumpy cam, but under throttle it runs OK. Why does a 1993 Chevy pickup with a throttle body injected 350 run rough just off idle or under almost no load? As long as the 350 is a fuel injected engine / TBI / Throttle Body Injection. i agree about 90 % of chevs will run better with vacum advance. if its a 350 tbi then it could be the idle air control sensor. Bruce Recently returned from long trip and our 87 Coachmen started running rough under load. Including a Large Selection of New, Used and Surplus Engines for Sale. Like the title says I have a 87 C30 w/454 TBI and 400th. The throttle position sensor, TPS for short, is a sensor that is used in an internal combustion engine. I took it to a certified merc mechanic and took him for a ride in it. Print See Figure 1. Help please! I have a 1994 winnebago warrior with a Chevy 454 tbi. Chevy TBI idle problems. Rough idle, stalls when in gear. What complicates a rough idle/misfire condition is having the PCM not register any specific misfire codes. My TBI 454 has been running rough. After it heats up for 20-30 minutes runing at 32000 RPM in gear. 3L (W) L35 Engine. Its a very strong engine, lots of poop and super simple, runs better than any stock Vortec I ever drove. Seemed to be lacking some power and idled a little rough in gear and hot. S-10 Cranks Wont Start. Stopped running. If its running rough when cold it may be because of open loop its running in, the computer will use presets for fuel delievery, any vacuum leak or fuel delivery issue, the computer will not compensate for untill it gets into closed loop, probably a few minutes of running on that old of a vehicle. It may well be that these events are the hesitation & stumble problems described in this article. Street driven everywhere including at 75 MPH on freeway. It seems to have a long crank time before starting sometimes it starts and dies. The distributor may develop internal faults. Find 454 Engine in Canada | Visit Kijiji Classifieds to buy, sell, or trade almost anything! New and used items, cars, real estate, jobs, services, vacation rentals and more virtually anywhere in British Columbia. The strange thing is, the truck seems to run a little better with the plugs gaped at. I have checked my wires 10 separate time to make sure they are in the right position, Ive yanked them off and put them back on according to the order and still no improvement. You will also need the proper tool to loosen the retaining screws. low clearance dual fuel propane & gas kit engine high hp horsepower v8 454 bolt on duel fuel for high horsepower engines, will work with carburetor with a 5-1/8 $1475. The milky oil burned clean after smoking a while. A 30 % increase in horsepower, torque and fuel economy is seen over carburetion. The 90s were some rough years for smog the engines were turds. If its weak, it will cause all kinds of popping as well. I would like to ask some of you to take an educated guess at this problem(s). 7 Idle surging,stalling in the alt. My TBI 454 has been running rough. Stopped and the whole truck was shaking, reaked like fuel. 8 depending on what im doing. Unless the bubbling is excessive, continue to let the engine run at idle for a few minutes once it reaches normal operating temperature, then shut it down. Suburban stalling issue. 6:1 roller rockers. Final note: Im NOT a flight or aerodynamic engineer etc but have owned all brands and shapes and sizes of Class A and Class C over 30 years (was a used RV dealer at a time) and despite the carb and distributor and exhaust tuning and TBI or EFI and Class C or Class A, 10 MPG is the best I ever got (with current Class C with Chevy 454 Vortec and. Two new injectors but wont release fuel spray. I own a diesel 80-series land cruiser. 5:1 comp ratio when it comes to speed pro-hypereutectics, a high-volume oil pump, a brass deep dish, and hardened push rods, allowing for durability and optimal engine performance. Continue rotating the motor gently till you can just turn the intake pushrod. If you have a scan tool, all you need to do is pull up the TPS voltage data. During idle it would sound as if it were about to shut off but it wouldn't. What would cause TBI engine to sputter, hesitate, skip and misfire/backfire. Discuss 1990 TBI 5. When i first start the truck it slowly rises from 1000 to 1500 rpm then comes down after five minutes to 1000 rpm then when i drive it for a few minutes then it starts idling at 1100 rpm when the truck is in drive. BASIC RPM 3200-6700 Strip Oval CD244-11 975900 99250-16 244 252 280 288 106. Fuels containing alcohol are more likely to vapor lock on hot days. It has 200k on it, and has a horrible low throttle input miss and a high idle at times. com has a wealth of information RE GM TBI systems. 90 and older is particularly bad and that is largely due to NO OVERDRIVE. The truck has low miles ( less than 78 ,000) and shows no symptoms ( no idiot lights , no leaks , no rough running). This harness will also work on an `86-93 4. 7L TBI and when I replaced the starter, I found that the knock sensor's ceramic fitting had broken and the wire came off- it was sluggish, but it didn't knock excessively. I poured gas in carb and 454 started up and sounded good but not will stay running do to no fuel from tanks. Suburban 1993 2500 -454 / It runs rough on start up and then leans out and then the motor idles faster. Smoother, quieter, better throttle response, etc. Car and Truck Fuel Injectors. It turned out to be a $10 fix in our case. why can't I just get my vehicles to run right for one week? I think the oil pump crapped out in the xj, so now I'm driving the 93 chevy, heres whats going on: 1993 chevy k1500 - 5. Further information from the customer indicated that the truck misfired the worse in drive, not overdrive, at light to normal cruise around 2000 rpm to 2500 rpm. Runs when gas is poured into the TBI. First thing you do is pull the code form the engine. I had a Chevy Silverado with the 5. This bubbling is normal if you have air trapped in your system, and is caused by the air escaping as it reaches the area of the open radiator cap. The fix: Check fuel pressure with a fuel pressure gauge. It stumbles badly off idle and at mid throttle, but once up and going seems to run fairly smoothly. that has a rough idle, and will bog down on acceleration. I have a 93' Chevy K5 Blazer that developed a cold start issue just recently since the temps have started hitting the 40's at night here in Eastern Washington state. 3L TBI - Idle troubles. 546 107 117 2500-6000 rough 2148 n. 7 bogs/backfires when I give it gas. A few weeks after I bought the truck I filled up to go on a long road trip. It runs rich when it is running rough. by Abdul-Wahab April 25, 2019 Abdul-Wahab April 25, 2019. But if the misfires get out of hand and occur too often, they can make the engine idle or run rough, stumble when accelerating, waste gas and fail an emissions test. 7L) engines. We Can Promise You the Curb Idle will be Set for a Plug-N-Play Setup. I started using ATF (clean ATF straight out the bottle] in my fuel. What might seem like a trivial task to most hobbyists, removing and replacing (or reinstalling) a distributor can easily degenerate into a time-consuming, frustrating job that can result in great difficulty in getting an engine running properly. Here I will try and address the common misconceptions and frequently asked questions in regards to upgrading to TBI (Throttle Body Injection) for your AMC 360/401 motor. My 88 didn't have anywhere else to ground other than the thermostat and the wire wasn't long enough anyway so they all went to the thermostat stud. Sometimes it starts and surges before dieing and other times it starts and seams to idle fine. It was telling the computer it was -30 degrees and filling the throttle body with fuel, flooding it out. 7 bogs/backfires when I give it gas. Bruce Recently returned from long trip and our 87 Coachmen started running rough under load. After you have properly adjusted the stop screw and the TPS you will need to look at the dash pot. , that only affect the efficiency of the spark, but the. The air/fuel ratio can also be affected by changes in altitude. 91 350 TBI rough idle and no power at all. I have a 1992 Chevy Dually with a 454. What Causes Backfiring on Acceleration? Backfiring during acceleration occurs when ignition takes place in the intake or exhaust instead of the combustion chamber. 1994 Chevy C1500 5. There are many reasons why an engine won't start. Final note: Im NOT a flight or aerodynamic engineer etc but have owned all brands and shapes and sizes of Class A and Class C over 30 years (was a used RV dealer at a time) and despite the carb and distributor and exhaust tuning and TBI or EFI and Class C or Class A, 10 MPG is the best I ever got (with current Class C with Chevy 454 Vortec and. It presently has something on the order of 120k miles on it, and recently has begun running badly. After it warms up if it is sitting idling it runs rough as crap and then dies. I noticed the drivers side injector was spraying/ spitting kinda sideways and noticed gas would hit the center part of tbi unit and then drip. TBI is a fuel injection system that uses a pair of injectors mounted in a single housing that is mounted and functions much like a carburetor, except that the injectors replace the venturis, jets, air bleeds, fuel bowls, and floats. It will run on 91+ unleaded fuel. there seems to be way to much vacuum on the line that runs to it from the TBI. 536 MECHANICAL - Rough idle suits strip or oval track. Played with the idle screw to no avail as well. 0L) and LO5 (5. The distributor may develop internal faults. That fixed the rough idle and it drove fine for a day or two. I installed an adapter and fuel pressure gauge at the tbi and converted the regulator to an adjustable type. A few weeks after I bought the truck I filled up to go on a long road trip. 7 V8 GM Crate Motor. The mechanic found a shorted wire that was preventing the injectors from firing. Problem is the boat run perfectly for about 20-30 minutes and then starts to loss power, backfires and while not run over approx. After you have properly adjusted the stop screw and the TPS you will need to look at the dash pot. I cleaned it really good and the chamber it bolts into with tbi/carb cleaner. It was telling the computer it was -30 degrees and filling the throttle body with fuel, flooding it out. 00 in the trader. 00 >> click for more images >> propane conversion kit for onan generator with ford 292 onan generators using ford v8 292 engine w/2 3/4 $595. 4L VIN N TBI. My 1992 GMC S15 4. This is in 5 degree increments, at least, in the case of marine engines prepared by Indmar for Mastercraft, Malibu, Supra/Moomba. , that only affect the efficiency of the spark, but the. Replaced: Plugs Wires Cap Rotor Coil Coolant temp sensor Cleaned pcv,egr and checked for vacuum leaks Adjusted/advanced timing Removed cat Still have rough idle, and slight smell of unburnt fuel. Rough idle but otherwise runs fantastic. Find 454 Engine in Canada | Visit Kijiji Classifieds to buy, sell, or trade almost anything! New and used items, cars, real estate, jobs, services, vacation rentals and more virtually anywhere in British Columbia. The way it's running I don't doubt it will foul them all again this time. they are completely random. Different owners seem to describe this problem using a variety of expressions. Connect the vacuum gauge hose as close to the intake manifold as possible and start engine. It turned out to be a $10 fix in our case. 1992 S-10 Pickup V6 4. Re: 88 Chevy K3500 454 TBI. ) And runs High 7's w/400hp plate, then switching to 400 hp fogger sys in 2nd gear (w/1. Ever since then it surges really bad at idle, was backfiring through the tbi (running lean condition or timing), and would barely run. The intervals of opening and closing are very short -- from one-fifth of a second when idling to two hundredths of a second at 5000 rpm -- so small problems can seriously affect engine performance. Working on my boat. I know, im just suggesting. run the truck with a fuel pressure gauge on it. Could it be a O2 sensor or fuel filter. Well that gas is long gone and it still misses. What would cause TBI engine to sputter, hesitate, skip and misfire/backfire. Rough idle, stalls when in gear. When engine hot on the highway, when second venturi of carb is opened the engine seems to die momentarily. the gauge should be still the same psi. Looking for help please, 1998 5. 88 k3500 454 tbi ACDelco Plugs Blue. This bubbling is normal if you have air trapped in your system, and is caused by the air escaping as it reaches the area of the open radiator cap. TBI is a fuel injection system that uses a pair of injectors mounted in a single housing that is mounted and functions much like a carburetor, except that the injectors replace the venturis, jets, air bleeds, fuel bowls, and floats. Re: hard start 98 chevy vortec 454 December 11th, 2011, 12:57 AM leakie injector would do it. The truck is now running but very rough. Generic TBI Fuel Injection Block Diagram & Acronyms Individual Components and Their Function We have covered the block diagram and acronyms and are now ready to take a look at the function of the individual components, and some general information about them, and how to procure them. if clogged with carbon or not adjusted right it will die. Recently rebuilt the 454 in my 1990 TBI Burb. Fuel Injection – TPI, SFI, TBI, SPFI, MPFI LT1, LS1 Wiring.