How to fix a 1990 Chevy 5.7L TBI fuel problem?

It ran long enough to drive up on the trailer while under its own power and it also drove off the trailer on its own power (not that same day I brought home) but you did have to keep foot on throttle otherwise it would stall out and not start again until the next day. 1. New Fuel pump 2. New Fuel filter 3. New Fuel pump relay 4.

What causes the fuel pump to not start?

The fuel pump is running and delivering normal pressure to the engine But, with all that working your engine still will not start. So, the most likely cause, is that the fuel injectors are probably not opening. The (PCM) uses the trigger signal from the crankshaft position sensor; and/or camshaft position sensor to pulse the injectors.

Why is my TBI fuel injection light on?

Troubleshooting your TBI Fuel Injection System Most of the problems encountered while installing your fuel injection system or after a time of operation are very simple. If your check engine light is on you more than likely have a hard fault meaning something is grounded out, unplugged, operating out of range or has gone bad.

What is the TBI code on a 1990 Chevy truck?

Consult a service manual or see below for any check engine light code definitions. You can use a late 80’s or early 90’s GM TBI definition. If you have access to a scan tool use a hook up for a 1990 350 cu. in. 5.7L Chevrolet truck. For some scan tools enter VIN 10th“L” 3rd“C” 8th“K”.

Is there no fuel from injectors to start truck?

No fuel from injectors to start truck. When I try and start my 93 Chevy Cheyenne k3500 no fuel come out of the injectors. If I use starting fluid the truck starts and the injectors work great. Has died a couple times while driving, but mostly runs fine and then won’t start one turned off.

What should fuel pressure be on a TBI fuel injection system?

Fuel Pressure is critical to the operation of a fuel injection system. Always check to insure that you have the proper fuel pressure. Fuel pressure should be a constant 10 – 15 PSI on a TBI fuel injection system and is typically around 12 – 13 psi. Higher pressure than 15 psi indicates that there is an issue with the installation.

Why is my Chevy k1500 not getting spark?

Chevrolet k1500 getting spark to all plugs, gas to TBI, continuity from ECM to injectors, but no pulse to injectors. Please help! Every possible part I could test passed just wondering if it is an ECM problem?

Can a 1997 Chevy c1500 5.7L start?

1997 Chevy C1500, 2WD, 5.7L won’t start – cranks fine. No codes – good fuel pressure ( 60+ psi – new pump), good spark, 1997 Chevy C1500, 2WD, 5.7L wont start – cranks fine. No… It will not start. I changed the fuel filter and fuel pump It will not start.

Why does my 1990 Chevy Silverado not start?

My 90 would not start if the vacuum line to the MAP sensor was disconnected. The MAP is located behind the TBI. Be sure the vacuum hose is in good shape. Mine has to be replaced as the glue no longer worked and it leaked. If you have a vacuum pump, make sure the MAP can hold a vacuum or it needs to be replaced.

Is there a problem with my 1990 Chevy truck?

I just recently purchased a 1990 Chevy 2500 single cab long bed with the 350 tbi that has been D.O.T inspected until 2018 in MN. The issue – it has a fuel delivery problem and the previous owner was fairly certain that it needed a fuel pump and I wasnt surprised cuz ive had to do that with past 90s gm trucks.

How to check fuel pressure on an 87 TBI?

* Check the 3-amp INJ fuse and the 10-amp ECMB and ECMI fuses located near the bottom of the fuse block. * Measure the fuel pressure. For ~2 seconds after the ignition is switched ON the fuel pressure should be constant and unvarying between 9-13 PSI, typically ~11 PSI.

What to do if you have a fuel pump problem?

1. New Fuel pump 2. New Fuel filter 3. New Fuel pump relay 4. New Fuel pressure regulator 5. Used fuel injector wire connecters 6. Used fuel injectors (from junkyard may not be in working condition)

What causes a fuel pump to go out?

Make sure you test fuel pressure the pump could be weak. usually the pump goes out for two reasons someone forgot to change the fuel filter and the pump struggled to pump the fuel through a plugged filter or someone ran the fuel too low in the tank.

Why is my fuel injection system plugged in?

The electric fuel pump installed for a fuel injection system will draw considerable more volume of fuel from your tank than your old system did. If there are any contaminants in the tank this many times will plug up or greatly restrict the flow of fuel to the system causing many issues. Step by Step Troubleshooting guide.

Where is the fuel injector on a GM TBI?

The GM TBI (Throttle Body Injection) system uses a pair of low pressure fuel injectors mounted above the throttle body opening. Unlike a port fuel injection system, that sprays fuel into the intake manifold runner just above the intake valve, the injectors in this system spray fuel directly into…

How to test the fuel pump on GM TBI fuel systems?

One method involves removing the fuel filter and using an adapter, that has a Schrader valve on it, in its place. You then connect your fuel pressure test gauge to this adapter. The other method is to use an adapter between the throttle body assembly and the pressure line.

What are the facts about a 1990 Chevy Suburban?

This page is dedicated to facts, specifications and statistics specific to the 1990 Suburbans only. Much of the information applies to 1989-91 Suburbans as well as there are very little changes within the last 3 years of the 7th generation. To cover all the years of the Suburban starting from 1935 would be a major undertaking.

How many spline did a Chevy Suburban have?

With a T400 or 4L80E trans or 5 speed, it will be 32 spline. There was only 1 available transfer case in 1990, the NP241C.

Why is the fuel pump on my TBI not working?

This confirms that the cause of your TBI equipped pickup’s ‘no start’ condition is caused by a lack of fuel. Now, I usually take one more precaution, before condemning the fuel pump as bad and this is to check that the fuel pump is getting 12 Volts as the engine is cranking.

When did the GM TBI fuel injection system start?

Same can be accomplished with any TBI system from mid 1980s to 1995 and all information here will lead you to the right choice! Best thing to do is go to junkyard and find a motor similar size as yours and get the complete system and parts.

What are the symptoms of a bad fuel pump?

Symptoms Of A Bad Fuel Pump. Where To Buy The Fuel Pump And Save. TEST 1: Using Starting Fluid. TEST 2: Fuel Pressure Test With Gauge. Which And Where To Buy A Fuel Pressure Gauge. More GM 4.3L, 5.0L, 5.7L Tutorials. You can find this tutorial in Spanish here: Cómo Verificar La Bomba de Combustible en Los Sistemas TBI (at: autotecnico-online.com ).

How to troubleshoot your TBI fuel injection system?

Is there an injector pulse while cranking the engine?

The engine will run if you either spray starting fluid down the throttle body or hook up a remote start switch. If you use the key, there is no injector pulse while cranking. As you let go of the key and return it to the run position, the injectors give one squirt.

Can a GM throttle body injected TBI be used?

Many still out there with TBI vehicles needing help getting more modern power levels and fuel mileage from older GM throttle body injected vehicles without going to the process of rewiring the vehicle to run a more modern fuel injection system.

Why is there no pulse from the injector?

Used all original electronics and tbi. New wires, plugs, cap, rotor, fuel filter,etc… have spark, have fuel at the back of the tbi. No pulse at all from either injector?

What should the voltage be on a fuel injector?

The wiring harness will have two terminals that the prongs on the injector insert into. One will be connected to ground and will read 0 volts. The other should read around 12 volts. Step 5: Repeat with all injector wiring harnesses. Leave the ground lead in position and test all of your injector wiring harnesses. They should all be around 12 volts.

Used all original electronics and tbi. New wires, plugs, cap, rotor, fuel filter,etc… have spark, have fuel at the back of the tbi. No pulse at all from either injector?

What should the TPS be on a 1990 Chevy 5.7L?

The TPS should go from >0 to ~4.8 VDC (IIRC), for example mine goes from 0.45 – 4.39VDC at WOT. I know they say it should be ~ 0.58 – 0.59VCD but, that’s close enough for me.

What makes a’91 TBI 350 surging at idle?

It basically almost dies out, and then surges back to life (probably a little higher than normal idle), then repeats continuously until you apply some throttle. If I had to guess, I’d say it’s a dirty throttle body, or possibly injecters. If it is one of these, what would be the best way to clean them?

What makes a 91 Chevy surging at idle?

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. It basically almost dies out, and then surges back to life (probably a little higher than normal idle), then repeats continuously until you apply some throttle.

Can a carburetor be replaced in a TBI engine?

While it works fine for stock applications, the fact is that General Motors’ Throttle Body Injection (TBI) system is a nightmare for modified engines. Though it is possible to replace the injectors and throttle body, and to reprogram the computer, many find it simpler to “down-grade” to a carburetor setup.

What do you need to convert a TBI to a carburetor?

The most basic things you’ll need to convert from TBI to a carburetor is a carb and a matching manifold. You could try to track down a used stock manifold, but aftermarket aluminum manifolds like the Performer RPM make more power, are lighter and will only run you about $60.

Why does my 91 Chevy 1500 die at idle?

WORKING ON MY 91 CHEVY 1500 4BY4 . MY PROBLEM IS THE MOTOR DIES AT IDLE IT HAS THE 5.7 TBI. WHEN YOU LET THE MOTOR WARM UP IT WILL JUST DIE OUT AFTER ABOUT 5 MINUTES IDLE TIME BUT WILL START RIGHT BACK UP THEN DIE AGAIN MAYBE 2 MINUTES LATER. IF I PUT IT RIGHT IN DRIVE AND GO IT WILL RUN FIND UNTIL I HAVE TO STOP THEN IT WILL DIE OUT AGAIN.

Can a fuel pump be replaced with a TBI?

Of course, the simpler solution is to simply replace the fuel pump, which will serve the dual purposes of simplifying installation and replacing the worn fuel pump with a new unit. Though the swap is fairly straightforward, be forewarned that vehicles with the computer controlled 4L60-E automatic overdrive transmission will need additional work.

Is the Chevy TBI 454 having Idle problems?

Recently rebuilt the 454 in my 1990 TBI Burb. I am having a terrible time with getting it to idle smooth. The engine has a little over 500 miles on it. I have spent countless hours going over the engine looking for vacuum leaks and believe every thing is OK on that front.

Why is my GM fuel pump going bad?

In this tutorial I’m going to show you two different methods to verify if the no start condition on your 4.3L, 5.0L, or 5.7L throttle body fuel injection (TBI) GM vehicle is due to a lack of fuel, which usually means that the fuel pump has gone bad. One method involves using just starting fluid and the other involves using a fuel pressure gauge.

What kind of fuel pump did a 1990 Chevy k1500 have?

1990 chevy k1500 truck (5.0). Power at orange wire of fuel pump relay but pump won’t run. No power to any of the other 1990 chevy: Power at orange wire of fuel pump relay but pump wont run…

Is the fuel pump fuse no power on a 1990 Chevy?

Took a test light and found the fuel pump fuse has no power to it. Took my test … read more I have a 1990 chevy pick up trk 1500 , 5.7 engine.

What’s the idle speed on a 1990 Chevy?

Not open for further replies. I bought a 1990 Chevy 1500 pickup several months back. it idles around 1500 to 1800 rpm and it is tearing the transmission apart.

What causes stalling on a 1990 Chevy k1500?

So far it has a new distributor (for an unrelated problem), idle valve, throttle position sensor, knock sensor, temperature sensor, fuel filter, plugs & wires. The idle valve and tpi both tested bad, and replacing them helped on general driveability but didn’t affect the stalling.

When does the 1990 c1500 TBI idle go away?

1990 C1500 TBI 5.7L Idle is surging when warm. Unplug the MAP Sensor and the problem goes away, I replaced the MAP 1990 C1500 TBI 5.7L Idle is surging..MAP Sensor..goes away..Autozone… 1990 C1500 TBI 5.7L Idle… 1990 C1500 TBI 5.7L Idle is surging when warm.

What should the idle speed be on a GM TBI?

Insert a T-30 size Torx driver into the Idle adjustment screw that is located behind the plug removed earlier. Turn the screw to adjust the idle speed to 650 RPM +/- 50 RPM. Turn off the engine and disconnect the negative battery terminal from the battery using a wrench.

Why does my Chevy TBI idle like crap?

The engine is all stock except for the Edelbrock manifold. The truck idles like crap in park, but idles smooth in drive. It seems worse cold then after it warms up. I took it to get smogged (Ca) and it failed (high NO). The tech said it would pass easily with a new cat.

How does the GMC 5.7 liter TBI engine work?

Port the cylinder heads. This allows exhaust to escape the cylinders faster by removing metal from the engine where the exhaust manifold meets the cylinder heads. Exhaust gases can then move in a direct path to the exhaust manifold rather than having to bend around a corner to escape the cylinder.

What kind of intake manifold does a Chevy 5.7L have?

Intake Manifold, Performer Air-Gap, Dual Plane, Aluminum, Natural, Square/Spread Bore, Chevy, 5.0L, 5.7L, Each Need It Sooner? Speed Warrior™ Intake Manifold non/EGR 262ci-400ci, 1987 and later with cast iron cylinder Heads – non-Vortec, non-LT1

What kind of engine does a Chevy truck have?

These vehicles featured a 350 ci, 5.7 Small Block Chevy with TBI (throttle body injected) EFI system, and swirl port heads. Producing up to 210 hp in factory spec, this engine can also be retrofitted into an older car with a performance carburetor to produce up to 250 hp.

What was the year of the Chevy TBI throttle?

1987 1988 1989 CHEVY GMC TBI THROTTLE BODY TRUCK / SUBURBAN w/7.4L / 454c.i. V8. If you are not sure about your application please don’t hesitate to contact our sales/tech dept by emailing us and we will gladly help you.

What kind of car was the Chevy TBI in 1987?

Amazon.com: 1987 1988 1989 CHEVY GMC TBI THROTTLE BODY TRUCK / SUBURBAN w/7.4L / 454c.i. V8: Automotive

Where to spray starting fluid on GM TBI fuel system?

Spray starting fluid down the bore of the throttle body. When you have sprayed a good squirt of starting fluid, quickly place the air filter assembly’s cover back on. IMPORTANT: Placing the cover back on the air filter assembly is important because it’ll prevent any back-fire, that may occur, from spouting flames out of the throttle body.

What causes idle on a Great Lakes 4×4?

Take the egr valve out and see if there is a piece of carbon stuck in it. This would cause a rough idle. Also make sure the gasket is not leaking around the base of the egr valve. These would both cause the symptoms that you are experiencing.

Why does my truck idle when its cold?

When youre truck is just warming up, its still cold the efi is dumping fuel because its in like “Choke” mode. As it warms up, it leans the fuel air mix out to acomodate warm engine condition driving. So, when its idleing cold its got the fuel to compensate for the extra air leaking in.

Why does my fuel pump not prime with the key on?

Fuel pump doesn’t prime with key on. I’ve been trying to figure this out for a couple days now. My 01 Tiburon wouldn’t start the other day. It would crank, but wouldn’t fire. When I turn the key to the “on” position, the fuel pump doesn’t kick on.

What to do about a 1995 Chevy K 350 TBI?

Re: I have a 1995 chevy k 1500 350 tbi it hesitates when… Replace the distributor, $50. on line, the trigger coil wire is shorting out. The 50 bucks was well worth it. 10 mins truck ran great after that was done! You can’t post conmments that contain an email address. An expert who has achieved level 1.

What should the fuel pressure be on a 350 TBI?

From 370-440hp you need to bump the fuel pressure up on the 454 injectors to the 15-18psi to increase their flow rate to 100lb/hr.

What kind of engine is a Chevy TBI?

For more information go to https://www.p65warnings.ca.gov/ This Longblock engine includes block, crankshaft, connecting rods, pistons, timing set, oil pump, camshaft, lifters, bearings, gasket set, cylinder heads, valves and springs. The stress relieved block is completely CNC machined in our state of the art CNC machining center.

What was the year of the TBI fuel injection?

Vin code K – Used the TBI Fuel Injection 1987-1996. Used in various marine and industrial applications as well. Part # – 57P4068B $1700.00 Core Chare $350.00

What kind of diagnostic tool do I need for GM TBI?

The ALDL connector allows for full diagnostics of your unit. A scan tool can be used and set up for a GM TBI application to read the data, or to check for stored codes. Consult a service manual or see below for any check engine light code definitions. You can use a late 80’s or early 90’s GM TBI definition.

How to fix a 1990 Chevy 5.7L TBI fuel problem?