1990.. Been parked 2 yrs... No fuel to Tbi..Tia

[someotherguy]

They really need an education program for their counter guys, and most of it could be taught through CBTs. Complete enough CBTs and you get a raise! But then they'd have to pay for the raise, and they'd rather the customer just eat their fail for them.

It's one of those things that should be included in a little capsule along with a new module, much like a set of points used to come with some lube for the cam in the distributor. But that would cost too much..

Richard

 

[Schurkey]

It's one of those things that should be included in a little capsule along with a new module, much like a set of points used to come with some lube for the cam in the distributor. But that would cost too much.

I don't buy a lot of modules--and none recently. Whenever possible, I try to get them with the distributor attached, from the Treasure Yard.

Every module I have purchased new, came with a lil' capsule of schlubba intended as heat-transfer compound. Whether that was anything more than dielectric grease, I can't tell you. I used what came with the module, and I never thought twice about it.

I'm surprised that there's this much talk of heat-transfer compound under the module. It never occurred to me that folks would fail to install "something" under the module.

Most auto parts stores around here have a counter-display of "one-use" automotive chemicals--module compound, anti-seize, brake caliper grease--all sealed in a little foil packet as if they were Alka-Seltzer.

 

[someotherguy]

I'm surprised that there's this much talk of heat-transfer compound under the module. It never occurred to me that folks would fail to install "something" under the module.

Most auto parts stores around here have a counter-display of "one-use" automotive chemicals--module compound, anti-seize, brake caliper grease--all sealed in a little foil packet as if they were Alka-Seltzer.

Yeah, but if the counter jockeys are recommending the wrong product.. not good.

Richard

 

[Casey604]

T.i.a....
ANY IDEAS..
I'm lookin atta 90 2d swb 4wd 97,00 originalmiles... it was parked by the owner 25 months ago with passenger rear brake issue..
Turns over.. will fire with a starter fluid... see no gas pumped at tbi..this...an hear Fuel pump come on and prime.. Thanks again in advance...

Your 100% that the fuel pump is primeing?? And the injectors are not spraying during cranking? If you see no fuel, feel around by the oil pressure sensor wires and see if you get spurts of fuel while someone is cranking. Could be messed up connecter, or the oil pressure sensor got busted, I know it sounds odd, but I've had it happen.

 

[lumpdog602]

When all basic methods fail, and you finally admit to yourself you need to run a fuel pressure check as mentioned earlier - don't be surprised when you discover zero pressure, and pull the sender only to find the hose from the pump to the sending unit has deteriorated into goo from sitting immersed in bad fuel.

Richard

Yes sir to this^^^^. Fuel pump is pumping, pick up is picking up, fuel can't leave the tank due to 32 year old 3" section of rubber hose being all crusted out. Exactly what happened on my 93 stepside. Off came the bed to R&R the fuel pump. Problem solved.

 

[Vettepilot]

Just my own troubleshooting opinion here guys:

Must have tools = fuel pressure gauge and Noids. In this age, these should be as necessary in a tool box as a screwdriver and pliers.

Get a length of garden hose or similar, and stick it in the gas filler. Stick the other end in your ear and have someone turn the key to "on". You should clearly hear the fuel pump run for a few seconds and stop. If you hear it, continue.

Then, next since it's easy, plug the NOIDS into your injector pigtails, and crank the engine and see if they flash. If not, trouble shoot that. You rarely find the problem here on an unmolested vehicle. No non-professional wants to pay for the Noids, but you can make some up for nearly nothing. (Google DIY Noids)

The next thing to check is fuel pressure. This is a hassle with TBI, but you have to do it. Either buy the fitting and hassle with the install, or you could just cut the supply line and "T" in a test connection since it's an under 15 pound pressure system. (FIRE danger if ya screw up here!) Get it all hooked up with your gauge, and again, have someone turn on the key while you watch the gauge. Do this several times, waiting about one minute between on/off cycles of the key. You want to see about 9 to 12 lbs. of pressure on a stock system. As much as maybe 18 on a hot rodded system. [THIS IS THE MOST DIFFICULT PART OF TROUBLE SHOOTING THE TBI SYSTEM--> BUT THE MOST IMPORTANT!!] (Just leave the fitting in place, and it will be super easy next time!)

I really hope you didn't go after all this without really verifying there's actually fuel in the tank, right?? (Not just by the fuel gauge--> GM fuel gauges often fail by going to "Full".)

Now, based on the outcome of these tests, you have an idea of in which area/system the fault lies. Then you can either chase that, or when you ask for help, you have vital troubleshooting info to work with.

In this case, and with today's totally rotten fuel, it is most likely stuck injectors as long as the rats haven't eaten any wires or hoses. I just had a TBI system stick it's injectors here after only sitting unused for 3 months. (120 degree plus temps here, so the fuel only lasts about five minutes.)

This procedure is not super quick nor free, but is how the pros do it, and will save you HOURS of chasing your tail, guessing, and save tons of frustration and possible incorrect parts replacement.

Note: The BFH to the injector pods, while mentally quite therapeutic, can do damage!

Vettepilot

 

[Vettepilot]

Additional tip. If all above points to stuck injectors, try this. Remove the injector connectors, and touch the terminals of a 9 volt battery quickly on and off to the injector terminals. Do this when it is totally quiet, and listen very carefully. If the injectors are not stuck, you should hear them "click". Just make and break the connection quickly and repeatedly while listening so as to not overheat/damage the injector.

No wiring necessary. The 9v battery terminals will match up enough to the injector terminals to make the quick connection necessary. If you hear the injectors "click" they are likely fine, though their filter micro screens could still be clogged...

Vettepilot

 

[masher41]

When all basic methods fail, and you finally admit to yourself you need to run a fuel pressure check as mentioned earlier - don't be surprised when you discover zero pressure, and pull the sender only to find the hose from the pump to the sending unit has deteriorated into goo from sitting immersed in bad fuel.

Richard

Exactly what happened with my truck after sitting for 1 1/2yrs w/ bad fuel.

 

[Treysanatomy1]

Your 100% that the fuel pump is primeing?? And the injectors are not spraying during cranking? If you see no fuel, feel around by the oil pressure sensor wires and see if you get spurts of fuel while someone is cranking. Could be messed up connecter, or the oil pressure sensor got busted, I know it sounds odd, but I've had it happen.

Yes I'm sure... Thnks.ill check..

 

[haroldwca]

Well, I found my way all the way to page three, and I was about to suggest what Vettepilot suggested. This is the EASY was to check throttle body injectors on this truck. I went through a similar scenario with my 1988 SBSC 4WD. Sat for 10 years before I brought it back to life. Try the 9V battery. It will save you a lot of time.