no start [confusing]

I have a 1988 chevy k1500. It all started with black smoke and stalling, and now I have no gas coming out of the injectors even though I have fuel pressure at the TBI. I've also noticed that I have no check engine light coming on when I turn the ignition to on. After setting the rotor in the correct position the truck started however as soon as I pushed the gas pedal the truck died. At least the black smoke was gone. Previously, I cleaned the carberator, changed the MAP sensor, temp sensor, the only o2 sensor, ignition module, computer, and battery cables. In another post I read that the ignition module was causing another gentleman the same problem. Just confused on this one. The last time I changed the computer the check engine light came back on.

Have you pulled any codes out of the computer? Have you checked the resistance of the distributor pickup coil that connects to the ignition module? Fuel filter replaced? Good grounds on the motor AND from the battery to the vehicle frame? So many people replace their cables or battery and forget that the frame needs to be connected to ground just as much as the engine block. Good luck. -Chris

Can't get to the codes the MIL doesn't come on .. period. I tested the spark today, and it seems fine. When I dumped some gas into the TBI it started right up. I also checked voltage going to the fuel pump today, and it is definitely fine.

Get the mil light to work first or you'll be shooting blindly. Where did you check the voltage at for the pump? Can you take a can of Gumout and keep the engine running by spraying it into the throttle body? Have you tested your injectors or used a "noid" light to check that the computer is actually firing them? So many possibilities.

Yeah I checked some more things out. I actually pulled the tank down to check for shorts and stuff. I tested the fuel pump by giving it power directly from the battery and it works. There are three wires going to the battery and I'm testing it at the connector for the fuel assembly/fuel pump on top of the tank and there is an always hot wire that is getting power. Some kind of weird electrical problem, the fuel pump isn't starting when you start the truck. Still can't get that MIL light to come on.

BTW, yeah it does work when you pour gas in the TBI. Computer is well grounded, engine is well grounded, I checked the resistance of the pick-up coil earlier and it was fine (i will check it again though), power to the computer is good, tan/white wire to computer from fuel pump relay is good, relay is getting power, gets spark, continuity between map sensor, distributor, and many of the wires is fine.

I did notice that the white wire (ignition control) that I think is going to the computer from the back of the distributor (think it comes from the spark control module) had many black spots. Don't know if this is heating up and losing continuity. When it is cold the continuity is fine.

Do u know how to test the fuel pump relay? I'm going to test some more things tomorrow.

I had the very same problem myself, took a week to figure it out. If you have no fuel, and no fire then your ignition switch is out. When you turn your key, and you get no gage lights, then the circuit is not turning on. Try you ignition switch, should fix the prob.

1997 c1500 5.0 ext. cab

I had almost the same problem on my truck. Randomly one day it wouldn't start. I also noticed that the fuel pump wasn't making its characteristic 'whining' sound when I turned ignition on. Replaced fuel pump relay. Nothing. Checked fuses and found that ECM fuse was blown. When I tried to put a new one in to replace it would blow instantly. Obviously there was a short and I checked only to find that the hot wire from the battery going back to power the fuel pump had melted to the hot exhaust manifold and was shorting, not allowing my fuel to get to the injectors and causing the ECM fuse to blow. Problem fixed by getting cable away from hot parts and wrapping with electrical tape. Truck started right up and no problems since.

Hey I actually figured this one out. I noticed that the computer and the fuel relay were not getting ground when the key was turned. So I ended up running a second ground to each. Now I have my check engine light on when I crank it, and the fuel is being sprayed into the TBI. It runs awesome now that I set the time. Just awesome!!! It feels great to know that I practically built the entire truck after parts started breaking left and right.

[QUOTE=prong2002]Hey I actually figured this one out. I noticed that the computer and the fuel relay were not getting ground when the key was turned. So I ended up running a second ground to each. Now I have my check engine light on when I crank it, and the fuel is being sprayed into the TBI. It runs awesome now that I set the time. Just awesome!!! It feels great to know that I practically built the entire truck after parts started breaking left and right.[/QUOTE
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Hi, I had the similar problem on my wife's car a 91 seville and I replace a number of parts even the distributor when the dealer said it was the culprit.
Nothing helped until I used my battery jumper cables from the engine block to the battery negative post and from the battery negative post to the body.
This fixed the really bad running so I cleaned the wire terminals on the ground bolts, and added a ground wire from the body to the block,
On that car and probably our trucks there is/are ground bolts near the battery where a lot of the circuits go to ground. Computer, sensors etc.
Severl others on a Cadillac forum hav also fixed some really bad problems by fixing/cleaning the grounds.
Her car is interesting in that you can run all diagnostics from the on board computer. Even watch the O2 sensors while running.
I think except in my case it is a wasted feature because most Caddy owners won't do it or even care. Thr owners manual doesn't even tell you about it.(I learned it from the shop manual) They just go to the dealer.
This feature should have been put on cars like chevys.
Bob B

I feel all of your pain! I have an Audi that went through a similar condition. I didn't have the time to do the tranny swap myself, so took it to a certified Audi dealer (boy was that a mistake) where they ordered the tranny (that is essentially the same model for all Audis from 84-94 or so) with exception to the need for a ground wire bolted to the tranny/motor on some off models. In summary, I was charged for the new starter that wouldn't turn, hours of troubleshooting as to why the car wouldn't even turn over... and had it towed home with a nice $1200 bill on top of the $2500 for the tranny installation. All said and done, I clamped a jumper cable from the battery ground to the bellhousing and the car started right up!