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Truck wont start - ideas?

Seeing as the coil was probably never replaced on this thing, I’ll probably do :
- coil
- spark plugs/wires
- distributor rotor and cap
- oil change

Slow down! You have a fire extinguisher ready, ya? Figure out the existing problem before installing any more new shit. You said the truck ran fine before you replaced fuel pump, fuel injectors, fuel filter, blower motor, fan relay, starter motor. Did you fire it up inbetween any of this, or all done at once?
 
Slow down! You have a fire extinguisher ready, ya? Figure out the existing problem before installing any more new shit. You said the truck ran fine before you replaced fuel pump, fuel injectors, fuel filter, blower motor, fan relay, starter motor. Did you fire it up inbetween any of this, or all done at once?
I don’t, but I’m thinking I should get one now… think it’ll blow fire if I try to crank?
I didn’t fire it up between any of that, did it all at once
The only thing I’d be buying is the coil. I have everything else as I was already planning on replacing
 
In the 1st post list I do not see fuel pump.

When you replaced the starter, did the fuseable links get reinstalled, were they damaged ? Might be that you don't have power to some circuits.

I still don't like the amount of fuel that I see in that picture. Should never have gas dripping from anywhere let alone an exhaust pipe.

Every time you turn the key from off to run, the ECM signals the injectors to spray 2 seconds, then waits for oil pressure signal from sensor to turn the fuel pump on. It seem you 2 second prime is working.
need to figure out why there is so much fuel in the cylinders. If you put your new plugs in before the fuel issue is fixed, you may foul them out too.
recheck your injector install and gaskets. Are the injectors new, manufactured, or used ? What brand ?
 
So now we need to know if the fuel pump is correct pressure. Over pressure could overwhelm the injectors.
 
So now we need to know if the fuel pump is correct pressure. Over pressure could overwhelm the injectors.

Not if the regulator is working properly. You can run the 80(?) PSI EP381 without issue on these setups, stock.

It sounds (and looks) to me like there is way too much fuel, from something. As stated above, you should never see fuel, anywhere. It's a fire waiting to happen, and it's absolutely, 100%, abnormal.

If ANYTHING at this point, I would try to get someone to help. Stop worrying about all the what-ifs, and make sure this thing isn't going to burn down if you get spark. I would have someone turn the key to run (from off) while I leaned over the throttle body unit and looked for EXTERNAL leaks, such as where the fuel lines attach to the throttle body. Then I'd crawl under the truck, and I'd have my helper repeat that test, making sure there was no fuel running down the back of the engine off the fuel lines.

Only THEN would I worry about anything else being an issue. Again, already mentioned, key off to run will run the fuel pump for just a few seconds. Not nearly enough time to pump a bunch of fuel anywhere at 13PSI. But if there is a leak, you will see it.

I wouldn't worry about anything else at this point, except a fire. And fuel outside of the TBI is what will cause that. You need to figure out why there IS fuel outside of the TBI. If it's a leak, stop, do not pass go, fix it. Period the end.
 
Read through this thread


I changed injectors and messed up and didn't put the little owl eye rubber things on and it made similar thud as you describe
 
Condensed version:
1. operator error not putting the rubber owl eye things on the injectors, caused an electrical issue.

2. Pretty sure it blew the pickup coil in the dizzy and the computer which stopped fuel pump and spark in my case, aftermarket frame mounted fuel pump.

3. New dizzy and new computer solved problem and I located many other issues along the way.

summary: don't forget the little owl eye things, it will cost you money.
 
woah, tons of information here. thanks all

1- little rubber injector boot things were replaced and replaced correctly. ive doing injectors before and almost forgot them the first time
2- i did notice the gasket underneath the throttle body spacer that connects to the air filter housing was cracked off. this would make sense as to why there is fuel on top of the block by the throttle body
3- fuel pump was never touched, fuel filter was replaced. and in the right orientation

ill have to read through the above stuff later
 
In the 1st post list I do not see fuel pump.

When you replaced the starter, did the fuseable links get reinstalled, were they damaged ? Might be that you don't have power to some circuits.

I still don't like the amount of fuel that I see in that picture. Should never have gas dripping from anywhere let alone an exhaust pipe.

Every time you turn the key from off to run, the ECM signals the injectors to spray 2 seconds, then waits for oil pressure signal from sensor to turn the fuel pump on. It seem you 2 second prime is working.
need to figure out why there is so much fuel in the cylinders. If you put your new plugs in before the fuel issue is fixed, you may foul them out too.
recheck your injector install and gaskets. Are the injectors new, manufactured, or used ? What brand ?
i know that the fusible links were replaced, but i didnt think to check it when i replaced the starter
the fuel injectors were new - Brand=standard
the fuel pump wasnt touched at all, just the fuel filter
sounds like at this point not, check :
- fuel lines at throttle body
- coil?
 
Condensed version:
1. operator error not putting the rubber owl eye things on the injectors, caused an electrical issue.

2. Pretty sure it blew the pickup coil in the dizzy and the computer which stopped fuel pump and spark in my case, aftermarket frame mounted fuel pump.

3. New dizzy and new computer solved problem and I located many other issues along the way.

summary: don't forget the little owl eye things, it will cost you money.
dizzy = distributor cap right? lol

just read through the thread you sent.
it gives me hope that if i replace the plugs, wires, dist. cap/rotor, coil that i have then i might be onto something.
only extra items you did were ignition module, ignition switch in dash, and computer under dash.

im not the greatest at diagnosing these things, but i know how to wrench some new stuff in
 
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dizzy = distributor cap right? lol

just read through the thread you sent.
it gives me hope that if i replace the plugs, wires, dist. cap/rotor, coil that i have then i might be onto something.
only extra items you did were ignition module, ignition switch in dash, and computer under dash.

im not the greatest at diagnosing these things, but i know how to wrench some new stuff in
Best advice I can give you:

Do one thing at a time
 
soooo i just speed readthrough all 3 pages. i saw all the posts about hydro locking with fuel... can that really happen with factory tbi??

i saw the photo of the fluid coming out of the exhaust collector- was that confirmed to be fuel????

reason i ask- how i came to own my 1989 suburban:

previous owner bought on ebay. over 6 months he noticed every once in a while it wouldnt start. sometimes after several attempts it would start cranking and run. He put a new battery and alternator in it... then one day it just wouldn't crank. towed to his mechanic. mechanic said you need a new started and positive cable going to the battery... truck wouldn't start. mechanic ("mechanic") siad he thought the 700r4 was locked up and needed to be rebuilt. That was the last straw, and the owner sold the whole truck to me for 500 bucks. I towed it home, pulled the spark pugs out, engine cranked over like a pissed animal.... aaaaaand it shot rusty water out of one of the spark plug holes and made a big mess.

It had a blown headgasket. gasket was blown in just the right place to allow a pathway to the coolant. im sure if the truck had continued to drive, other things like overheating and blown radiators would have happened, but, it never got that far. When the engine was shut off with the piston down and the engine hot, the residual heat/pressure in the cooling system pumped the cylinder full of water. the first few times were just a little bit of water and somehow the engine eventually worked it passed the rings enough to open a valve and let the water out. that last time locked the motor up solid. I had the truck running great 2 weeks later after having both heads rebuilt.
 
soooo i just speed readthrough all 3 pages. i saw all the posts about hydro locking with fuel... can that really happen with factory tbi??

i saw the photo of the fluid coming out of the exhaust collector- was that confirmed to be fuel????

reason i ask- how i came to own my 1989 suburban:

previous owner bought on ebay. over 6 months he noticed every once in a while it wouldnt start. sometimes after several attempts it would start cranking and run. He put a new battery and alternator in it... then one day it just wouldn't crank. towed to his mechanic. mechanic said you need a new started and positive cable going to the battery... truck wouldn't start. mechanic ("mechanic") siad he thought the 700r4 was locked up and needed to be rebuilt. That was the last straw, and the owner sold the whole truck to me for 500 bucks. I towed it home, pulled the spark pugs out, engine cranked over like a pissed animal.... aaaaaand it shot rusty water out of one of the spark plug holes and made a big mess.

It had a blown headgasket. gasket was blown in just the right place to allow a pathway to the coolant. im sure if the truck had continued to drive, other things like overheating and blown radiators would have happened, but, it never got that far. When the engine was shut off with the piston down and the engine hot, the residual heat/pressure in the cooling system pumped the cylinder full of water. the first few times were just a little bit of water and somehow the engine eventually worked it passed the rings enough to open a valve and let the water out. that last time locked the motor up solid. I had the truck running great 2 weeks later after having both heads rebuilt.
Sheesh what a story! Haha, sounds like a good deal.

I thought the same thing about heads being the ultimate problem. But I touched and smelled the liquid out of the exhaust, and it definitely smelled like gas.
When you pulled the spark plugs out, you cranked with no plugs or wires? Debating trying that or just replacing the plugs/wires and all
 
Since the injectors were replaced and there’s extra fuel in the motor right after that, it seems that’s a likely source of the problem. Put the old injectors back in and get the motor running.

Then mess with injectors if they need it, but they probably didn’t need to be replaced.
 
Since the injectors were replaced and there’s extra fuel in the motor right after that, it seems that’s a likely source of the problem. Put the old injectors back in and get the motor running.

Then mess with injectors if they need it, but they probably didn’t need to be replaced.
My dumbass threw them away ‍♀️ Wonder if I need another set haha
 
My dumbass threw them away ‍♀️ Wonder if I need another set haha
Have you tested the new ones with a timing light? There should be strong spray when they activate. If you see dribbling or gas pouring down, something’s wrong. I’d be willing to bet you have a gasket or something loose up there.

Get the old ones out of the trash if you can.
 
Thanks to some of the advice I received here after I realized I had forgotten the owl eye isolator things, I started looking for spark on mine, which what finally led me to the computer and distributor. A little work with the voltmeter and test light helped alot. You can also test the injectors, I took them out and tested.
 
Just because parts are brand new doesn't mean they're good. You can ruin all your troubleshooting on that assumption. Our world is full of junk parts these days.
 

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