Scootertrash

OK, I'll try to keep this as brief as possible.
Truck was running rough. I checked fuel pressure and it would go up to 55+ psi but drop immediately. After some testing/checking I found that the fuel pump was leaking back into the tank. Changed the pump out. Also had some water in the tank, but the tank was completely emptied and the lines drained and filter replaced. Now I can't get it to start. When I started this project I drove the truck into the garage. Truck turns over fine. Here's the lowdown:

I have spark at all 8 cylinders

I have fuel spraying out of the spark plug holes on the compression stroke when I turn it over without the plugs in. If I put the plugs in and turn it over some of the plugs seem wetter than the others, some to the point of dumping fuel out of them. If I take a barbeque lighter to the spark plug holes (just tried a couple) I get a nice flame when the fuel burns out of the cylinder. (Scared the he** outta the wife when I did it. lol!) Plugs have been pulled and dryed after each attempt to start the truck

I unhooked the battery (mainly to clear the putor) and set the motor to cyl 1 at TDC and everything lined up under the cap. The only codes I had were related to the 2 downstream O2 sensors and a low voltage throttle position sensor code. TPS code was probably due to checking for leaks with sensor wires unhooked. Checked out the TPS and it checks fine.

I had a spare crank sensor and cam sensor in the cabinet, so I tried swapping them out, no change in symptoms. The sensors were old ones from a couple years ago when I had some issues and replaced them but it didn't fix the problem, so I saved them. Plugs are new. All connectors are connected.

7 of the 8 cylinders are at 150 +/- PSI for compression. Couldn't get the gauge into 8th cyl
(no 7). Motor is about a year old.

Tomorrow my plan is to remove the ignition module and have that checked and I was going to buy a noid to check the injector pulses, but if I have gas in the cylinders is that really going to tell me anything? I'm really at a loss here guys. I have spark and fuel, so WTH?? I'm pullin my hair out here and at 50 I don't have much to spare. I really need some suggestions here for stuff I may have missed. Can anyone help me out??
Thanks Guys!
Scooter

ukrkoz

well, let's do some logical thinking here.

to start, engine must have fuel, spark, compression and, of course, correct timing.
so, you have fuel, you have spark, question is - do you have the right timing?

btw, wet plugs won't start.

post what is that you are working on - year, engine, etc.

suzuki-guy

Sounds flooded and possibly your timing is off pull your plugs out and dry them off.

Scootertrash

Truck is a 97 K1500 4X4 w/ 5.7 liter

I put a timing light on # 1 cyl wire and when I turned the engine over the timing mark lined up. Just for kicks I put the light on #6 and the mark lined up like it is supposed to also. As stated above, I also set the engine to #1 TDC and the mark lined up and the rotor was in the proper place under the cap

Plugs have been removed, checked and dryed every time I tried to start it.

I am going to reverify the #1 TDC setting again in the morning, just to cover my rear. I haven't messed with anything related to mechanical timing and the truck ran when I put in in the garage. That is why it's so frustrating. I have spark, fuel ,compression, and the timing seems to be right.

Scootertrash

See my reply to the post above

89silverado283

i know this might be stupid but have you try to take the air filter off... "maybe" your not getting any AIR... no air no fire... just a thought... if that aint it then it might be your brain box.. we had an old 86 ford ranger that did this and it was the brain box... but i would keep to see if any air is getting in to the moter.. but please dont hold me to this i am only 19..

Scootertrash

89silverado: Yup it's gettin air. Air cleaner is off of the air duct.

Anyone know if I can put the computer from my wifes 99 Tahoe 4X4 5.7 in my truck as as to see if it's the computer and not screw up her computer by doing so?

treadhead

Just a thought, I am in no way a mechanic, but my soon to be father-in-law is, when I was having problems with my 89 5.7 he told me that if I ever have problems I cannot figure out, unplug the "brain" and plug it back in, sometimes they get,...confused for lack of a better word. he said unplugging it for 15 min or so will let it forget some of the parameters it was running. It will "relearn" them from a default setting when you get it started again.
Might not be the problem in your case but worth a look if you are thinking of swapping it for your wife's anyway.

Scootertrash

At this point I would prefer not to unhook the computer unless someone "in the know" tells me to. I have disconnected the battery for over 15 minutes. This should reset the computer, as far as I know. I also cleared the codes that were in the computer (the one I listed in my original post).

89silverado283

i just talked to my dad about the ford ranger we had and he said this is exactly what happenend to the ford... IF it was me i would find a brain box in the scrap yard YOU TRUST and go from there... but i really think its your brain box.. have some body hook a computer up to it and it should tell you if there is something wrong with it or not...