Well, I don't know where to turn on this one guys. My Z was running just fine until i decided to play with the fuel pressure the other day.

I did a plug change also and went from 46 to 50 psi and now the car wont even start. Let me give you some background info. A while back (like over a month) ago i was at the track and was spraying approx 150 shot. The car ran like crap...HUGE backfires, etc etc. I got back to the pits (car ran fine/strong on motor) and DID NOT check the plugs like I should have b/c I am a complete a-hole!! Anyway, fast forawrd 1 month. Car ran great the whole time up until yesterday when I decided to change the plugs (6 out of 8 were blown to heck and the tips were all busted off, etc) Well, thats a damn shame and hopefully all that got spent out of the exhaust and not stuck in a piston

So, here is how i diagnosed the sitution. (Mind you I am a GM /ASE certified technician and have been wrenching for years and know f-bodies inside and out LOLOL)

SPARK:

1. Check and re-check and RE-CHECK spark plug wires for propper positioning. ...OK, but no start
2. Pull dist. cap and check cap/rotor...OK, but no start.
3. Pull a few random plug wires and check for spark...Ok, but no start
4. Pull same plugs and attach to wires and check for spark...OK, no start
5. Pull cap and rotor AGAIN and replace amplifier module (it is 10 yrs old anyway, and i wanted to throw my MSD piece on regardless....OK, no start
6. Pull #1 plug, get TDC and check rotor position, check mark on balancer and check to see if it lined up at 0...all OK, no start
7. check coil...good, no start

Conclusion: it has spark and timing is good!!!!!!!!!

Fuel: OK, so in my FP tinkering I went WAAAAAAAAYYYYYYYYYY overboard on accident and bumped it up to like 80 psi once. No big deal *I THINK* b/c i didn't start the car or anything. I was just checking by "ignition on" and letting the pump prime, but not attempting to bump it over at thast point. So I say holy S%$^ and turn the key back and re-adjust...got it to 50psi eventually LOL.

Fuel diagnosis:
1.Check FP at shcrader valve....got 50 psi..OK, no start.
2. So it cant be a fuel filter or kink in any lines or anything "BEHIND" the shcrader valve.
3. Whip out electrodes and plug into injector harnesses...like 6 of them (2 of them are a beeeatch)....bump car over and watch the lights. All are flashing properly, etc...OK, no start
4. I have an extra MAP sensor, so i swapped that out...no start.
5. All vaccumm lines are where they need to be, etc etc etc

My question is>> could I have seized up the injectors by nailing them with all that fuel pressure?????? Can that happen?? I never heard of it in this manner before.

I hardly think so but im lost right now guys????????

I tried spraying some starter fluid in a couple cylinders and TB, etc...nothing

I checked the computer, pulled it down, switched chips, scanned for codes...nothing


the motor spins but it wont fire!

whats the deal here???

 

Check compression and check for exhaust restriction.

Should be able to rule out fuel issue, since spraying into the intake with fluid and still no start.

As long as the spprak is occurring at the correct time and you have spark, can rule out igition.

Only leaves compression of the mixture, and ability to get it out.

 

did you get this problem solved yet?

 

i have seen a FI car get flooded with fuel.... try draining the fuel rail and then try starting the car when you do Try starting ti like you would when its a Carbed motor

 

well, pulling most of the plugs and cranking the motor was my "un-flood" it method of choice.

Anyway, the problem was solved. Thank you for the suggestions, comments, etc.

Every time I'd set the car up and get ready to start it, I would go to the garage sink and wash up real quick in order to not trash the interior, etc

Well, my a-hole neighbor/on-looker thought in his un-sober state of mind, that it would be funny to play musical spark plug wires and he swapped all the wires over a space or 2 on the distributor. Yes, he did it to me AT LEAST 3 times (can't remember how many times i checked 'em anymore) From where the sink is you cant see out of my garage.

Anyway, he thought he'd be "nice" and tell me what the heck was going on..... 1.5 FRIGGIN DAYS LATER!!!!!!!!!!!!!

He still thought it was hilarious and I was/am pissed BIG TIME. Well, i wont say what i did to him, but it scared him 1/2 way to death. Definetly took a few years off his tab.....A-HOLE!!!!!!!!!!

thanks again guys.....no more "Watching and learning" for his butt

 

HAHAHAHAHA

so what did you do to him???

 

well, ill just make a comment and not directly answer your question 86.

"I am an avid assault rifle collector/shooter."

'nuff said

 

*dsiclaimer*...no rounds were fired LMAO

 

Glad to hear you got that solved. Nothing like having a buddy help you work on your ride.lol. You might have even had Vader scratching his head on that one.

 

NEVER do a job half way. I would have taken his joke out on his hide. You NEVER mess with a man's ride without dire results.

 

Morley, man trust me, I feels/felt the same way, but to see the look of despair on his face was good enough for his FIRST AND ONLY warning. Anyway, check this out now: (this happened after the whole musical spark plug wire incident and the car was runing/idling nicely up to this point )

had my car running pretty good for a while now until just recently. Today, i noticed the car had a hard time starting. it took a while longer then ususal to fire, but still no big deal. However, the idle would jump up to like 2500 for approx 10 seconds then come back down to normal and run fine. it only did it on start=ups (hot or cold).

Well, on my way out tonight, it did it again except it jumped to 4K+ rpm and STAYED there....no matter what i did, it wouldnt come down AT ALL!

TPS is set at .57 and i replaced the IAC right there in the parking lot. I checked all the general vaccum hoses and lines I could think of. Under TB, FP regulator, EGR, etc but nothing was wrong.

What the heck is the problem here!?!?! I'm so damn sick of the trouble this thing has been giving me. Between tuning and all that stuff, its getting old QUICK