After tearing down my 89 TPI to change out the heads and intake I have a no start condition that has perplexed me. Everything went smoothly on reassembly but now I cannot get it to start.
It sounds normal turning it over but will only sputter. I hooked up my scanner and all of the readings appear to be normal. After turning it over and listening to it sputter, I realize it is rythmic and decide to do a hand test on the exhaust headers. What I discover is that I only have heat in #7, all of the rest are stone cold. So I check 2 other random cylinders for compression, spark, and injector pulse. All of these things are present. I disconnect my digi MSD thinking it may have failed on me but the condition still persists even after it is taken out of the loop. I have fuel pressure. I Check the distributor timing and firing order without finding a problem. So what I have is one cylinder trying to run, and 7 that are dead even though they seem to have compression, spark, and fuel. Any suggestions?
Thanks
Roy

 

Remove the dist cap & #1 spark plug and manually turn the engine till you feel compression pressure at the #1 plug hole.

I assume you know there is fuel pressure at the rail.

At that point the damper mark should line up with the timing pointer and the dist rotor should point to #1 plug wire terminal.

If timing is ok & fuel pressure is ok, use a test bulb or DMM to see if the injectors are firing.

If ok there do a compression check.

 

65Z01,
I have already done all of that.
Thanks,
Roy

 

All the plug wires are in the right order too, right? I'm guessing that's what you mean by firing order.

Just figured I'd throw it out there...

 

Larry,
Yes that is what I meant.
It has to be something either completely off the wall or so simple I cant see it. I really cant figure out what would cause only one cylinder to run and the rest to be dead.
And I drove it into the garage, it was running fine before I tore it down.
Thanks,
Roy

 

This has got to be some kind of ignition issue. I just pulled off the MAF and sprayed starting fluid directly into the plenum. Put it back together and it still ran on only #7. I figure if it was fuel I would surely get a spurt of running on all 8 until the ether ran out. But nope, all cold except #7.
Roy

 

just had the same problem ohm the injectors, they should be around 16.5 ohms +/- 1.0 ohm!!! between any two injectors. i had one injector at 2.2 ohms and it kept the engine from running. disconnect all the injector wires and ohm injectors if you find any bad ones, go ahead and hook up the good ones and it should start

 

Vetteman,
Thanks for that suggestion, I thought you might be on to something as these are not the same injectors I took out of the car. So even though they were running fine in the other car I figured this was a possibility. They all OHM out between 16.3 and 16.5 though so I guess it is back to the drawing board.
Roy

 

Are you 100% confident in your preload of lifters ??
Did you actually do a compression test on all cylinders ??

 

I'm betting on one or the other! either your valve lash is off, which I would all most bet on, or your timing is way off........

 

Agent, I am pretty sure of my lifter preload. I did not check compression on all the cylinders, I picked one on each bank, and they both pumped right up to 180 lbs on 3 rotations, even without opening the throttle plates. Neither of those two cylinders I did check are attempting to run though. I do appreciate the suggestion however. I am looking at an idea from a real sharp chev tech that I know, if it doesnt pan out I am going to have to go back over some of the ground I have already traveled and that will be one of the things.
Thanks,
Roy

 

I just put new heads on my L98 and I bet your valves arent adjusted right. Since its not starting they're probably too tight. Its very touchy on these cars.

 

You hit the nail on the head,or rather AGENT86 did, you need to re-adjust lifters,and that's why you're experienceing your problem! you did it all wrong! you can't just pick 1 on each bank after removing/installing heads. pretty easy, but time consuming.

 

Rick, I think you misunderstood my post. I am not saying I adjusted one on each bank, I am saying after I had the problem I checked compression on one on each bank to make sure I didnt have the valves too tight, and those two cylinders both had 180 lbs of compression. I adjusted the valves the same way I have done dozens of times, and I have them set at one turn from zero lash. Its certainly not hard to pull the covers and back them off a bit, I can give it a go but I dont think thats going to fix it. If I had a compression issue on either of the cylinders I checked that would have certainly been an easy point to the problem and an easy enough fix.
Roy

 

Ok I took your guys advice, pulled the valve covers and took 1/3 of a turn of preload off of all the lifters. I then verified a few of them to determine that this did place them at about 2/3 of a turn of preload like it should have if my work was correct the first time when I set them at 1 turn and indeed I did confirm this.
Unfortunately this has made absolutely no difference in the no start condition. No 7 tries to run, all of the others are stone cold.
Roy

 

10 cents says it's something simple. Maybe a fresh start to dizzy timing, firing order and lifter preload will correct this. Iv'e seen a lot of posts where they swear they have it right and it turns out they had the dizzy out 180* or the firing order out of whack or something simple.

 

Agent, I will take that bet and I will happily send you the 10 cents if you are right! But I am sending you my address to collect if you are wrong!
I do appreciate you guys trying to help and I agree that a lot of times a poster will have a simple problem they just cant see. So I dont want this to come across the wrong way, but I am not new at this. I have been building and rodding small blocks since I was 16, I am pushing 50 now, and if this was a mechanical issue as simple as the firing order, dist position or lifter preload I would have found it in the first 5 minutes after I had the problem. Plus the only one of those things that can explain to me the way it is acting would be the lifter preload, and I have now triple checked that. It has no backfiring or strange cranking, and no matter what I have done with the distributor (including moving it 1 notch once just to get more adjustment) it always runs on #7 and only #7. Coming from the old school, I admit to being not quite as sharp on the electronics as the mechanics which is where I need the help.
One possibility I am thinking is that I disturbed a wire in the harness while manipulating them around and even though I have an injector pulse the ground is weak, so it can only pull open the first injector in the harness which is #7. Does this make any sense? If so does anybody know which ground traces specifically back that could cause this?
Also could this be a VATS issue somehow? The first time I go out to crank it after it sits a while it almost sounds like it runs for a millisecond and then goes back to just #7.
Wild *** guesses welcome at this point
Thanks everyone
Roy

PS: Are we betting 10 american cents or 10 canadian cents??

 

You can rule out VATS as that would give you a no crank situation. You can test your weak ground theory by switching #5 and #7 injector connectors. I don't know if you have a FSM, so I will link you to info from mine(86).
Good Luck
http://members.shaw.ca/corvette86/En...ButWontRun.pdf
http://members.shaw.ca/corvette86/En...agram%2086.pdf
http://members.shaw.ca/corvette86/Fu...mDiagnosis.pdf
http://members.shaw.ca/corvette86/Ig...System-EST.pdf
Oh, American dimes only

 

I'm sorry Roy, I did read that wrong. So, it sounds like you've double checked your work. And it sounds like you've eliminated fuel as a problem.So, assuming we have fuel and compression, both of which you have eliminated that leaves us with valve lash and ignition....and you've more than likely eliminated the valve lash....that leaves us with ignition......like you I've been turning wrenches from 15 to now 63, can't tell you how many times I've sworn I had double checked my work just to find out my bone head had messed up on the timing issue.
If you've confirmed you have spark to each plug? To me, that only brings us back to putting them all togeter at the right time! I certainly don't mean to insult you or challenge your abilities, but IF it were me, I'd pull #1, make sure it's TDC on the compression stroke and take one more look at where that rotor is pointing. And if you're 1000% correct...I'd say it's time for a new coil!

 

It's not the coil. If the coil were bad, there would be no spark, even at the wrong time.Other than that, based on all the symptoms reported, the only guess I have is the firing order. It is the one thing that has messed me up more times, when I knew that I knew better. After you look at a mistake for so long, it begins to looks right. Have a wife, or buddy check the firing order. They don't have to know squat about cars, you can direct them, but have them CAREFULLY track each wire. We're pretty sure it has fuel, there is compression on at least two cylinders, and the plugs each spark. Because the lifter preload has been triple checked and there is compression, timing and more specifically the firing order is my best guess. I'll put my American dime on that one. Good luck, and...

RACE ON!!!