I have a 91 z28 350 tpi 5 speed. The car died on the road. Hasn't started since. The motor turns over but there is no spark, no codes, Injectors working, Fuel pressure good, New chip with Vats Provision disabled. Good power throughout the car. Starter is new and strong.

New parts installed:

1. Ing Module.

2. New Memcal

3. New Coil

Checked for bad pickup coil ( seems fine ).

Checked Injector resistance ( good )

Checked Ingnition switch ( working )

Checked for bad grounds ( lots of them but not sure which ones most are in harness!! )

I'm running out of ideas. Please help!

 

rotor, cap, wires might be something to look into

 

You say, "Good power throughout the car." Have you verified voltage at the ignition?

Bad reluctor (trigger wheel) would be another possibility. Not sure how you would go about testing that to verify other than replacing it, but there have been reports of them going bad.

No spark conditions rarely set a trouble code. The ECM just doesn't monitor that part of the ignition system very well.

 

You checked the pickup coil, so what was the winding resistance? Was it over 500 ohms? Any resistance reading to ground?

Try disconnecting the TACH lead, just in case the tach filter has gone belly-up.

And just to verify, you are getting 12VDC at the BAT terminal on the coil when you turn on the ignition, correct?

 

Check the fusible links.

 

Ok all! here is what is happening. I tested the car again today. SERVICE ENGINE SOON LIGHT stays on WHEN KEY IS TURNED ON! I get spark through the coil for about 2 seconds then shuts down.. Wait about 2-4 minutes and it does it all over again. I got a new chip with vats disabled which is supposed to knock the whole vats system correct?

(EDE) Cap and rotor I will change next. But still looks good.

( PASKY) Fuseable links I will also check But I think they are fine.

(FIVE7KID) I would like to know what a reluctor is. Is it in the distributor? Never heard that teminology before.

(VADER) I checked standing resistance only. About 700 ohms + Through the 2 wire conector. Nothing on testing to ground. I didn't have anyone to turn the car over for me. I will do the tack lead test and check for 12v at coil.
But it does see voltage.

I will Do all these tests and fine out. Anything else please let me know.

 

I would give the Ignition Control Module under the cap a lil tap. Three of our vehicles do what your are talking about. I tested all that junk, took it to the dealer, and they still couldnt find anything wrong. The Module is under the cap if you have the external coil... I know it sounds medival but it works for me...lol My S10 Blazer does that all the time, I just pop the hood and tap the module and go on my merry way.... Just a thought to try...

Laters,

Demo:hail:

 

Well I've tried everything else. Hey.. you never know.

 

It's what the pickup coil "picks up". Inside the distributor, attached to the distributor shaft itself. Turns when the engine turns (in an ideal world).

 

I got a another new coil, cap and rotor. Going to put them on today. I will check the reluctor again to see if it reads ok.

 

To all who have helped me with ideas, Thank you. I found the problem. A Broken Distributor Cam Gear. I could not believe it. I thought I would check to see it the rotor was spinning and shure enough it was not. So thank you all again.:yourock:

 

That can be a simple fatigue failure, or a sign that something is wrong with the distributor (not common) or oil pump (more common).

Some things to consider:

Is the oil viscosity too high for the ambient temperature ?

Is oil pressure excessive?

Are you using a high volume pump?

Is the pump relief valve operating?

Did the pump ingest particles from a recent component failure or repair project (like gasket material, timing chain fragments, etcetera)?

I'd hate to see you go through the same thing all over again.

 

It's a high volume pump. but it seems to be in working order. Primes up just fine. The motor I had just put it together 8 months ago and I know nothing else got fatigued. I've always used 10-40 in my cars. Never a problem. I had 10-30 in it once. Got to hot so I switched back. All I can say I'll wait to see if how it's doing in a few weeks. I keep checking everything to make sure.

Thanks everyone!!

 

just wondering about the distributor gear. mine is busted too. how bad was yours mangled. did you flush the engine was the camshaft gear intact i need help and woukd really like to know what you did after you found the problem. a guy at the parts store said i had to pull my engine and all sorts of crap i'm realy anxious to know what to do any help would be mostapreciated. i have a 5.0 5spd thanxs

 

zstreet, glad to hear your car is running fine. I just wanted to ask you if you had an aftermarket oil pan, or a stock one. I've heard of quite a number of people who have run their factory oil pan dry on a WOT run with a high volume pump. In general, it doesn't help any in a daily driver.

 

When I find this happening I check the cam shaft teeth to see if any damage. Pull dist. and look at every cam shaft gear teeth. Should Have not marks or damage! use Mirror flash light, bump engine, check every tooth. Then I use a oil prime shaft to check the oil pump drag, has a fair amount, but no bad spots.

Next check timing chain wear, remove dist. cap bump starter to line up timing marks to top dead center. Then with the engine moving one direction, note the spot on the timing indicator. now watch the dist. rotor and hand turn the engine back slightly till the rotor moves and note the distance the timing marks have moved. Do this a few times till you know how much play it has. I don't want more than 1/2 inch. New or good will be about 1/8 to 1/4, I'm very concerned if it gets more than 3/4 to 1 inch.

Also crank the engine and watch the dist. turn. it should be smooth and even with the starter cranking. Snappy is a problem!

(During any cranking disconnect the Dist. power.)

Most GM dist. don't break the gear!

Also check the bottom of the dist. inside the housing to see if anything is getting eaten up, or jamming.

If the Rotor is not a ac delco or of very good quality it can cause the lower parts of the dist. to rust.

Have Fun!

 

my dist gear is pretywell worn. might that have caused it to break? i will check the steps you mentioned and go from their. once you figure all that out are their steps to take to such as flushing the engine to remove any particles?? any steps that should be taken while reinstalation?

these distributor gears don't usually break as i've been told would the wear be enough to do it?? thanks for the help

 

Find or make a magnetic drain plug.
Drive 100 miles and check it, Keep the magnet clean.

If you find major metal, Stop! Tear Down now!

Minor amounts so-so Ok, also, liquid silver-metal-look so-so Ok.

There is also a oil filter adapter which has massives magnets to help the filter hold the metal, till it is replaced.

These are item I use on a good engine.

Safety first!

my e-mail avantihall@sbcglobal.net