Have ya ever heard the saying about "A plumber's pipes always leak, a carpenter's house is never finished, and a mechanic's cars are always broke"? Well, that's me this week.
We've got 5 cars right now. 2 'Vettes, the Mercedes, the 'Burban, and the Cad. At this point, only the Mercedes and my '74 are 'dependable'.
Mama wrecked the Cad a few months back, so she was driving the Merc. Then, the new engine I put in the 'Burban a year ago developed a dead cylinder.

So.......I got the '85 'Vette(the"Katmobile"), which hadn't been driven in 3 years back on the road for Mama to drive, so I could have the Mercedes. I stay so busy most of the time, I just don't have the time to fix my own cars, plus, that's what I do all day long.

Tuesday, about 4pm, I gets a call from Mama. "I'm sittin in the middle of the street, and the car won't start"( )! While I'm talkin to her, I hear some guys ask if she needs some help, and does she have a cigarette. "NO, I don't". Well, how 'bout some money for gas?..........You get the picture! I haul to the house and get the 7 cyl. 'Burban, and go to where she's stuck, play around with it for a while, and then just tie a chain on to it and drag it the 2 blocks to the house.

I get the fuel press. gauge hooked up. Yup, gots pressure there. So I decide it has to be an ign. problem. By then, it's late, so I give up for the night.

Wed. nite, after work, I want to get the car up closer to the garage, so I can work. Move the '85, pull the 'Burban out. Start the '85, back out in the street,it dies! Won't start. Get Mama to help push the turd out of the street.
Get the shop manual out. Troubleshoot the "Cranks but won't start" section.
1) Check spark. Put my spark tester on it, spin it over. Yup, got fire.

2) Install injector tester(noid light). Crank it over.....Injectors NOT firing!! OK, now I got something to work with.

Take the dist. cap off, disconnect EST bypass connector, probe terminal "B", circuit #430. Noid light flashes! Cool, the ign. module is bad!!
Now, I've got the Cad. sittin here I can't drive, does it have the same module? Pull the cover off the coil, and yes!!! Same color wires, so it will work. Swap it out, and VROOM!!!

Spend $100 bill today on new module, coil, cap & rotor. Get home tonite and swap the Cad stuff off with the new stuff. Fires right up. Come in & tell Mama I'm gonna take it 'round the block. Get in, NO START!

Then it does start, and I cruiz it down the road. Runs OK. But........will it stay running? I'm gonna take it to work tommorrow, so I guess I'll find out. I just hate to have Mama stranded anywhere. She has a habit of letting everyone know that her husband's a mechanic, but his cars never run! Adams' Apple38604.8257986111

The Katmobile lives for one more day!!!
Drove it to work today w/no problems. Fingers remain crossed.

Great news! hope it keeps on running!

Sounds like a typical weekend around my house, Joel...

JR

SOB!!! The '85 left me & Mama stranded today!!! Just up & died on me, of course, right in the middle of the turn around, under an overpass, with 10 cars behind!
Had to call my tow service & have it drug to the house. And you know, it fired right up when we got it here.
I'm thinking its gonna need a 'puter, or maybe the ign. switch. I've got some testing to do tommorrow
Wishes me luckies!

Well, I'm at the point where I don't really know which way to go, now. I spent an hour Sun. pulling the dash apart to get to the 'puter. Surprize!! Someone has installed a performance "chip" in it sometime before we bought the car('98).

I looked at the circuit board, and didn't see any obvious signs of damage. No nasty smells, no exploded components, no loose connections, no water contamination.
I'm stuck now trying to decide if I have a problem with the:
1)TPS sensor
2)MAF sensor
3)Dist. pick-up coil
4)Bad ground/power connection somewhere

The real problem is, it starts & runs fine now, which makes it hard to determine where the trouble is. I'm afeered to take it out on the road, only to have it crap out on me again, but I can't fix it if I don't know what's causing it to kill the injectors. The factory manual troubleshooting trees only address "hard" faults, not the intermittent stuff.

I hate to blow another $100 on a 'puter and it not fix the prob.
Any ideas/suggestions/past experiences with the same prob.?

The car is an '85, and I have 3 scanners. The problem is, it does not set any codes at all, and all of the sensor info shows to be correct. I'm basically flying blind, here. I do know that something is killing the injectors, but, as long as it is starting and running, I can't determine what. Everything I have checked(after changing all the dist. stuff) checks OK.
The first day this happened, it would not start at all, so I was able to go down the troubleshooting tree, and determined the ign. mod. was not sending a reference pulse to the ECM, and that kept the injectors from firing. Now, I don't know what the heck is going on. I'm leaning toward either a bad ECM, or a corroded connection somewhere.

Joel, I would start with removing the performance chip.  Granted that means getting the correct prom, unless the performance chip is an plug in at the harness add on.   I have seen them create the problem.

Last year my Celebrity did similar nasty duty to me.  I found the injector pulse was dropping to 2.2 ms during cranking, and less running (stalling).  It was intermittant.  The car requires a injector pulse width of about 12 ms to fire up a cold engine on a 70 deg day.  I also had bad TPS and Map readings on a scanner, without any codes.  Doing pin point testing backprobing the ECM I found the scan tool did not agree with the TPS and MAP signals shown on the serial data when the problem was present.  If it was running, they did match.  I had a faulty intermittent ECM.  No problem after I replaced it.

So take a look at the inj pulse width and see what it's saying key on engine off.  That should be the cranking pulse width value.  It may be a good clue.  At the same time look for an RPM sigal on serial data while cranking.  That will tell you if the ignition input is there from the dist on the EST circuits.   Be sure you crank long enough for the scan tool to respond and get a fresh sample to show the data update with rpm info.  A short crank won't show a good rpm signal.  Give it at least 10 seconds cranking time to watch the RPM data.

Let me know what you find, and we'll go from there.  If you want, send me an e-mail and I might catch it sooner if I don't get back on here right away.   Either bunky44221@yahoo.com :  kstyer@neo.rr.com :  kstyer@starkstate.edu.