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-   -   89 Vette will not start help needed>>> (https://www.corvetteforum.com/forums/c4-tech-performance/93458-89-vette-will-not-start-help-needed.html)

-=Jeff=- 07-24-2001 09:58 PM

Okay,

I had to fix a rocker problem on my vette. I got it done and went to start the car. it started and ran for about 1min before I realized I did not tighten the 10GA power wire going to the Alt. Well I tightened it but now the car will not start. it seems to want to.. I try and it chugs, sputters and Dies..

Here is what I have done to check it so far:

- Triple Checked Firing order.. it is correct
- Checked all Fuses at Fuse panel.. All good
- Checked all Fusible links near the battery..all look good
- Checked Spark.. I have spark
- Checked for fuel.. pump is running and fuel is present at the rails.
- Checked ECM.. No codes other than the standard code 12
I need some more advice on things to check. I have replaced the coil.. same thing. Could I have spark and have a bad Ignition Module?

One other thing I noticed.. When I try to start the car the security light flashes.. I never noticed before.. Is this normal?

Also my VATS is disabled



-=Jeff=- 07-24-2001 10:38 PM

Also swapped ECM.. no change

checked TPS voltage (per Service Manual) set at .52

removed MAF connector (per Service Manual) no change


HighHopes85 07-24-2001 11:34 PM

This generally won't make a hill-o'-beans difference but how did you wire up the new coil? The stab-tabs usually do not come pre-bent so you have to bend em out yourself. In the early model HEI's, the 2 wires have to cross instead of going straight to the bat on one side and tach on the other. Don't know about the '86+

Also, the old coil could have been bad, but the new coil might have had the wrong wire leads. GM color-coded the ignition coil to the bat and tach leads on the coil under the cap.

Yes, a GM ignition module could cause that because not only does it control the spark but also the saturation and the dwell. I used to test a bunch of GM modules. They were either bad right off the bat or they took about 10 cycles on the tester to heat up before they failed. AutoZone tests them for free. Make sure they run it at least 12 cycles.

Only other things I can think of are the coolant temp sensor at the front of the plenum under the TB or maybe the MAF plug. If the CTS is unplugged, or even jostled wrong, the computer will most likely try to start your car up thinking it is at -40*C. The CTS for the ECM is different than the one that the gauge reads.

Also, since you have a multimeter evidently, put the doomahickie on Ohms and read from A-B, B-C, and C-A on the TPS sensor itself when it is unplugged. The 2 smaller readings should add up to the larger reading or at least be pretty darn close. If you have a GM manual, disregard the schematic they give for the TPS because it shows the wrong potentiometer points.

Oh, maybe your IAC took a vacation. Might want to reset that. -Matt-

BTW, the battery connection didn't fall off the cap, did it?

-=Jeff=- 07-25-2001 10:27 AM

Matt,

I checked the TPS but will check it again tonight or tomorrow

I will also check the CTS. It looks okay and looks to be plugged in correctly.

As for the Coil. It was a coil that was fine when I pulled it out of my old motor. and I have it wired the same.. the red and whit wires look to cross over.. red feeds from Bat and the white is the tach.

I will get the Module checked.. As for the Bat wire on the cap.. it is solidly plugged in.


It also seems like the car wants to run.. but does not have enough spark to keep it going.. when I try to start is sputters until I shut the key off.. my best guess at this point is the module.. but I wanted more opinions

Jeff

Vic'89 07-25-2001 10:32 AM

Jeff

Pull out a spark plug and make sure they are not soaked with fuel. This sometimes happens from cranking the motor alot and not starting the car.

Vic


-=Jeff=- 07-25-2001 12:02 PM

yeah I will check the plugs next chance I get.. Does any one know where I can find out how the ignition module actually works?


89vette 07-25-2001 12:48 PM

I agree with VIC. Try revving the motor to belch out any excess fuel. Did you shut the car off when you tightened the wire? When your linked with your PC, what are you showing? Pulse width, timing advance, MAF?

Are your plugs wet? Is your ESC wire plugged in? I know your not stupid but is your MAF plugged in? Usually the module either works or doesn't. That's what I have always heard.

Keep us posted. This must be the "89 No Start Month"

Jason

-=Jeff=- 07-25-2001 12:58 PM

Jason,

I cannot get it to rev at all..

Maf is plugged in.. I check that last night. ESC is also connected.. I need to reconnect my PC and record the data.. I forgot to record it yesterday. I will not get a chance until thursday evening to mess with it again. I also found out that it is possible that the Ignition module ould be bad and still have a spark.. I am going to get the Module tested on Thurs as well. I plan to pull the Module tonight and get it tested tomorrow afternoon.

Yes I did shut off the car to tighten the wire..

I will keep everyone posted

-=Jeff=- 07-25-2001 06:47 PM

small Update..

The wire I had not tightened to the ALT runs through a Fusible link to the Jumper block near the Battery. I would think the Fusible link would go first.. since it is the first inline if there was too much current or something. Well it ohmed okay. http://www.corvetteforum.cc/ubb/frown.gif

I am going to get the Ignition Module tested tomorrow.. hopefully that will be the problem

Jeff

PeteL 07-25-2001 07:29 PM

Jeff, I'll bet with the 'load dumps' caused by that loose connection you probably erped (that's a technical term) some semi-conductor somewhere. Scan tool would be telling perhaps.

Good Luck,

Pete


DOCTOR J 07-26-2001 12:22 AM


You might check for oil pressure - ECM needs to see some oil press to hold in the fuel relay after initial cranking. Maybe you knocked the wire off the oil sender? HTH

DrJ

David-F 07-26-2001 01:08 AM

The oil pressure fuel pump switch is a back up system the ECM controls the fuel pump relay, it gives it a 2 second prime before it starts and then turns it back on when it gets an RPM. It could realy be a lot of things. Is there a groung strap on the coil? A bad MAF relay were the MAF is not turning on? The fact that you have said it ran then you tighten the alt. stud then it did not run makes me think it's electrical. You swapped ECM so lets rule that out. I think from what you have told us you have unpluged the MAF sensor and tried starting and there was no change. Do you get a "check engine" light when you turn the key on? How old are the MAF relays you may have to replace them. Get an old plug and hook it to one of the wires and crank the engine over, how does the spark look? Blue with a good constant spark? Are you getting an injector pulse? Are the plugs getting wet? If you spray gas in the intake will it run better? Hook a timing light up and see were it's tring to fire. Let's see whats working and whats not.

David Fulcher

-=Jeff=- 07-26-2001 09:42 AM

David,

I replied to your email..

I will check these other things you mention here tonight...

Jeff

nobodyunknown 07-26-2001 05:57 PM

No one has address the statement about the security light flashing.
Are you sure your alarm hasnt been turned on?
If it was the alarm you probably would'nt have any spark so I guess I answer my own question.
Do keep us posted.

-=Jeff=- 07-26-2001 07:27 PM

it is fixed...

http://www.corvetteforum.cc/ubb/Foru...ML/010621.html


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