88IROC_Z

the other day, about 3days ago, my car stalled and died and wouldn't start. I towed it home and it was the ignition fuse.I replaced it and it worked til tonight.
Then tonight I went to my dads house and as I pulled up it died, I replaced the fuse and it idled for like 10min. in the driveway, then I went to drive home and it died like 7 or 8 blocks away. replaced fuse and it turned on then died, replaced it 2 more times and it would just barely turn on and die. called my dad and went to go get a tow strap, when we came back I put another fuse in and it started then I took off and didn't even make it down the block-towed car home and there it sits.
I have the AIR disconnected and tie strapped to the fuse box wiring and nothing is hitting my headers if that helps any, and i visually inspected everything and it "seems" fine.
I have also posted on another thread that was similar, but they never actually posted an answer.
any suggestions???????

Green96Z

Year and make? Hard to help if we don't know these things, wiring is different for several years.

88IROC_Z

sorry I meant to put it in my sig, but I forgot
96 Z28, M6.
I was working on it today and I found that the battery to chassis ground was not getting good contact.
I scuffed the paint to bare metal and regrounded it, I also ran an 8ga. ground from the batt. to body ground next to the battery to the ground where the coil is grounded and it helped, then I started the car and it turned on fine, drove around the block and then I stalled it a little when I pulled up to my house and it turned off and blew the fuse.
I put a new fuse in and it runs fine, but I am worried it will leave me stranded.
Also don't know if it has anything to do with it but it runs VERY rich at idle.

88IROC_Z

Ttt

hosspwr94

this is a tough one... if you have any aftermarket alarm or stereo stuff installed I'd check the wiring on that stuff to see if something has rubbed through and grounding out a bare wire, the other thing would be to start checking the wiring harness under the hood for any bare spots, this is not a common problem but its a possibility

88IROC_Z

I have already checked all the wiring, I went pretty far back into the wire loom on the drive side og the engine also as well as checking the wiring that goes into the pcm.
As far as stereo wiring I do have an aftermarket deck in it, but all wiring seems to be fine and the radio and many other things still work even when I blow the fuse so it does not seem to be on the same circuit as anything else I have checked.
the car seems to only do it now if it has a load on it or if I "stall" the car.
Also I don't know if it has anything to do with it but there were two wires that looked as if they were tapped into on the PCM harnesses, they were both white one on the red connector #13-which I think is the tach output, and the other was also white on the blue connector I think, which I think is the skip shift lamp control, it seemed as though they had T-taps in them and I just taped them up.

Injuneer

Did you check your Owner's Manual for a list of all the devices on the fuse that is blowing? Did you check out all the devices, and their wiring?

88IROC_Z

No, I do not have an owners manual, I did not notice anything else having problems when the fuse blew. I have also checked the other fuses and have not had any problems with anything else.
I have a second harness for another LT1 I have and I traced where the wiring on that harness goes from the fuse box and checked it out on the car as well, as well as the engine harness'
Does anyone have the list of accesories i should check from the manual, or any other leads.

shoebox

You can get an owner's manual in pdf form from my website link http://shbox.com/pdf/manuals.html .

The IGN fuse (11) feeds
ICM
Crank position sensor
coil

88IROC_Z

thanks, I think I got alot of the diagrams I have from your site, it is a very resourceful site, I am downloading as I type, I am on lunch and am about to go back to work, but I will check these circuits after work today, and thank you for you help guys.

88IROC_Z

it shows ignition usage:
V8 VIN P: Ignition Coil Module,
Crankshaft Position
Sensor, Ignition Coil

I have already checked all of this wiring and it seems fine.
One other thought is I was told by the previous owner that the car was tuned, could there be an error somewhere in the tuning causing this problem?

Guest47904

Does the engine have to be running for the fuse to blow or will it happen with just the power on but engine not running?

88IROC_Z

It has only happenned with the car on, I have not actually left it sitting with the ignition on long enough to see if it blows.

hosspwr94

I have never experienced this but could it possibly be the coil causing problems? just thinking out loud!!

Guest47904

So why don't you???? It may make troubleshooting a lot easier.

Then you can unplug one device at a time and see if the fuse remains intact. Better yet, put an ammeter in place of the fuse and do the same thing. The one device that drops the current the most might ultimately be the bad guy.