I have a '95 Z28! I am unforunate enough to live in the great northeast and only be able to drive it for maybe 6 months outta the year. I started the car regularly throughout the winter but then we got buried in snow and wasn't able to get to it. this spring when I went to start it, it wouldn't start. I checked the PCM fuse under the hood and it was blown. As soon as I put another fuse in it blows as well. The car won't even start at all so I can hook up a diagnostic and see what it says. Any advice?????

 

Which PCM fuse - "PCM BAT" or "PCM IGN"?

You have to look at what else is on the circuit of the fuse. According to Shoebox's 95 LT1 wiring diagrams, the PCM BAT fuse also supplies the instrument cluster and the theft deterrent module. The PCM IGN fuse also supplies the MAF sensor, theft deterrant module and fuel pump relay.

http://shbox.com/1/1995_pcm3.jpg

 

the fuse that is blowing is the pcm ignitition one, its the 10a under the hood! I tried bypassing the wire that feeds it from the pcm to the fuse with a new wire and it still blew the fuse. Maybe a bad pcm?

 

Let's try to get this straight. The PCM IGN fuse is not under the hood. It is in the dash fuse panel. What is the fuse labeled and what position is it? There is a PCM fuse in position 8 and an IGN fuse in position 11. Both of them are 10A.

Have you checked any underhood wiring for varmint damage (since the car sat a long time)?

 

He's probably referring to the 10amp Ignition fuse #11 underhood. It does not go to the PCM.

It goes to the Auto tranny, and coil. Unplug the coil and see if the fuse blows with KOEO.

Do the same for the tranny. To help find the wiring problem. If it still blows after doing that. Find the black 10 pin connector near the PCM and disconnect it. Check the fuse again with KOEO. If the fuse didn't blow this time, ohm the pink wire at the connector to ground with tranny and coil disconnected. Find the short to ground.

 

hey, sorry about the confusion. the fuse that is blowing is the PCM bat. fuse. it is the #8 fuse I believe under the hood. as soon as I try to put a new fuse in it blows it. It also has completely drained the battery. sorry for the confusion.

 

Rob - I know in 94 the two PCM fuses were both in the interior/end-of-dash fuse panel. I though in 95 they moved the PCM BAT fuse to the underhood convenience box??? The 95 Z28 Owner's Manual shows the PCM fuse in the #8 position under the hood. But the 95 PCM wiring diagrams show the wiring the same as 94 - both fuses in the interior panel (#4 and #5).

Confusing.

 

Try unplugging the PCM connector B and see if it still blows. It also runs through C100 (seen in this pic) cavity D. Inspect the wiring along the route, if necessary.

The things you have to do to correct GMs documentation. Yeah, they kind of hosed that up. They even show the fuse as 5A in one place and 10A in another. I have corrected my online PCM diagrams. Thanks for pointing that out.

 

Funny thing is.... the only reason I know that is because you posted it a long time ago.....

 

LOL, that's even more funny.