Odd starting problem
Thread Starter
On The Tree
Joined: May 2009
Posts: 167
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From: dayton, ohio
Odd starting problem I have been havin odd starting issues with my 95 z28. I have recently replaced my optispark with a ac delco unit, plugs and wires and the icm. Fuel pump and filter have recently been changed also. And for awhile the car ran great. And it still does once it finally starts. But the problem is it takes maybe about 10-15 seconds to finally crank up. The volt meter drops when you try to crank it and when it finally does turn on the rpms sometimes jump to about 1500 a couple seconds and drop back down. And then the ses light comes on. But it runs fine. No miss or sputter and no loss of power. And also sometimes when I come to a stop when it's cold the rpms jump up and down. And at every stop light the volt meter drops a little but goes back up when I take off. This is really confusing me and I can't figure out what's causing this
OBD I with an OBD II connector. Have it scanned and see what code is stored. I'm going to venture a guess you have a code 42 set... which could be a couple of things. maybe as simple as a bad coil wire, bad optispark pigtail (from pass. side intake to opti) or possibly a failing ICM.
How far does the voltmeter drop at lights? It's supposed to drop a tiny bit since the alternator is turning at 650-800 RPM instead of 2000 RPM cruising. Unless that's going below 12 volts I'd dismiss it as coincidental. Ideally you'd want to see about 13-14 volts all the time. These cars come with a 140A alternator but it's possible to get one lower from a parts store if you don't specify and they don't know.
Get the code pulled and post back up...
How far does the voltmeter drop at lights? It's supposed to drop a tiny bit since the alternator is turning at 650-800 RPM instead of 2000 RPM cruising. Unless that's going below 12 volts I'd dismiss it as coincidental. Ideally you'd want to see about 13-14 volts all the time. These cars come with a 140A alternator but it's possible to get one lower from a parts store if you don't specify and they don't know.
Get the code pulled and post back up...
Thread Starter
On The Tree
Joined: May 2009
Posts: 167
Likes: 0
From: dayton, ohio
Ok ill try to pull that code. Damn complicated 95. But I never really read where it drops but it goes just a couple notches below the halfway mark and sometimes even lower than that. And I'll check those parts you named. Thanks for the help
Thread Starter
On The Tree
Joined: May 2009
Posts: 167
Likes: 0
From: dayton, ohio
Ok I parked the car and have not touched it since. But how do I get this thing scanned with it being an obd 1 PCM with this obd 2 port? All the scanners say error when I try to scan it
