LT1 Help

[ryanwarby01]

I am at the end of my road with this motor. I am getting a high RPM misfire that gets worse the warmer it gets. I've done a Dynaspark opti, new MSD Coil, new AC Delco ICM, new AC Delco O2 sensors, new AC Delco plugs, new Magnecor plug wires, new AC Delco TPS, and new IAC. I sent the opti back to Dynaspark to check it and it checked out fine. It runs worse with the MAF unplugged. I think that's everything. If anyone has an idea what it could be or knows a place I could take it to get it checked out. Thanks!

[nascarnate326]

Is the MAF clean?

Any vacuum leaks?

[1slo_camaro]

/\ X2 Clean TB, MAF, check for vacuum leaks, and as dumb as it sounds throw in a new PCV valve. only a few bucks and i noticed a little change when i swapped mine awhile back

[ryanwarby01]

The MAF is clean. I also put a new PCV filter. I checked for vacuum leaks, but I could have missed something. Is there a specific method for doing this?

[2EVUL4U]

May be a failing PCM

[ryanwarby01]

May be a failing PCM

I wondered about that, but I wasn't sure how to check it.

[98blackbeauty]

Sounds like you've done most everything, but you might have the injectors checked and flow tested. If those check out you might try and swap the pcm with someone.

[ryanwarby01]

Sounds like you've done most everything, but you might have the injectors checked and flow tested. If those check out you might try and swap the pcm with someone.

My injectors are only about a year old. I will try to find someone to swap pcms with. I have the hotcam, but i think i will be okay to try with a stock tune.

[2EVUL4U]

The Hotcam is a fairly mild cam, so you should be able to do the swap (with the stock tuned PCM) for diagnosis purposes.

[ryanwarby01]

The Hotcam is a fairly mild cam, so you should be able to do the swap (with the stock tuned PCM) for diagnosis purposes.

Will any 1995 lt1 pcm work, does it have to match my m6 or will an auto work? Does it even have to be a 1995?

[98blackbeauty]

94 or 95 because they are OBD1.5. I am not sure if auto will work with 6sp, I would think so you won't have rev lock and skip shift though. be careful going to 5th gear. Does car miss when sitting still and reving it or only under a load? (Driving) Could be valve lash too, of valve spring float.

[ryanwarby01]

94 or 95 because they are OBD1.5. I am not sure if auto will work with 6sp, I would think so you won't have rev lock and skip shift though. be careful going to 5th gear. Does car miss when sitting still and reving it or only under a load? (Driving) Could be valve lash too, of valve spring float.

When I first start it up and rev it up, it doesn't miss, but the longer I drive it the worse the miss gets.

[gary]

Check your fuel pressure.

[blacklt1firebird]

if u need a pcm to swap im in the troy area and i have a 95 6 speed... its stock tuned but its worth a shot if u want

[ryanwarby01]

Check your fuel pressure.

Checked my fuel pressure and it stayed right at 40 thru high rpms.