Hondata

This car has been in and out of the shop w/ head gasket related problems. Last tune everything was perfect. Now we're retuning the same map as before, the engine will only idle in columns 4 and 5, sometimes 3 and 4.

The engine is B18 non vtec, 8.5:1, crower turbo cams, skunk2 intake mani, air research turbo (unsure, but smallish), MSD SCI, MSD Blaster 2 Coil, RC 650cc, and nothing out of the ordinary. The tps is @ .488v fully closed and 0% on the ROM editor software. TP% reads 99% at WOT. The car has an enlarged OE throttle body (minimal boring). Base ign timing is set at 15btdc. There are no other changes that I am aware of.

Are there any common causes for this?

Well, I think it has something to due with vacuum at idle and these cams. It's funny though. We tuned on these cams before and didn't have this problem at that time. I'm gonna put some more vacuum on the MAP sensor and see what happens to the highlighted cells at idle.

Have you done a leakdown and compression test?

No leak through or compression tests yet. I'll post the updates. Thanks!

At 24 inches of vacuum with a tester/pump, the highlighted cells move into the 1-2 columns. At idle and cold, the engine only produces only 17 inches. Warmed up, the engine produces about 15 inches.

I think I found the problem.