latest update guys:
MAF and TPS both check out perfect with the multimeter. unhooking the battery for a while after changing the IAC valve did seem to help quite a bit.
I put a vacumn gage on it, it idles at a steady 18in.
I pulled the vacumn line off the FPR, looks clean and dry, no evidence of fuel.
I have sprayed stuff all over the intake and all connections, I have poked and looked everywhere, I see no vacumn leaks.
I was playing with the EGR too, if you pull the vacumn line, put your finger over it, then start revving the engine(warmed up), shouldn't you get vacumn, as in it is trying to open the valve?
Let me explain all this in another way:
1. something is causing the IAC to not work at all sometimes (as evidenced by the ultra low idle (about 600) sometimes/most of the time).
2. something is causing an instant bad lean condition (as evidenced by the back popping in the intake pipe). 95% of the time this happens, the IAC decides to take over, and kick the RPM to 1500 or better. although occasionally it will pop a couple of times without the RPM change. this might happen while sitting there idling, or it might happen while driving down the street in a light throttle condition. this stuff might happen 10 times in 10 or 15minutes, or it might not happen at all for days. (but the low idle is still there usually)
thanks for any and all help.
