I have been struggling with some issues at or around idle for a while now. After about three pressure tests, hunted down and found hopefully all of my boost leaks etc. etc., I am still experiencing an inconsistent surge at idle. Mike Sergeant was kind enough to do some data logging for me yesterday. What he found was that every time my fans would cycle on the ECU would hunt for air/fuel. Other than that the idle is fine and of course the SS tune is rock solid. It seems to be something mechanical or electrical that coincides with the fans cycling on. I did recently upgrade my radiator but I do not think this is contributing, but than again I am no mechanic: soooo……………any guesses?
unplug a fan then test, then plug it back in and unplug the other and test. Maybe a fan is the cause. Why I don't know as I am no mechanic either.
If it's a short ram, the fans could be blowing on the air filter making it "trip out" a little... Siegel
No short ram here, stock air intake with a K&N drop in. I have ej205, ported upper intake, tgv deletes with phenolic spacers, rerouted fuel return, Hard pipe turbo inlet, 16g, cobb boost solenoid, Mishimoto radiator. All exhaust components replaced other than the header. I was thinking maybe a ground issue. The battery to chassis ground looks good. I did not look at the one that connects to the bracket under the top mount yet. I have a NAPA battery that I recently installed. The positive clamp did not fit on the positive battery stem. There is a red plastic spacer on the positive battery cable clamp it would not allow the clamp to grab the stem so I removed the plastic spacer and then it clamped down. I don't know if this would effect anything but you never know. I should not have any more boost leaks. King checked for exhaust leaks last week that was all good.
Keith at Zen fabricated and installed a NICE ground set up and I cleaned the MAF and IAC. One of the three or all three fixed it.