weird idle issue

**occamaroz** · 06-06-2007, 09:18 PM

Once the car goes into closed loop the idle drops a little a few secs after stopping. Then a few secs later it revs back up. I only drops maybe 100 rpms. Also when looking at my predator live data the 02 sensor readings drop to double digits. When the idle goes back up the 02's go back to 3 digits. The 02's sensors have maybe 35k miles on them and my gas mileage has goneup slightly. If I unplug the maf the problem goes away but the maf is less than a yr old and even with another maf I have it still does this. I tested the maf wire hardness and it reads fine. Could it be the ECT sensor possible or something?

**sic2001** · 06-07-2007, 07:37 AM

I have the evact problem, Ive changed maf sensor, cleaned idlesensor, changed plugs to denso iridium and wires, seafoamed the top end, replaces o2 sensors ,had a new cat put in (under warranty) and still get a shimmy idle after warm up. When I bought the car with 30,000 miles on it it was perfect, then I put a lid and induction system on it and it started doing it after. Cant see why that would effect idle once the computer relearned though. Let me know if you come up with a cure or an idea we can try.

**0rion** · 06-07-2007, 08:18 AM

Originally Posted by occamaroz

Once the car goes into closed loop the idle drops a little a few secs after stopping. Then a few secs later it revs back up. I only drops maybe 100 rpms. Also when looking at my predator live data the 02 sensor readings drop to double digits. When the idle goes back up the 02's go back to 3 digits. The 02's sensors have maybe 35k miles on them and my gas mileage has goneup slightly. If I unplug the maf the problem goes away but the maf is less than a yr old and even with another maf I have it still does this. I tested the maf wire hardness and it reads fine. Could it be the ECT sensor possible or something?

this was actually what I was thinking. Can you look at ECT with the predator? I would maybe give it a look and see if it looks out of line. Kind of a longshot but worth looking at.

**occamaroz** · 06-07-2007, 01:09 PM

I was trying to test the ect sensor yesterday with a digital multimeter I have but no readings when cold. I will have to test it when it's slightly warm and get back on here with the results. I have instructions on different sensor testing.