ws6 idle issues

**1998 T/A** · 04-12-2015, 09:23 AM

The car is 00 ws6 has LT'S, ORY, no cats and a fast 92 with nick williams 92. The car when you first start up sometimes jumps to 2k RPM. When driving at warm Temps going down in speed form say 65 to a stop it will idle at 2k RPM until about 25mph then dip to 1200 then at 800 sitting still. I unplugged the MAF, TPS, and IAC sensors before driving the car today and it started at regular RPM but about 45 min into my cruise I noticed the idle fluctuating. Now the car isn't tuned yet I believe this is related to not being dialed in etc...but could it be something worse or need to address before my tune on the 21st?

**pajeff02** · 04-12-2015, 12:27 PM

It's getting excess air from somewhere. Vacuum leak, the IAC is acting up or the throttle body is hanging open.

**1998 T/A** · 04-12-2015, 12:31 PM

It can't be a vacuum leak I went through all of that before putting the intake back on. The fenco I got for it was a tight fit so I'll inspect that when I get home and email the dude I got the IAC from and see about a warranty replacement.

***SMWS6TA*** · 04-13-2015, 06:17 PM

Yeah but did you check to see if the HVAC is connected?

Also the PCV system has a lot to be desired, they leak at the y split in the back as well at the PCV.

I did the LS6 VCT on mine (when it was a 98 LS1) and went with a catch can and never looked back.

Has it been doing this since the intake was reinstalled? If so, you might need to take it back off again. The gaskets can get pinched, come off, etc, the knock sensor wire harness can also get in the way if not secured (I used a piece of masking tape to hold it in place). Other vacuum leaks besides the HVAC, intake and PCV are the valve covers for the ports that need to be checks ass well.

Might as well check these too. Pull the IAC and see if it moves, sometimes excess buildup can clog it up, use carb cleaner. Do a TPS reset; disconnect the TPS and turn key on, no start for 15 seconds. Turn key off, reconnect the TPS and turn key on again, no start. Turn off, then try starting.

**0rion** · 04-13-2015, 09:46 PM

sounds like a tune issue to me......your idle airflow tables need corrected for the intake and TB.

**1998 T/A** · 04-15-2015, 05:14 PM

Well the pcv is brand spanking new from the dealer...no catch can and the tb and fernco are on tight...I sprayed around the intake with MAF cleaner and no change in RPMs. I have a tune schedule with Brian on the 21st so I bought another IAC to bring with me incase we need it...worst case scenario we need it and I'm out 89 bucks. The dick on ebay won't even return my emails about it being defective. Granted we are not sure if it is bad it's still shitty of him.

**1998 T/A** · 04-15-2015, 05:15 PM

Oh and HVAC is all hooked up.

***SMWS6TA*** · 04-15-2015, 06:15 PM

should use carb cleaner...

**1998 T/A** · 04-16-2015, 07:22 PM

Both are highly flammable I'm pretty sure you can use either

**RichWS6** · 05-03-2015, 04:15 PM

Originally Posted by 1998 T/A

Both are highly flammable I'm pretty sure you can use either

sounds like an IAC to me too, if you replace it just remember there is a learning curve for the sensor, I think the books say its like 30 miles or something of the sort. Good luck!