4G63T Will Not Idle unless throttle is depressed...WTH???

[Soular]

Hey guys.... My 2G GSX will not Idle at all... it goes from 2000 rpm if my foot is in the throttle to 0 and shutdown if I take my foot off the the throttle. It's as if I am using the key to turn the engine off. THe Electronincs continue to run ... so I doubt if
iit's electrical... but I don't know... Any Ideas?

My Story below.

The Car seems to have some odd idle issues as well as random stall and shutdowns at cruise speed. For the most part the car will Idle steady at 750 rpms (Set via DSMLink).

Then the car out of the blue goes full stupid... I have listed the issues below... Starting with today's issue first....

Issue Three (Today's Issue)

Today I was driving... and while at high speeds (65 -70 mph) on the highway I notice nothing odd... then when I came off the ramp into the city stop light areas the car shutdown as soon as my foot was off the throttle and the car was out of gear.
Coasting to a stop.


2000 Rpm straight to 0 rpm shutdown! WTH???

I reboot and the car does the same thing... rev the engine to 2500 rpm
and as soon as I come out of the throttle the car shuts down....

Restart.... and don't press the throttle the car shuts down....

as along as the car is not in gear it will shut down if I am not on the throttle...
This is a very new event...

IF the Car is gear and rolling the car will contine to run until the speed is very slow...
then it wall bog down and stall to shutdown.

Other issues that are now side issues

Issue One:

I will be driving around 45 mph and all of a sudden the radio will turn off and all of the dash warning lights come on and the car shuts down and restarts by itself. I guess because the car is in gear and you have a wind milling effect and it restarts itself.


Issue Two:

Out of the Blue the car while not moving at a light or a stop sign, the idle will surge and stay at 1500 to 2000 rpm.... even if you shutdown and restart it jumps back to the high idle rpm... Then after a while it will go back to 750...
sometimes by the time I get to the next stop. This happened the other day....



I had a forth issue that seems to have fixed itself... If the compressor was on
for defrost or the AC the car would idle very low and stall...
Now that seems to have fixed itself.


I was able to get the car to idle at 200 rpm on my last restart attempt...
but it shutdown after a few cycles...

I drive the car less then 2000 miles a year but I start it up every now and again
and run all the system to keep things working... But I have something very odd
going on here...

Any ideas...


I did a full forum search and read thru 20 pages of idle issues and did not see anything like this...

Thanks in advance -Bones

 

[#40Fan]

Sounds like a bad idle air control or a possible vacuum leak.

 

[StreetTunedTSi]

Sounds like a bad idle air control or a possible vacuum leak.

yup

smoke test it if you have access to a smoke machine and check for a vaccum leak

 

[DeadsEvolution1]

Like they said, It's either a Vacuum leak or a bad boost leak. I had a throttle body leaking so badly that I could keep my foot on the gas and it would stay on but once i took my foot off the pedal the car would die. Boost leak test the car asap

 

[dsmspickdad]

Sounds like ISC, throttle leaking, ISC not adjusted correctly, Vacuum leaks, throttle plate not correctly adjusted, and last faulty fuel regulator. I had the same problem found that I had a faulty regulator, the last thing I check, wasn't closing at all.

 

[Soular]

Many thanks for all the info. I will test some stuff and post my findings ...

Thanks again. -B