ok so first off i have a 2003 with vortech, 5/16 plenum spacer, header back exhaust, ssbox. i have been having problems with the idle so i decided to take my plenum off and retorque it back on to make sure i have no vaccum leaks, i also decided to swap my 3.12 pulley out for a 2.87 that i had. i started the car up and it idled fine for about 10 min in my driveway so i decided to take it around the block to see how it ran. i made it half way around, never really got into boost at all, never got out of 2nd gear, and all of a sudden while shifting from 1st to 2nd at 3500 rpm the tach spiked to redline then dropped off i lost all vaccum pressure car went into limp mode and idle was extremely rough sounded like a harley. the 4 cel codes are p1121, p1122 which are electronic throttle control actuators, and p1614, p1615 which said nats malfunction. im not really sure what any of these mean. after towing my car home i reset the codes and unplugged the throttle body and maf and replugged them in to make sure i had good connections then started it up and it seems to idle fine again.. does anyone have any ideas what may have cause this? hopefully i have not done any damage to my car.. please any input would be great.. thanks-

 

did tach just move, or did engine rev to redline then die off?

tom

 

engine revved all the way up then down.

 

hmm, I was thinking the tps's got out of sync, but I thought it would just shut down didn't think it would rev.....lemme think
I'm still thinking vacuum leak somewhere too in the back of my mind


t

 

NATS malfunction is referring to the key... or more specifically the chip in the key.

 

i did read about the nats being a key but it still starts fine with the key so im not sure how that could have been effected

 

if it is tps what can i do about that?

 

Happened with me a while back. The code never showed up after I got a new key and reprogrammed both of them.




Have you tried disconnecting the battery for 30 mins?

 

no not yet, i have done all of the throttle position, idle volume reset though.. and cleared all of the codes from the ecu

 

i am also getting terrible belt squeel now it wasnt slipping at all before it shut down but now it wont stop slipping the belt seems tight enough i will try to tighten it a little more as soon as i can get my car jacked up..

 

belt slip fixed. anyone have any ideas why my car shut down? is it possible that because i put the smaller pulley on and drove it before i did the throttle relearn it caused the tb to freak out or something like that?

 

bump

 

???

 

i ended up resetting everything. put a new throttle body on that i had, put the 3.12 pully back on and everything seems to be back to normal.. go figure.. not sure what happened. but at least it is running now.. the weird thing is the idle is still jumping between 750 and 1000 pulsing but if i turn the ac on it stops and idles at 950 where it should and idles very smooth..

 

cool