BlackShelbyGt500

i don't know whats going on with my car. so when i start the car it starts fine it goes to about 1200-1300 rpm on cold start then it goes below 1000 rpm and its stable. now once i shut it off and start it back up it goes on a high rpm revs about 1400 then drop back down to 900 then my car start to kinda shake a little bit and it feels like it wants to shut off then all of the sudden the rpm goes up again around 1300 to 900 then back to 1300. and i feel like my exhaust is clogged up. i hope someone knows what i'm talking about. i used to have a tune in it with a steeda cai but i put it all back to normal because it was trowing a p171 something code.

edwin108

Try cleaning your throttle body and resetting the electronic throttle.

BlackShelbyGt500

how do i reset the electronic throttle

edwin108

Copied from another forum:

1. Turn on car without starting the engine
2. Wait til the dash lights stabilize (some of them will turn off)
3. Step on the gas pedal in one smooth and steady motion
4. Once gas pedal hits the bottom, let go
5. Turn off car and wait 4-5 seconds
6. Turn engine on
7. Drive
8. Repeat 1-6 if it doesn't work the first time

808muscle

171 is a lean code. Your either have a air leak ie the motor is getting unmetered air into the intake or your not getting enough fuel. Check that cai for leaks. When was the last time you changed the fuel filter?

Nuke

I'd certainly clean the TB and replace the fuel filter as suggested above, but also run a tank or 2 of SeaFoam before considering any other more expensive work. How many miles and were the plugs ever replaced?

BlackShelbyGt500

42k and what plugs are we talking about? on my first start up its fine its the second start up that has a problem