Car runs bad after idleing!?!

[Peg8687]

After a long road of R&R parts...the car is running noticable better after a new alternator (stock) Voltage didn't seem to change to much but the old one test to have a bad Diode.

But now you can go out and drive and its fine. But if you have to stop at a light when you take off it has a HUGE power loss, and when under load the shifter shakes violently and the intake pops then it smooths out but still not as strong. Turn the car off for a few secs then back on its fine until u have to stop and idle for a few...Like stop signs is fine, but at Lights it normally gets it..

 

[Peg8687]

I also noticed when i rev the car a little...when i goes back to idle it drops to about 500 then goes back to ~800 with its idles....so it rev and let off it goes to 500 then up to 800...

if that has anything to do with the problem stated above IDK lol

 

[Peg8687]

ttt

 

[mustang90]

When was the last time you changed your oxygen sensors?

 

[NKau]

I was going to say the same thing. How does your car run when you first start it up cold? If it seems to run well, and then starts running crappy when it warms up, then it's most likely your O2's. When you first start the car the computer is in open loop, meaning that it's not taking readings from the 02. After it warms up the computer goes into closed loop and make adjustments in fuel based on what the 02's are telling it. At least that's how I understand it........

 

[mustang90]

You hit the nail on the head, NKAU Can't be said any better