I bought my car wrecked awhile back an it had set for a long time before i got it. so when i got it home it didnt want to run right so i just figured bad gas i got new gas in i replaced the spark plugs and wires and it still didnt run right. it keeps idleing werid going up and down and then it'll die. so my bro in law checked the timing and in park it is off bad and then when it is in drive it its right what could this be.

 

Try the free things first...try playing around with the idle adjustment screw, look for cracked vac. lines, etc etc.

 

yeah but would that throw of the timing in park...?

 

No, it'll just up the little amount of air that's already going through the TB. But check all the lines for cracks, rot, or loose hoses...

 

If that dont work, the best, and cheapest way is to tune it. Get ecuflash and evoscan. use evoscan to datalog and ecuflash to pull your ignition and fuel maps..make them better...and put it back into the ecu. Make sure you know what your doing, if you dont..find someone that does because you dont want to mess up your ecu.

 

Nevertheless i believe it is just a cracked or loose hose, if it only does it in park.

 

wheres the idle screw??? I thought only carbeurators had those.

 

The idle screw on a throttle body is an adjustable stop that controls the fully closed position of the throttle butterfly. Usually the throttle won't be fully closed even at idle.

I agree it sound like a vacuum leak. A possible explanation for the timing change would be that the vacuum leak, the effects of which would be greatest at idle, causes a lean condition in the engine leading to knock and the ECU retarding timing to try and remove the knock. Just a theory.

 

How did he check the timing? If you don't mind me asking.

Fox