porscheka

Ok so i have a 1984 944. It was bought in decent condition for $2,000, but things are starting to go wrong with it. Right now i'm struggling with two problems that i can't seem to figure out.

So here's the problem... When i first start it, it runs fine, but when it warms up the idle starts bouncing from 800 to 1,400 RPMs AND the car hesitates to accelerate. I can however get it to move if i punch it. But if i want to moderatly accelerate, it refuses and it starts to do some subtle jerking motion like it wants to move, but won't.

So my first thought was to replace the Throttle Body Position Sensor. That actually made the idle worse (the TPS is properly tuned or so the Ohm meter says so, it goes from 0 to infinity to back to zero as i slowly open the throttle.) The car still hesitates, although not as much.

I have an oxygen sensor coming in any time now, hoping that will fix it. Any ideas?

mavfan

mines doing the same exact thing, only it hesitates 'n such when it has not warmed up, and then when it is warmed up the idle goes from 800 to 1200. so i guess opposite from what yours is doing? no suggestions tho

mein51

Your problem may be the ISV. Check on Clark's Garage, I believe there is a set of troubleshooting steps to try.

RM512

Could be the AFM, temperature sensor, etc. Good write-upon how to check on clarks garage.

porscheka

Thanks for the info on Clark's garage. I'll be checking the AFM and ISV when I recieve the oxygen sensor, which shoudl be tomorrow or sometime very soon.

944CS

have you touched the idle adjustment screw on the throttle body?

porscheka

yes i did, but I did that when the engine was cold, not warm, so maybe trying to adjust that while warm might make a difference

bearone

do it warm.

87951