Hello board,

Two months and over 2,000 miles into 914 ownership, I am diggin this Slow Car Fast. My 1.8L runs strong and has received a new fuel pump, filter, fuel lines and vacuum lines. in the pursuit of getting driveability issues resolved. I have also followed a great video tutorial on performing a rehab to the AFM. The AFM was the source of most issues as the contact were in need of cleaning and the flapper door needed cleaning as it was hanging up mid-travel. I have also cleaned the throttle body.

So what I am dealing with now is a car that starts right up when cold and runs best until the engine exceeds some unknown warm temperature. When I say runs best, the idle is 900 RPM and between shifts the RPM drops off as expected. Once the car has been driven long enough, I get the following:

Come to a stop and the idle drops only to 1,800. - blip the throttle and the engine lowers to 1,200.

Once I have driven longer the above behavior compounds with the added issues:

Shifting has the RPM lingers at the level it is when lifting the throttle and disengaging the clutch - rev matching, but no.

Come to a stop, blip the throttle to lower the RPM and it begins to fall on its face, dropping to below 500 and almost ready to stop, a few time it has, so I let out the clutch and the car starts right back up.

With all this, driveability through the power range is fine.

Next I was going to measure resistance through the AFM's different positions.

Does all of this sound sympomatic of something any of you have corrected before?

If so, how?

Thanks in advance for your thoughts on this.

How many vacuum leaks did you already fix? Try finding 2 more.

Which 2 more?
Have the map. Replaced all with new lines.

If the AFM door was hanging up, sounds like the engine at one point backfired, which warped the door. How exactly did you fix the sticky door problem?

I also agree with vacuum leaks. Replacing the lines is a good start, but there are many other problematic areas with a Ljet, especially that gasket between the throttle body and intake plenum. Malcolm2 did a little write up with using a homemade smoke machine, which really beats using ether IMO. Also, since this car is new to you, consider adjusting the valves.

I once had to “blip” the throttle; check to see whether the throttle cable makes a smooth arc as it runs across the engine. I still lube the throttle body mechanism, after a rebuild it was stiff