nsyr

86 951 all stock. When the engine is cold it just doesn't want to run right. I give it gas with little response. Once the engine warms up it runs fine. I just replaced the oxygen sensor do to bad gas milage. Any ideas?

Bri Bro

Temperature sensor that goes to the DME, not the one for the gauge.

DrZ1

MY 86 had a similar problem until I changed Mass air meter to known good one.

Steve

LFA951

These cars always run crappy when cold, let her reach her normal operating temperature and you'll see the difference.

Spidey944

I start mine in the AM while getting ready for 5 minutes b4 driving. Everytime. Much easier on the engine/turbo components.

Ski

Both likely causes already mentioned, but if this just started all of a sudden, check the TPS as well.
tip - http://www.arnnworx.com/tps-repair.htm gives some good points on testing.

BlacknRedGT

you know whats funny... I had to literally give my car gas for 2 min before driving off. I removed the heater control valve and now I just have to give it about 5-10 secs of gas before going.

turbo8

isv?

billthe3

My car is completely gutless until it warms up. I always slow down traffic when pulling out on a right turn because I don't want to push it hard enough to accelerate at a decent rate.

Bri Bro

Good point, there is a thermister inside the air box that measure the air temp. Both the engine and air box thermisters can be checked with a meter with little effort.

RKD in OKC

My 951s have always ran great when it is cold. 15 psi becomes 16 psi with no other changes.

Oh, and I think letting a car idle for anything more than 1 minute before driving is just a waste of time. The only thing you are warming up is the motor itself and there are so many other things that need warming up to operate at best. In the boxster manual it actually states to NOT let the car sit at idle to warm up. That you should instead drive the car easy for a few minutes before driving aggressively.

Rock

Yeah. The BMW manual for my 735I says do not let the car idle to warm the engine. It also says drive the car lightly to let it warm up

azmi951

just a cold motor. let it warm up.

hosrom_951

Runs great cold & warm......................

Check the sensors mentioned above.

Enothe

mine was doing this too. it turned out that the refernce and speed sensor harness wires going to the DME were falling apart. i respliced that area and it fixed it.
try that or the DME engine temp sensor