My car will not idle when it is cold, after running for 5 to 10 mins ti will idle. The car also backfires when coming down from a high rpm. I believe it is a timing problem so I got out a timing light and hooked it up to the L1 wire and the timing mark was at the yellow mark on the pulley. So then I hooked the light to the T1 wire and it was also at the yellow mark. How do I correct this?

 

Forget the timing, adjust your TPS. Search for instructions. The yellow mark is supposed to be lined up with the pointer.

 

****also backfires when coming down from a high rpm***

Most possibly the anti afterburn valve in the acv is not working or the acv is disconnected or the airpump is disconnected or there is a air leak in the exaust.

***not idle when it is cold******

Most likely the fast idle cam/thermowax is out of adjustment or the thermowax is busted.

***So then I hooked the light to the T1 wire and it was also at the yellow mark. How do I correct this?***

Got me. Make sure the engine is fully warm when setting the timing.

Download the FSM's Fuel section at http://www.iluvmyrx7.com