Rich misfire when cold? S5 N/A
 

So my car has been getting crappy fuel mileage lately. Hasn't been running too shit hot either which I'm sure is related. It runs fine when it's warm. But whens it's cold, and not under load it misses. I'm pretty sure it's a rich misfire, not lean, because it really stings the eyes and nose. It won't miss if it's under load, but will just free revving. I took a video to show you guys what I mean. This was a cold start at the shop this morning:

http://www.youtube.com/watch?v=vyY46B245mo

It's really hard to hear it on the vid but it's running like bwaaaaaaaaaaaa put bwaaaaaaaaaaaaaaaaaaaaaaaaa put bwaaaaaaaaa put bwaaaaaaaa put..... etc


I recently replaced the coolant temp sensor and 02 sensor less than 1000 kms ago. The plugs/wires/fuel filter all have less than 15k on them. When I pulled the plugs they had alot of carbon on them- which again leads me to believe that I'm running too rich. The motor has only 35000 k on it. Grounds are good. The MAF has been tested and is good.

The ONLY thing I can find that is out of spec is the TPS. So I tried to set it up using the test connector. I just used a couple of multimeters rather than led's, but it's the same thing. When I got it to the point where one was 12v and the other was 0v, and tried to drive it, the car ran like crap and had no power. So I tried to set it up using the multimeters to check resistance on the sensors, and couldn't get the resistances within specification.

So I guess my question would be:

1. Could the TPS be causing this whole issue of crappy running and bad fuel mileage (13 mpg mixed- I used to get 19 mpg)

2. Anything else that could cause this?

bump..... trying to sell the car, need this fixed asap

back to page 1

After you start the car and it rev's up, give the throttle a tap and it should drop the rpms down to 2k. As far as the braaaaaaaaaa brap braaaaaaaaaaaaaa noise, i havent owned an rx7 that didnt do that when it was cold.

I know that. It does that fine. And as it warms up it slowly drops down to 900 RPM when fully warm. That's not my problem. It's the miss that is.... and I think it's related to my crappy mileage

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