Yes. The main picture is the AC switch connection, but it’s likely related. Previously, I thought I’d resolved the annoying misfire/stumble/stall issue with some good, old fashioned battery maintenance, but with the temperatures beginning to rise again here in Phoenix, the issue has reared it’s ugly head once again.
When the car is at operating temperature, it will begin to misfire so erratically, the ECU can’t keep pace and it stalls. Almost entirely random, the only consistency I can come up with has to do with the ambient air temperature being above 70*F and the coolant temp being soundly into normal operating temperature.
- Could it be the CLT (coolant temp sensor)? A/F is calculated based on airflow and coolant temperature. If the CLT signal is dropping out, the ECU could be getting mixed signals, jumping between 190*F and -40*F, for example. Fuel delivery goes crazy, the lean/rich pendulum sways wildly back and forth, before flooding out.
- Could it be the fuel pump getting old? I’ve heard of high mileage fuel pumps getting hot and flaking out, but it’s definitely not dependent upon fuel level – the issue happens on both nearly empty and nearly full tanks.
So, because I was out in the garage the other evening tinkering while waiting for a phone call from a Canadian rally driver (Gearbox interview), I decided to chop out and replace the obviously worn out AC switch connection. That clearly hardened bit of wire harness is also what connects the CLT to the ECU, so it’s still a prime culprit.
Here’s a couple more shots. It was a quick-n-dirty repair. I’ve got a properly done up piece to go in shortly, but I wanted to see if this had any affect on the issue – it didn’t.
