So I bought a Moats Quarterhorse for my 03 Mach 1 and installed it. No problems. I had the ECU out of the kick panel area and it was just hanging out. Everything was working fine. I put some electrical tape over the J3 port where the QH was poking out to seal it off so no moisture would get in there. Everything was still fine and I drove the car like that for about a day. I decided to put the ECU back in the kick panel. I was super careful with the ECU and the USB cable that was poking out the top. I got it mounted back in the factory spot and put everything back together.
This is where my problems start. I started the car and backed it out of the garage. The motor was running rough, check engine light on, wouldn't hold idle and actually died. I got it to start again and pulled it back into the garage. I removed the QH unit, tried it again and the car still ran poorly. I disconnected the battery and let it sit for 5 minutes. I came back and started it up. Car ran fine, no problems at all. Drove it around the block, it was fine. Parked it. Started it again a few minutes later. MIL came on within 30 seconds of the motor running but the car ran fine. I parked the car last week and havn't been driving it. Picked up a code reader this morning and pulled a P1451. According to this: http://www.obd-codes.com/trouble_codes/ford/p1451.php
It looks to be either the EVAP system or my ECU. I have tried to clear the code with my reader but it wont clear. I have checked fuses #2 and #8 under the dash and they are confirmed good with a DVMM. Now the car does have about 120,000 miles on it so the EVAP system could have a bad valve and if that is the only issue, I'll be happy but I don't think that is the case here.
Why would the EVAP valve cause my car to run like garbage from a cold start ? What I'm really worried about here is having a damaged ECU. The car does seem to run fine at the moment and I do want to be able to use my QH on it so I'm really stuck at the moment. Any help with the diagnosis would be much appreciated.
IT sounds like you may have an intermittent contact problem between your QH and ECU. Try a quality contact cleaner before running around and chasing ghosts.
I have completely removed the QH at this point. It is no longer attached to the ECU. I'm still seeing the code.
As for the contacts, I'm 100% certain they are clean. I spent 2 hours cleaning them with contact cleaner.
Edit/update:
I'm an idiot, code reader can actually clear the check engine. I was pressing the wrong button.
Alldata says to check the resistance at the EVAP solenoid but also says the solenoid is located where my FPDM is (out of date diagram). Is the solenoid on the EVAP valve on the later models ?
Hopefully you did not damage any wiring, I know it is a tight squeeze getting them back in once assembled. Best bet is to start testing stuff and find the issue. If all else fails a handy voltmeter will help alot.
Hmm..... damaged wiring.... that would actually explain everything. I was really gentle with the ECU but I guess it is possible I kinked it up and shorted something.... I'm going to start looking into it.
Edit/update:
Ok, so I pulled the front passenger wheel off of and went under the fender liner. I found the EVAP valve but this isn't what I was looking for as I don't have a way to teset it. I did some more research and found that the control solenoid for the EVAP system is on the canister which is located at the rear driver side just above the exhaust pipe, under the bumper. I was able to pull the electrical connector off the solenoid and test its resistence. Shop manual shows the proper range to be between 48-65 ohms. My unit clocked in at 58.7 ohms so I think it is not the culpret. I am going to put the car back together and take it around the block and see if the code manifests itself again....
In other fun news, I have a power steering fluid leak somewhere....
Edit/update:
After trying to put my ECU back in the kick panel area again and starting the car it ran like garbage again. I checked and I now had 2 codes. The same P1451 and a new P1233. I looked up P1233 and found this to be a FPDM issue. This is all starting to make sense to me. I must have a few wires that are shorting because when I giggle the wiring loom properly I get a car that runs fine. Looks like I will need to trace the harness and find the brake/short.....
Allright guys, I fixed it and I feel like a total dolt. One of the three wiring connectors that sit infront of the ECU had come loose. I went in there it inspect everything and while I was tracing the wires I went to pull a connector apart and it came right out like it wasn't latched. After reseating it, everything is working properly again....