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fuel issues/ module to module communication issues. bad PCM?
so ive been dealing with this issue for sometime now and it started with a P1235 engine code (open or grounded fuel pump primary circuit) so i ended up checking the ground for FPDM and replaced that module. after installing my car drove really well for 4 or 5 days and then it went to crap. Car would have trouble getting up to 60MPH it sounded like it was getting to much fuel and i could smell fuel. it would get worse the longer i drove it. i also noticed my theft light blinking really fast when car is off. sometimes it flickers fast, and other times its really fast, but does go away once car starts up. ive also got a P1260 code randomly (theft detected, vehicle immobilized) but car has never had issues starting. ive also had a U1262 data link fault code and a U1043 code (invalid or missing data for traction control) Ive also had a P0453 evap pressure control system high input pop up a few times, and ive seen a P1116 code pop up a few times. i never had a check engine light through any of this until last week whenever i replaced my belt & belt tensioner, now light comes on the dash. while its running i can hear a pop, sounds like a gas bbq pit when you press button to ignite the grill. ill here that every 20 or 30 seconds. i unfortunately have throw all parts at this and its got me nowhere besides more frustrated. ive gone from not knowing how to work on cars to fixing alot of things on mine and now trying to learn how to troublshoot electrical issues. ive got a multimeter and im getting familiar with using it but im lost at this point and all over the place and i need a good place to start. car does have a tune on it but it doesnt matter if tune is on or off the car the issues are the same. i apalogize for typing a book but this has been goin on for about a year so ive got sometime with this. im ready to actually find the problem and go back to a good running fun car. thanks for creating this website and helping us in need!!
yes i do have a check engine light on dash like i said after replacing belt and belt tensioner, my current codes are p1000 and a p0453 evap emission control system pressure sensor high input, and ive got 1 code on my hybrid electronic cluster which is a U1262 code system data link fault. and the way i checked my fuel pump ground was the wrong way i believe, i think i just checked to see how many volts it was getting and then just did a visual test to where its grounded at onto my car and everything was clean and making good contact. whats the correct way to test it though? i do have a topdon scanner so i can go through and see data in the different modules.
i should add whenever i go to the HEC where that U1262 code is thers a pcm verify on the live data and it says no as in pcm isnt verified. it said yes until after i replaced belt and tensioner
IMO, I'd start with chasing the P0453. Can't go wrong chasing current faults!
Key on engine off, at the fuel pump connector, you should have 5.0V on the brown/white, 0V on the grey/red and 2.5V on the red/pink. Red/pink is the fuel tank pressure signal wire, which the PCM is monitoring to set the P0453. Let us know what you find.
Sorry for the late reply been busy, but I just recently changed my fuel pump out and the new pump assembly connector that goes to my fuel tank pressure sensor is junk and I could never get it to fully connect, so after remembering that i dropped my tank last night and I’m just gonna de-pin the ford one that was originally on the car like I should have in the first place. I will do the volt test again once I get it back on the car. Unfortunately I’ve been having these issues way before that p0453 code.
I know there’s more to the popping sound I’m getting while car is running. I have no idea what it is but to me it sounds like a relay or something popping every 20 seconds or so. Driving me nuts
