Fuel pump stays running when key on engine off??

Charlie Allen

15 Year Member
Jan 7, 2008
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Normally, turn the key to on (engine not running) and the fuel pump will cycle, pressurize and then shut off. Every once in a while, it will turn on and stay on. When this happens, it turns on the CEL and runs very poorly and very rich. The code is 565, canister purge solenoid fault. This will only happen if the engine is ice cold, parked over night. I do not see how the fuel pump running and the CPS are related but that is the only code. Any ideas??
 
Possibly a sticking relay inside the CCRM. What happens if you were to say, remove power to the pump via the inertia switch, then reapply power? I'd be curious if it would release when the circuit is opened.
 
Wow... when i first went and put my car in the on position after its been sitting for about 2 years its doing the same thing... then u mentioning the cps... just made me realize mine isnt hooked up lol... i dont think it should make a difference but it sure has me wondering:rlaugh:
 
I don't see how they are related either. The CANP solenoid simply draws in gas fumes (held in the charcoal canister in the passenger fender) into the intake at partial throttle, much like how the EGR operates. There's no way you could have enough gas fumes to make the engine run rich.
 
Possibly a sticking relay inside the CCRM. What happens if you were to say, remove power to the pump via the inertia switch, then reapply power? I'd be curious if it would release when the circuit is opened.

I agree after futher investigation. I got it to do the same thing this morning, I unplugged the inertia switch and then reconnected the switch and the pump shut off and all back to normal. Do I have to spend the big bucks at Ford for a CCRM of are the available aftermarket?? Ford # F48F-12B577-AA
 
I don't have a wiring diagram handy right now, since I'm at work, but I bet you could find which wires it is and wire one in separate from the CCRM. Autozone tends to have some decent diagrams on their site, but they changed it around and require you to register now before you can view them.
 
When this occurs, CCRM Pin 18 should be dead after the prime-out period. Check yours to see if it shows continuity to ground when the pump is running on. If so, it's an EEC or wiring issue, not the CCRM.

If 18 is cold, check CCRM Pin 5 for 12V. It should not be there after the prime-out (this is the output from the CCRM to the FP). If 18 is cold but 5 is hot, the relay is probably latched, as suggested.
 
Thanks Hissin, as usual, your replies are very informative. I was prepared to use your test method today it refused to malfunction. I bet I did a key on, key off 100 times and all was normal today. Will try again tomorrow and hope it will be in a "broken? mode to prove my issue. Thanks much.
 
When this occurs, CCRM Pin 18 should be dead after the prime-out period. Check yours to see if it shows continuity to ground when the pump is running on. If so, it's an EEC or wiring issue, not the CCRM.

If 18 is cold, check CCRM Pin 5 for 12V. It should not be there after the prime-out (this is the output from the CCRM to the FP). If 18 is cold but 5 is hot, the relay is probably latched, as suggested.

Hissin
Thanks much for the road map. Via the recipe you have described, the ECM is at fault. First question, is there any performance difference between a 48 states unit and a California ECM?? I am using a Tweecer. Question 2, I have heard the reman units are not the best and I would better off with a used unit from a donor car. Any truth to this in your experience?? Question 3, do you know of any suppliers for used units?? The wrecking yards in Los Angeles seem to be fresh out of these. Automatic car CBAZ U4PO
Thanks again
 
What happened? Was 18 staying grounded? There's actually a ground port for this circuit in the self-test connector (it's there so you can do diagnostics without having to constantly cycle the key to get the pump to come on). So make sure there are not wires tapped or shorted wires in the self-test-connector area.

If that's the only issue, I'd not sweat it really. If this always happens with the other issues (running poorly, rich, etc), then I like the idea of trying a spare EEC.

I'm not a Tweecer guy. Is there any way the connection on the J3 port or the unit itself can cause an issue like this (I think I remember some people having issues with the switch)?

You don't happen to have a friend with a spare EEC do you? This is an educated guess but we don't know for sure that the EEC is the issue. It'd be nice to test the theory with a minimum or no cost.

Since you have the RT, you can use any CBAZA EEC. You can score a U4/W4 for cheap and then use your TwEECer to 'make it a stick trans.' For the same reason, the 49 state vs Cali EEC should not matter. I don't know how the Cali EEC is different in terms of the tune.

If the reman'd EEC has a lifetime warranty, that would not be bad. AFAIK, they test OEM puters and if they test ok, they sell them. They might also make slight repairs (burned caps, burned traces, etc). I still like using an unmolested OEM puter from a donor. The Corral classifieds or ebay might have something.

Who's in LA? Chythar is IIRC. With all the swap work he's done lately, he might know of some yards off the beaten path that might have an EEC.

Good luck.
 
California, eh? I have a GT Auto computer that I don't need anymore. I have not used it myself, so I don't know if it is good but it's worth a try. I am in West LA; if we can meet up I'm willing to lend the PCM to you as a test. If it works, I'll sell it to you cheap. PM me and we'll find a time & place to meet.

There is no difference on our cars for Federal and California emissions - ALL the parts are 100% identical. Ford just didn't pay the extra to certify all Mustangs in California.
 
Charlie stopped by tonight, lent him my spare W4H0 computer. He's a great guy, we had a good chat abvout our various Mustang projects. He's gonna try out the W4H0 for a couple of days, see if this PCM solves his fuel pump problem.
 
Ok, here is the latest... plugged in the ECM that Matt was so kind to loan me and cycled the key on off about 30 times. Fuel pump primed and shut off each time. Started the engine about 5 times, all still well. Plugged in my Tweecer and rewrote my tune, cycled the key about a dozen times, all still ok. The pump seems to function correctly. I will try all of this again tomorrow and keep my fingers crossed. Many thanks to Matt for being a gentleman and so helpful.