Fuel pump keeps priming

[Screamin_dutch]

2005 GT

Changed my filter and pump today to battle the hesitation TSB problems.

Opted for a Bosch replacement for 2007 and up GT's, from Rockauto.

Install went fine, removed #21 relay and cranked couple times to relieve pressure. Put everything back together and it starts, runs and drives fine.

Only weird issue is, with the key ON, the pumps keeps priming (loud) and never stops. Plugged and unplugged the relay couple times but it keeps doing it.

Any ideas?

 

[sman247]

Do you have an AFR gauge to make sure your not leaning out and its running right?

 

[Screamin_dutch]

No, dont have a handheld either. Pretty much bone stock car engine wise.

Just switched the relay with the ac clutch relay as they were the same, and it still keeps priming so that rules out the fp relay.

 

[Screamin_dutch]

Update: even got a CEL. Sadly no code reader.

Reset everything, pulled the pump and checked everything. Put it back, still keeps priming.

Put the old pump back, no problem. Primes twice for 1 or 2 seconds and done.

So either this pump is faulty from the factory, or there is indeed a difference between 05 and 07+ pumps because I ordered a 07+ (bosch 66063) after people told me there was no difference through the years.

 

[sman247]

Im not sure if there's a difference but that sounds faulty to me.

 

[sman247]

So doing some quick research it looks like the 05 one is different than the 06-09. Looking on lmr.com they have the 05 fuel pumps listed separately from the 06-09 with the exception of the dual fuel pump kit. So chances are its not working because its not for your year

 

[Screamin_dutch]

I know, but most people on here agreed they were interchangable. Even Ford, in there own TSB said to swap the 05 pump for a partnumber that is their 06+ motorcraft one.

Anyhoo, I ordered another 05 bosch pump. Hope it gets here before I leave for Le Mans.

 

[sman247]

Hope it works out

 

[Pentalab]

When I had my pump out.... to clean the sock over the bottom of the pump assy, once all cleaned, and back in, we used the following priming method. Turn key to 'on' position ( for 2-3 secs max)....and we hear the pump priming, then key to 'off'. Then repeat process, with key on/off... a few times, till we don't hear the pump priming anymore. Then turn eng on...done. This is on my 2010 ( 4.6 / 3V )..with oem 2010 pump.

 

[redfirepearlgt]

Can't do much without a scan tool of some nature, and suggesting to drive it to a parts store to finf out what the problem is would not be advised if the car is running lean (likely is).

Recheck the connection to the Fuel Pump Demand Module. If the connections have not been compromised, then recheck your fuel line connections. Sounds like you have a faulty fuel pump or you have blow by in the tank which is not allowing fuel pressure to be made either way at the Fuel Rail Pressure Sensor at the engine. Key off and on several times as mentioned above is one method to priming the system.

When it comes to fuel pump replacement I have taken the advise of others who have learned from their mistake of going aftermarket and always gone OEM. That is with respect to a stock returnless configuration.

 

[Screamin_dutch]

I could prime for a few seconds all I want, had the pump out twice and it was installed correctly. It would keep priming nomatter what I did. Car ran fine anyway.

I would agree I did something wrong or something is wrong with the car, if the old stock pump had the same issue. But after putting the old stocker back, everything was fine. Primed twice for a few seconds and stayed quiet the 3rd time I toggled the key to ON.

Rockauto won't take my pump back because I ordered the 07 pump knowingly for my 05, and Bosch sells a seperate 05 pump.

 

[redfirepearlgt]

I could prime for a few seconds all I want, had the pump out twice and it was installed correctly. It would keep priming nomatter what I did. Car ran fine anyway.

I would agree I did something wrong or something is wrong with the car, if the old stock pump had the same issue. But after putting the old stocker back, everything was fine. Primed twice for a few seconds and stayed quiet the 3rd time I toggled the key to ON.

Rockauto won't take my pump back because I ordered the 07 pump knowingly for my 05, and Bosch sells a seperate 05 pump.

Undoing what you did is a good TS concept. Many are to proud to undo something back to the way they found it to see if A.) the new device is bad or non compatible, or B.) something got wired wrong...or a step was missed.

How many miles are on the car? Just curious. The pump on my 99 F150 failed with about 60,000 miles on it, but it was also roughly 14 years old at that time as well. I went with all Ford OEM on that job, and of course, the tank was full when it crapped out.

 

[Screamin_dutch]

I luckily ran it to a 1/4 tank because I knew I was going to change it.

It has a 2004 sticker on the pump, car has 55000 miles. The pump is still working fine, just has the hesitation problem sometimes. I wanted to change it as preventative maintenance.

 

[redfirepearlgt]

Best way to start isolating anything with regard to a "hesitation" IMHO would be to do some datalogging. Best of luck to you.

 

[justin73]

I had a 92 5.0 foxbody that did that called ford service manager I know and he told me the computer or ecm was fried. So took computer out and put new one in and it fixed the problem. Never had problem again.


Sent from my iPad using Tapatalk

 

[Screamin_dutch]

I read a lot of foxbodys had this issue, but if my ecu was toast, I wouldnt be driving it all fine and dandy with my old pump now..

New bosch 2005 pump get here tomorrow, lets see if that works.

 

[Screamin_dutch]

I'm losing it, new bosch pump for 2005MY keeps priming too. Wtf

 

[redfirepearlgt]

At this point until you monitor fuel line pressure, you aren't going to know what is causing the problem from where I sit. The Sensor on the Fuel rail reports to the PCM to tell the FPDM to stop running the Pump at key on/engine off until either the time out occurs or proper pressure minimum is seen at the fuel rail. Until you this is known, it would be difficult to move on.

Key on engine off pressure setpoint on the fuel rail is 30-50 psi. 3 seconds is the standard time the manual states for the system to reach pressure at keyon engine off. It does state that several key cycles may be required to reach proper pressure after replacing the fuel pump or associated lines after bleeding the system.

Can't help you any further as I believe the problem is with the device you are receiving. Either it is undersized, faulty, or otherwise I do not know, but the only way to find out for sure is to obtain OEM and try that.

 

[Screamin_dutch]

PROBLEM SOLVED!!!!

Thanks to this youtube video

Pumps arent faulty, nor the model year matters.

Bosch, and others, in their infinite wisdom decided to add an extra permanent ground to the pump motor. So its at full blast all the time. Why? Its beyond me.

Snipped the ground, put the 07 one in and all is well.

Ps, it threw code P0191 before

 

[Screamin_dutch]

Picture of said ground. Snip the one going to the spring/leg.