Knowing the tow guy by name...

[Jesda]

So I was stranded in my Q for the third time in three weeks.

First time, the water pump belt went out due to a seized bearing.

Second time, which was last night, the fuel pump died. I got an original part from the dealer and had it installed, and it died again. There was no humming that would indicate impending failure, just suddenly it died. At least I hope thats what it was. The symptoms are the same.

Towed the car a mile from where it died to my mechanic. Does anyone think it could be something else?



-Jesda

[Q451990]

Fried fuel pump controller? MAF connecton?

Heath

[DAEDALUS]

Man, I hope it's not the controller. That's a $380 part!

[Q45tech]

Towing [or even a battery jump start] is the punishment for lack of PM and failure to bond one to one with the car.

Every one is allowed one of each in the cars life time [or the owners life time] but more than once indicates a defect in human or machine..............not learning lessons.

Guess I am being too harsh but a failed pump always gets a new controller at our shop..............or at least a 1 hour microscopic analysis of the controller and a warning that the stress may cause a imminent controller failure.

My controller is now on its 3rd pump [20k ago] and I just change the pumps when they FIRST get noisey from my selecting dirty gasoline............not the pumps fault.

[Jesda]

Well, I doubt the sky is falling, q45tech, but I think it could be a controller.

Typically, with regular maintenance on a vehicle and the use of quality gasoline, you dont suspect that parts like these will go bad. But the pump that came with the vehicle was bad, so it was replaced. But this controller issue is beyond what most consider "regular maintenance"

Bear in mind that the last pump on this vehicle was used. Who knows what further damage the last owner has caused by cutting corners.

Hopefully, my mechanic will discover that it was a defective part.

-Jesda

[Q45tech]

The FP controller is bullet proof unless YOU exceed the design current a lot for a short time or a little for a long time.

I must have a dozen in my junk box and T3 has replaced over 100 in 7.5 years along with 200 fuel pumps.

Old mechanical diaphram fuel pumps used to last 30,000 now electric ones last 70,000 miles or more.

"you dont suspect that parts like these will go bad."

Electronic speed controllers [fuel pump. HVAC fan motor, windshield wiper motor] all fail from the same cause - an overcurrent condition caused by a worn out motor.

I've been discussing this phenomenon for 4+ years on the WEB.

Failure to clean out the dirt in the tank is the cause of subsequent frequent pump replacements.

[Jesda]

So because controller failures are apparently caused by user error, would that not mean I should do fine with a used controller? $150 vs. $400?

Thx-Jesda

[Q45tech]

Used are fine if they work......the point is always use a new oem pump and clean the dirty gasoline and corrosion [from water] from the tank bottom.A controller will never take a pump out if all the 3 voltage modes are working as designed.

A full understanding of the failure mode will never leave you stranded plus understanding the emergency bypass method will get you another 25-50 miles of pump functioning if the pump DOES cause the controller to fail.

Previously I have described a wonderful 3 position switch addition/modification [normal, open circuit, and pump ground wire to chassis ground] which immobilizes the Q from common theft and provides emergency run to get a bad controller to the shop.

The reason I harp on this is we see so many tow ins for controller failure plus some don't follow the flat bed requirement and destroy transmission by towing with the drive wheels on the ground!

[Jesda]

I have a 2900-mile trip coming up in July. To ensure that I can make it the whole way, I guess I should not only change the pump and filter, (assuming a new controller is not needed) but also clean the tank.

My mechanic suggested that it is most likely a clogged filter. And the tow guy mentioned that some pumps have a reset switch?

-Jesda

[Jesda]

So what youre saying is, a dirty tank will cause a fuel pump to work too hard, which will then kill the pump and/or controller?

My dealer mentioned pump failure as being a common problem.

Thanks,-Jesda

[Jesda]

Went to the junkyard. They gave me the fuel controller module for free since they had no clue what it was. Installed it, along with a new fuel filter, and the total was only $85 from my mechanic.

Sure beats shelling out $400 at Scottsdale or $550 at Wendle Infiniti. I'm on the road again, thank goodness!

And the fuel tank was sparkling clean, too.

-Jesda