q45 fuel pump/control module
q45 fuel pump/control module
I have had my fuel pump/ control module replaced twice in the last 2.5 yrs/40,000 miles. Is this normal? and what woould be a reasonable cost for the procedure?
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elwesso
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2007 Infiniti G35 S 6MT - Location: Indiana
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The control module wont usually fail unless youve been driving around with a bad pump for a while........
<off the cuff> The control module is about 500, and the pump is like 200....... I dont know what labor would be, but it shouldnt be more than 2 hours.......
And...... The no1 reason fuel pumps fail is because of bad filters...... Its only a $10 part!!!
The Qs fuel pumps do fail, but they usually last quite a while......
<off the cuff> The control module is about 500, and the pump is like 200....... I dont know what labor would be, but it shouldnt be more than 2 hours.......
And...... The no1 reason fuel pumps fail is because of bad filters...... Its only a $10 part!!!
The Qs fuel pumps do fail, but they usually last quite a while......
Stick to a reliable clean gas station.Fuel pump: $315Fuel control module: $0-$50 at a junkyard. $100 on eBay. A used one is just as good as new, since its just electronics.Fuel filter: $8-$15
Replace all three at one time and you should be able to do 80k without a hitch. Also, Billman's B12 Chemtool ($3 bottle) is a good affordable way of cleaning crap out of the injectors and fuel lines. I paid $80 total for labor. Its one hour for the fuel pump, 10-15 minutes for the control module, and I dont recall for the fuel filter. No more than 15-25 minutes I would imagine.
-Jesda
Replace all three at one time and you should be able to do 80k without a hitch. Also, Billman's B12 Chemtool ($3 bottle) is a good affordable way of cleaning crap out of the injectors and fuel lines. I paid $80 total for labor. Its one hour for the fuel pump, 10-15 minutes for the control module, and I dont recall for the fuel filter. No more than 15-25 minutes I would imagine.
-Jesda
Fuel pump from http://www.infinitipartsusa.com (our friend) lists at $234.99 + shipping 'n handling
Q45tech wrote:Never had to change the fuel pump controller.........But I do keep a spare in the trunk along with the spare engine ecu.
I just change the fuel pump on my '90 Q. Without the benefit of an FSM I assume the controller is located above the tank attached to the rear deck? If so mine looked pretty good, no burned connections. The only thing that looked out of place was a yellowish substance which appeared to adhere a copper colored circular doohicky to the circuit board. Was this the controller?
> The only thing that looked out of > place was a yellowish substance> which appeared to adhere to a> copper colored circular doohicky
The biotech guys at the hospital I work for told me that yellow stuff is merely silicone vibration protection for the copper coil inductor on the FPCU PCB. That is apparently quite normal. It's in my FPCU also.
What you might wish to test is the resistance between the FPCU ground connector (the male pin labelled #4 on the printed circuit board) with any other solder point on that ground-wire trace on the PCB. Mine, for example, read infinite ohms until we re-soldered the fuel pump control unit connector pin #4 back to the PCB. (We added an additional jumper for insurance.) Now it reads 0.01 ohms from any point on that ground trace to any other point to pin #4 on the fuel pump control unit connector.
For debugging the FPCU, you _could_ follow the (tedious) suggestions in the FSM (which outline the use of a 4,5, & 6 wire connector created for a test jig between the white male fuel pump control unit connector and the white female fuel pump control unit harness connector) as per EF & EC-186).
Or, you could just follow q45tech expert advice which I accomplished by filing an alligator clip's teeth down (one side necessary only) so it just fits into the corner female terminal of the fuel pump control unit harness connector and then attach the other end of the alligator clip wire to any convenient ground. In my case, when the ignition was turned on, the fuel pump started humming for the first time in more than two weeks. The 16 AWG jumper wire I picked up from a friend in the lab does NOT get hot to the touch after a 20-mile ride in a mix of highway & local streets, so I assume the amperage to ground is low (electrical advice always welcome).
I am keeping the fuel tank full all week as I limp along with this workaround (as per fuel-pump cooling recommendations in this web site & at Yahoo). Funny. I haven't bought 2 or 3 dollars worth of gas so often since I was a teenager (a long time ago when fuel pumps were mechanical & bolted to the engine in my Dad's '67 Chrysler New Yorker 440 engine).
The critical secret, it seems, is to jumper the correct wire, which being fried in my case, revealed itself to be the lower left corner female terminal in the fuel pump control unit harness connector (facing the terminals with the tab at top).
The biotech guys at the hospital I work for told me that yellow stuff is merely silicone vibration protection for the copper coil inductor on the FPCU PCB. That is apparently quite normal. It's in my FPCU also.
What you might wish to test is the resistance between the FPCU ground connector (the male pin labelled #4 on the printed circuit board) with any other solder point on that ground-wire trace on the PCB. Mine, for example, read infinite ohms until we re-soldered the fuel pump control unit connector pin #4 back to the PCB. (We added an additional jumper for insurance.) Now it reads 0.01 ohms from any point on that ground trace to any other point to pin #4 on the fuel pump control unit connector.
For debugging the FPCU, you _could_ follow the (tedious) suggestions in the FSM (which outline the use of a 4,5, & 6 wire connector created for a test jig between the white male fuel pump control unit connector and the white female fuel pump control unit harness connector) as per EF & EC-186).
Or, you could just follow q45tech expert advice which I accomplished by filing an alligator clip's teeth down (one side necessary only) so it just fits into the corner female terminal of the fuel pump control unit harness connector and then attach the other end of the alligator clip wire to any convenient ground. In my case, when the ignition was turned on, the fuel pump started humming for the first time in more than two weeks. The 16 AWG jumper wire I picked up from a friend in the lab does NOT get hot to the touch after a 20-mile ride in a mix of highway & local streets, so I assume the amperage to ground is low (electrical advice always welcome).
I am keeping the fuel tank full all week as I limp along with this workaround (as per fuel-pump cooling recommendations in this web site & at Yahoo). Funny. I haven't bought 2 or 3 dollars worth of gas so often since I was a teenager (a long time ago when fuel pumps were mechanical & bolted to the engine in my Dad's '67 Chrysler New Yorker 440 engine).
The critical secret, it seems, is to jumper the correct wire, which being fried in my case, revealed itself to be the lower left corner female terminal in the fuel pump control unit harness connector (facing the terminals with the tab at top).
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Q451990
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tangalora wrote:> The only thing that looked out of > place was a yellowish substance> which appeared to adhere to a> copper colored circular doohicky
The biotech guys at the hospital I work for told me that yellow stuff is merely silicone vibration protection for the copper coil inductor on the FPCU PCB. That is apparently quite normal. It's in my FPCU also.
That's correct... you'll find it all over the Bose Amps on the coil too. I've looked at four FPCU now (two toast, two good) and they all have that.
The two toasted ones that I've seen had fried the four components that look like transistors (but aren't) that are anchored through the side of the case for heat transfer. I've been told that it's also common to have problems with the connection where the connector is soldered to the board.
Heath
P.S. Please tell me there's not really a place named "Fishkill NY"
I just now posted a complete summary of the process so the next Q45'er has an easier time collecting the data.
I posted my complete summary to:NICO Forums > Online Mechanic > Infiniti Online Mechanic > Fuel Pump Replacement
I still do not know how to post the revealing pictures of the entire step-by-step process, so, if you have any advice showing me where or how to send the photos (about 30) I'd much appreciate the information.
I posted my complete summary to:NICO Forums > Online Mechanic > Infiniti Online Mechanic > Fuel Pump Replacement
I still do not know how to post the revealing pictures of the entire step-by-step process, so, if you have any advice showing me where or how to send the photos (about 30) I'd much appreciate the information.
> The only thing that looked out of place> was a yellowish substance which > appeared to adhere to a copper colored > circular doohicky on the circuit board.
Attached, for clarification, is a photograph of the topside of my 1990 fuel pump control unit printed circuit board.
Notice the red arrow points to the so-called yellowish substance apparently stabilizing the copper coil inductor. This is apparently quite normal. (It feels like silicone gel.)
What is abnormal (and which can't be seen from this topside photo) is the #4 fuel pump control unit connector pin (circled in yellow) had apparently overheated and melted its solder connections to the underside of my FPCU PCB.
The fix was simply to vacuum pump the old solder out and resolder (attaching an ancilliary 14 AWG copper wire as additional current insurance).
Attached, for clarification, is a photograph of the topside of my 1990 fuel pump control unit printed circuit board.
Notice the red arrow points to the so-called yellowish substance apparently stabilizing the copper coil inductor. This is apparently quite normal. (It feels like silicone gel.)
What is abnormal (and which can't be seen from this topside photo) is the #4 fuel pump control unit connector pin (circled in yellow) had apparently overheated and melted its solder connections to the underside of my FPCU PCB.
The fix was simply to vacuum pump the old solder out and resolder (attaching an ancilliary 14 AWG copper wire as additional current insurance).
Here is a closeup of the topside inside of the 1990 Infiniti Q45 fuel pump control unit connector showing the burned #4 pin.
Despite it's scorched condition, this FPCU connector pin apparently is able to handle the ~6 amps drawn by the fuel pump through this path.
Nontheless, I added some additional copper (for insurance) to the underside of this 1990 FPCU PCB as was recommended by some of the posts here and at Yahoo.
Despite it's scorched condition, this FPCU connector pin apparently is able to handle the ~6 amps drawn by the fuel pump through this path.
Nontheless, I added some additional copper (for insurance) to the underside of this 1990 FPCU PCB as was recommended by some of the posts here and at Yahoo.
The most interesting & revealing parts are found when you peek at the underside of the FPCU PCB. Especially after you thoroughly suck out all the solder with a good hand pump (the blue tube in the photo).
Notice in the attached photograph my all-important #4 stud carrying juice from my hard-working fuel pump has slowly worked its way (probably via heat and incessant vibration) back and forth in its mating hole until there was no further connection to be made.
It's easy to see from this photo that an intermitent condition can easily result.
This is for the benefit of all you guys out there who have yet to relieve yourself of this condition.
Alora Duncan
Notice in the attached photograph my all-important #4 stud carrying juice from my hard-working fuel pump has slowly worked its way (probably via heat and incessant vibration) back and forth in its mating hole until there was no further connection to be made.
It's easy to see from this photo that an intermitent condition can easily result.
This is for the benefit of all you guys out there who have yet to relieve yourself of this condition.
Alora Duncan