Fuel pump

[96QQ45]

I hear the fuel pump humming loudly pre-start and can hear it softer during operation all the time. Is this normal or need to replace? Is it a difficult job to replace?

[PalmerWMD]

Not normal.Needs ot be replaced before it burns out the ( much more expesnive) fuel pump regulator.

Can be DIY'ed.

Fred...

[Rex]

While you await parts and time to get it done, keeping ther tank as full as possible can help prolong for a short period of time.

I'm sure I've read this on NICO, but can find it to reference

[maxnix]

As a matter of course, I always refill with a quarter tank left.

Be sure to replace your fuel filter also, and consider removing your tank and steam cleaning it for longer lasting fuel pumps.

[jtesensky]

Pump... $234.99 with o-ring, shipping, ground, about $7.00.here is a link: http://www.trademotion.com/par...id=55Just type in part number 17042-60U00, & select "Infiniti"

[tangalora]

Quote »I hear the fuel pump humming loudly pre-start and can hear it softer during operation all the time. Is this normal or need to replace? Is it a difficult job to replace?[/quote]If I can do it, anyone can so YES, it's a DIY job. You'll need the NICO ADVANTAGE, to get a head start, as the 1990 FSM merely lists what seems to be the wrong test instructions on page EF & EC-185 (most of which is unnecessary as q45tech's well-documented alligator-wire test is necessary & sufficient).

Unfortunately for you, I never got around to documenting the complete step-by-step (every step with a photo) fuel pump & fuel pump controller R&R&R (remove & repair & replace) but the details (in words) are ample, particularly in the following NICO Forums

• Online Mechanic > Infiniti Online Mechanic > q45 fuel pump/control module
• Online Mechanic > Infiniti Online Mechanic > feul pump control unit
• Online Mechanic > Infiniti Online Mechanic > problem after changing fuel pump
• Online Mechanic > Infiniti Online Mechanic > Installing Fuel Pump Control Module??
• Nico General > Infiniti General > Q45 fuel pump modulator
• Online Mechanic > Infiniti Online Mechanic > Fuel pump problem
• Nico General > Infiniti General > Fuel Pump Pictures
• Online Mechanic > Infiniti Online Mechanic > Fuel Pump Replacement
• etc.

About the only words I can still add to this extensive conversation is that nobody has pointed out in the NICO forums that BF-22 of the '90 FSM contains the all-important instructions for removal of the "rear parcel shelf finisher" & BF-43 of the 1990 Q45 FSM provides a diagram of the rear-seat removal process.

So, until I find the time to document what I've already photographed extensively (I shot hundreds of photos on this repair), you'll need to refer to the aformentioned threads.

Oh, and one thing I only learned in hindsight. If all you want to do is DIAGNOSE the problem, you can access all the key components from your Q45 trunk! In my opinion, THERE IS NO REASON TO REMOVE THE SEATS & PARCEL SHELF FOR DIAGNOSIS PURPOSES!

This might not be obvious from all the threads, most of which discuss R&R and diagnostic details.

In my opinion, the only reason you need to go thru the rear-seat & parcel-shelf is when you must REMOVE either the fuel pump or the fuel pump control module (that is, both removals require access from the rear seat).

Good luck. You can send me emails if you like, but I get so much spam that my mailbox fills daily so I delete most of it en masse every time I log in to yahoo. Better to append to the existing threads mentioned above (in the order listed).

[louiegz]

Someone like me, who is not that adventurous as you guys, need to get the fuel pump changed, how much should I expect to pay to have the dealer do it? Is this something that I could take to a regular mechanic to replace? I think my fuel pump is humming and I should get this checked out. For what I read, if it's an easy DIY, then a mechanic should be able to handle it. I dread to try it myself. Anytime I try to do something myself, I always screw it up.

[Rex]

DO NOT be afraid to do this yourself, the dealer (at least mine) said their policy is - pump, control module & tank removal .... $1300. I was able to do the pump (filter & O-ring) in a couple of hours, while cooking dinner at the saem time. I did not do a tank removal and cleaning as "inspection" of the tank showed no sediment (that I could see) and it wasn't really something I could do.

Good luck.

[Qdemption]

Don't dread this one louiegz. I just did mine today and it took under three hours. It is simple, not much to it at all. The hardest part was removing the seats and rear shelf. And that wasn't even that hard.

What I was suprised to find was that the tank itself was clean as a whistle. I was expecting sludge and all sorts of vermin in there. Didn't find a thing. Some more good news is that all the connections and fuel pump control unit was beautiful. Looked brand new. Good day for the Q.

[maxnix]

While sludge is certainly an indication fo the necessity of tank removal and cleaning, it is also the microscopic particles that coat it that do in the new fuel pump sooner than it should expire. Do a clean white cloth wipe on a dry tank and decide before foregoing the tank cleaning.

The color of the sock is a great clue.
Modified by maxnix at 9:08 AM 6/9/2008

[Qdemption]

I already sewed it up man. I am not going back in there. I would if that were the only project I had on the Q, but Ive still got two valve covers, a plenum, 5 bad injectors, and some brake pads to worry about and that is just what I have parts for.

The color of the sock was a brown, but not dark dark brown, just brown.

[Q451990]

Did you say 5 bad injectors?? I can't believe it runs on just 3 cylinders!

Heath

[Qdemption]

Yeah, 5 of 'em. The car has been parked now for 5 going on 6 months. Even when she was still running, I just don't know how 5 injectors could be bad and not notice anything. It leads me to believe that the harness is faulty too.

[tangalora]

I keep thinkin' of Johnny Cash' song: "I hear the pump a' humming, it's rollin' 'round the bend, I hear the pump 'a hummin', I don't know when" ...

I don't know what a 'plenum' is.Can someone describe what that is?Is it all the fuel hoses on top of the engine I see? (Sort of like an intake manifold, except for the fuel system?)

Also, folks keep talking about the valve covers with a problem. Can you edify me on that one also (I'd like to take a look at my plenum & valve covers to see if they have whatever problem it is that Q's get afflicted by.

[maxnix]

The plenum is the cast intake "spider". It's removal is necessitated by failing (10yr. old) hoses, certain injectors and knock sensors.

Valve covers leak, and for the early VH45DE, are sealed with a bead of silicon.__________________Brian1995 Q45 & Q45t & 2000 Q45


Modified by maxnix at 9:08 AM 6/9/2008

[tangalora]

Does that make the plenum the same as the intake manifold (that shiny silvery cast steel spider)?

[Qdemption]

Yup, thats it.

Doing the valve covers is more for inspection than anything. You can get out the sludge that is tucked in the crevices, and clean the actual valve cover, but other than that it is not too exciting. IMO.

ohh yeah, what maxnix said as well. If it leaks, then it might be a good idea to take a look at it.

[maxnix]

Does that make the plenum the same as the intake manifold (that shiny silvery cast steel spider)?

Please, it is cast aluminum alloy. We are not talking about Chevy's here.