Fuel Pump Experience - Buzzing Fixed

[TecNickal]

91 Grand Marquis wagon 5.0

Hey guys...
So on Wednesday I drove the car about 20 miles and stopped at a friends house. We were going to replace the exhaust manifolds, but unfortunately something happened when the car fired up.

The fuel pump has always been noisy in that car, made a loud buzzing. Carter fuel pump. So the car started, ran like crap, then died, all the while the pump went from making the loud buzz to a metallic shrill. Fuel pump on the way out...great...

So 2 nights ago, went to O'Reillys and picked up 2 fuel pumps - they didn't know which one worked in my wagon. Ended up being this was the one that works:

http://www.oreillyauto.com/site/c/detail/PFP0/E16138.oap?year=1990&make=Mercury&model=Grand%2BMarquis&vi=1199527&ck=Search_e16138_1199527_1617&keyword=+e16138

This past evening, After dropping the tank we noticed that on half the tank, the foam that should go between the body and the tank was gone. Metal on metal rubbing. So we used some 1/4" thick foam pads and glued them onto the tank.

After replacing the pump and reseating it, greasing up the gasket, we got the tank back up into the car (what a pain in the butt jostling the tank and filler neck, around the lines et all.

Restarted car after priming it. Would you believe the dang thing is nearly silent. So either the Precision fuel pump (made in USA!!!) is a quiet pump and/or replacing those pads got rid of the buzzing pump.

Besides the fact it dies on a hot restart unless you apply very light throttle (and it'll run like junk/misfire for a minute too)...it runs great. I replaced plugs 4-8 earlier this AM and replaced the IAC, so we'll see if that helps. Car runs fine at idle otherwise and while driving. Just a minor skip occasionally. We'll see if the plugs and IAC make any difference!

[VicCrownVic]

Restarted car after priming it. Would you believe the dang thing is nearly silent. So either the Precision fuel pump (made in USA!!!) is a quiet pump and/or replacing those pads got rid of the buzzing pump.

Probalby a bit of both, quieter pump and less vibration between the tank and body.

Besides the fact it dies on a hot restart unless you apply very light throttle (and it'll run like junk/misfire for a minute too)...it runs great. I replaced plugs 4-8 earlier this AM and replaced the IAC, so we'll see if that helps. Car runs fine at idle otherwise and while driving. Just a minor skip occasionally. We'll see if the plugs and IAC make any difference!

Did you clean the throttle body (and might as well hit the EGR while you're at it) when replacing the IAC?
Take a look at the picture in the first post of this thread: http://www.grandmarq.net/vb/showthre...-throttle-body

Mine would idle rough at a stop light when warm, cleaned up the IAC, TB, EGR and now it runs great.

[TecNickal]

Car runs great sitting at traffic light. Only problem is a hot restart. And issue is definitely still there. But plan is to clean the EGR and TB soon. Thanks for the link!!

The wagon completed the trip successfully. Won 3rd place in its class in a wagons only car show too, and I didn't do a thing to it! Its now been driven 3000 miles in the month that I've legally owned it. What a tank. It went up to Michigan...did a few hundred miles around there, before coming down to Indiana, did a hundred miles or so, then drove home. Never had to stop for anything but adding oil and gasoline.

It got 22-24 MPG w/the AC cranked to the max

[VicCrownVic]

I'm actually surprised that there haven't been some more useful posts here, there are a lot of people on this site that know way more than I do.

My 89 used to stall on hot restarts, but I don't remember what we did to fix it. It would start and run for about 1 second then stall when hot. May have been low coolant level, timing, bad temperature sensor?... I don't remember. It never ran rough like you described yours, all I had to do was start it again and it would start and run on the second try.

[TecNickal]

I have a some bad valve seals on cylinder head 1-4. You can see blue smoke out the passenger side pipe after its been idling. Driver side is clean. I imagine I have a fowled plug or two but gota take em out to look.

Luckily not my DD, so not a huge priority.

This was also a thread on fuel pump experience, so may not have attracted the regular audience - no big deal.

[packman]

I would start by checking your fuel pressure. See if it's within range; also see if it's erratic as well.

You may also want to replace the PCV valve and screen. It seems unrelated, but that will cause idling issues. I am currently having that problem due to a clogged PCV screen that won't budge (jammed into the intake). It will spray oil into the upper intake plenum at the throttle body. It will also oil up the IAC as well. I think the oil gums up the IAC plunger(s) and prevents it from opening all the way. That could be an issue.

Hot restart: I don't know how to check this, but that may be your starter; could be old or getting fairly toasty. Since you don't have headers, I don't think heat is an issue.

That's 1-1/2 cents.


Packman

[TecNickal]

PCV (motorcraft) and PCV screen and PCV grommet were replaced.

Car idles great once its going. Has a bit of a wandering idle after startup when cold.

Car starts fine on a hot restart (so starter is good luckily) - it's the runability of the car on a hot restart. It's missing.

Fuel pressure does need to be checked - to be done. And I'm changing the manifolds hopefully this weekend. Get rid of the leak. So I'll check plugs and FPR at the same time. Car definitely needs valve seals on bank of cylinders of 1-4. Sitting idle then stepping on gas gives blue smoke out the back. So I'll do both sides.

[Mainemantom]

I would start by checking your fuel pressure. See if it's within range; also see if it's erratic as well.

You may also want to replace the PCV valve and screen. It seems unrelated, but that will cause idling issues. I am currently having that problem due to a clogged PCV screen that won't budge (jammed into the intake). It will spray oil into the upper intake plenum at the throttle body. It will also oil up the IAC as well. I think the oil gums up the IAC plunger(s) and prevents it from opening all the way. That could be an issue.

Hot restart: I don't know how to check this, but that may be your starter; could be old or getting fairly toasty. Since you don't have headers, I don't think heat is an issue.

That's 1-1/2 cents.


Packman

If the PCV screen will not come out, use a long wood screw. Screw in, pull out. Worked well for me.

[sly]

If the PCV screen will not come out, use a long wood screw. Screw in, pull out. Worked well for me.

+1 I used a 3 inch sheetrock screw myself.

[bob5326]

+1 I used a 3 inch sheetrock screw myself.

Hello, I use long needle nose pliers. Open the needle nose up abit, and hammer them into the screen, tighten up the needle nose pliers, turn and pull......

[TecNickal]

Ugh. The car doesn't seem happy at all in hot weather when starting. It generally will start up, run for less than 20 seconds with a wandering idle, then what I think is stall…the idle drops and dies. All the while, the fuel pump is making a bunch of racket, like a shrill noise. Restart it again, same thing. Unless you apply just a touch of throttle for almost a minute until the fuel pump quits making noise, the car will stall. This is especially true after the engine has been heat soaked. This issue doesn't really appear during winter, only summer.

I have to wonder if it's the fuel pump again. I ordered an NOS Ford one specific to the Squire/Park just incase. I don't have much faith in the aftermarket ones.

[sly]

check the fuel pump relay.

[mobydick]

Ugh. The car doesn't seem happy at all in hot weather when starting. It generally will start up, run for less than 20 seconds with a wandering idle, then what I think is stall…the idle drops and dies. All the while, the fuel pump is making a bunch of racket, like a shrill noise. Restart it again, same thing. Unless you apply just a touch of throttle for almost a minute until the fuel pump quits making noise, the car will stall. This is especially true after the engine has been heat soaked. This issue doesn't really appear during winter, only summer.

I have to wonder if it's the fuel pump again. I ordered an NOS Ford one specific to the Squire/Park just incase. I don't have much faith in the aftermarket ones.

This sounds like a bad TFI module. Have you ever replaced yours? It's the small gray box on the side of the distributor. Aftermarket ones are known to be junk. I replaced mine on my 91 wagon. Ford part number DU2Z12A297A.

[mobydick]

Also have you checked your fuel pressure at idle as well as with the key on, engine off? Do it when it's cold and hot and make sure the pump is putting out adequate pressure. Check for trouble codes too. Just because the check engine light isn't coming on doesn't mean that there aren't codes being stored in the ECM.

[gadget73]

Have you ever metered out the coolant or air temperature sensors? Problems with cold or hot starts only are often a sensor that is bad or lying. DO a code scan if you haven't yet. It might tell you which is bad, but usually I've had to get out the voltmeter and test output vs what the temperature was to see if it matched up.