Fuel pump problems

[Mr Whiskey]

My son just got an 85 gl10 wagon, ea82, mpfi, 2whl drive, auto.

We've put 3 fuel pumps on this in the past couple a days (two airtechs an a delphi) and a new fuel filter. Still have alot of noise comming from the pump. It hesitates badly (tries to stall out) when you first press down on the accelorator, then clears up and runs perfect, idles fine. The noise and near stall got me stumped (and worried, he's drivin it 60 mi.'s a day to work an back). This is my first experiance with a Soob but I was a mechanic way back when so I can do the work. Anybody could tell me what to look for next, I'd sure be greatful. I know I'm missing something simple.

I appoligse for just jumpin right in needin help (I am brand new here), but I just wanna try an help him get it runnin dependable.

I'll read the rules and fill out my bio directly, hope I haven't offended anybody.

The car's only got a little over 60k mi.'s on it and it did sit for a long time. Any advice y'all can give is appreciated, peace.

Edited December 15, 2009 by Mr Whiskey

[Holmes]

When was the last time it had a tune-up? Was the old pump dead or just

loud? They can be working fine and still be pretty loud.

[Gloyale]

Make sure the flapper in the Air Flow meter is moving smoothly.

 

Change spark plugs (wires too if you got $)

 

Replace cap and rotor.

 

Check the intake boot closely for any leaks.

 

Replace any hardened vacuum lines.

[The Dude Abides]

Make sure and use NGK plugs and wires. Beck-Arnley cap and rotor will work.

[Mr Whiskey]

Hasn't had a tune up in a long time (probably sat 3 yrs) and we're working our way to that. Old pump was working when parked but wouldnt when we went to get car. Replaced pump with Advance Autos Airtech and have been driving car but pump was VERY loud and tries to stall when you first try to pull out. Tried 2 Airtech's and then heard they were having trouble with them from manufacture. Installed a Delphi and problems are still the same.

I think it has to be a preasure or flow problem, only tries to stall when you first demand more fuel (step down on peddle) and it's hard to believe there would be so much noise coming from 3 different pumps. Something else is going on here. Almost sounds like there is fuel and AIR inside pump (sounds like a blender makin milkshakes). Noise changes pitch with rpm's. Runs and idles perfect other than these problems so it's hard to believe it's tune up related.

Read on here that mpfi has 2 fuel filters. If so I can't even find the one near tank, changed the one under hood. Is there anything else that would make it strain to pick up fuel? This pump is on the right rear, just in front of tire.

I quit working on cars about the time this thing was built and I've never worked on one of these so I'm kinda at a loss here.

You know how it is, daddy's tryin to come out lookin like his hero. Thank you all folks for your help, peace.

[Cougar]

Welcome to the forum here. Hopefully we can get this problem solved for you and your son.

 

The trouble may be with the fuel pressure regulator. You might try checking the flow to filter under the hood by disconnecting the input to the filter and see if you get good flow into can to catch the fuel. Be very careful if you do this as you can imagine the danger if fuel gets to the wrong place.

 

Another possible problem area may be with the throttle position sensor. It may have a dirty connection in it.

[Mr Whiskey]

Thanks for the welcome, and the help Cougar! Could you possibly tell me WHERE to find the TPS? I've got a pic of it from a parts site but the stuff I used to work on had carbs an chokes and I don't even know where to look for this critter.

So, here are the new things I know: Pulled fuel line from behind fuel filter, cranked car. Got GOOD flow, it will fill a half gallon bottle fast just crankin it over. No obstructions in fuel lines. Pump still whineing.

Pulled dist cap, button and cap supprisingly clean considering how long it sat. Look excellent to me.

Pulled plugs, gapped correctly and firing good and hot (cranked car with each individual plug in wire and grounded, she's firing fine).

Plugs are wet, I'm gettin fuel into cylinders.

Put finger into each plug hole (don't own a compression gauge right now) cranked car, seems to have good compression, pushes my finger out on each cylinder. (I've seen other stuff run fine with alot less compression.)

Now here's the kicker!! I did all this cause now the darn thing wont start!! It fired right up when we first went out there this morn, ran at 1600 rpms for about 90 sec's then just slowly dropped rpm's till it died. This is before I did anything to car, was just gonna set it up in the driveway better so we could get it on jack stands. All above was done in the hope of getting it started again. Wont even start with ether! Turns over fine, but wont start.

Sorry for the "book" I'm writin here but I'm simply outta ideas. Lookin for suggestions? Y'all help me find this "grimmlen" and I'll sure post what and how to fix it for others here.

Thanks for everything folks, this is a great site, glad I found it, peace.

Edited December 17, 2009 by Mr Whiskey

[wagonist]

EFI cars with the Black computer (-87.5) here had an issue with the earthing circuit for the fuel pump.

Power to the pump comes from a relay activated by the ECU, but the earth was back through the ECU itself.

This had a tendancy to burn out.

The syptoms on my car were at first occasional cutting out until one it stopped altogther (when my car was full of stuff as I was moving house, in peak hour, first morning in a new city:mad:).

 

Anyway, the fix is to simply run the earth wire of the pump directly to the car chassis.

Very simple to try.

 

Other problems I've had are clogged injectors. When were the last time they were serviced?

 

EFI cars have their standard filter in the engine bay. If a non genuine pump is being used, an additional filter may be installed between the tank & the pump to stop the pump being destroyed (the factory pump has a small screen mesh inserted into the inlet side of it).

 

TPS is a black box with some wires hanging off it to the LHS of the throttle body. On the early models this only had a idle switch & a full throttle switch so I doubt this is your problem.

Later models had a full potentiometer for the full throttle range.

[Mr Whiskey]

Thanks Wagonist, we'll try grounding the fuel pump directly in the morning. If that doesn't work then we'll try cleaning the contacts on the TPS. How would you go about cleaning the injectors? Appreciate the insite and tech info, we'll let ya know how it goes, peace.

[Cougar]

The TPS sensor is tied to the throttle cable and mounted on the throttle body like a carburator would be mounted.

 

Since you can't get the engine to fire remove the disty cap and make sure the rotor is turning when you try to start the engine. If it isn't turning you have a broken timing belt. Make sure spark is getting to the plugs. If you don't have spark then check for blown fuses. You may have a timing issue causing the trouble. A timing belt may have slipped.

 

As far as grounding the fuel pump wire I don't recommend you do that as it bypasses the safety system. If there is an accident you don't want fuel to keep coming out if the line gets severed. It sounds like there isn't a problem with that since you get good fuel output. The pressure regulator still could be bad though.

Edited December 17, 2009 by Cougar

[Mr Whiskey]

Thanks again Cougar! Yes I'm getting good fire to all 4 plugs. Checked all the fuses, they're all good. I think I can find the TPS now that you've told me where to look. We'll clean those electrical connections today.

Would it hurt to straight ground the fuel pump, just temporary, to see if it solves the problem? (I had a motorcycle wreck once and it caught fire, I sure wouldn't wanna see that happen in my Son's car.)

Could you describe the fuel pressure regulator, where to find it, any way to check it?

Suggestions on cleaning injectors? It might help me get it running again but I don't think it's gonna solve my noisy fuel pump issue.

Bless you Brother, cause this thing's drivin me bonkers, peace.

[eulogious]

Thanks again Cougar! Yes I'm getting good fire to all 4 plugs. Checked all the fuses, they're all good. I think I can find the TPS now that you've told me where to look. We'll clean those electrical connections today.

Would it hurt to straight ground the fuel pump, just temporary, to see if it solves the problem? (I had a motorcycle wreck once and it caught fire, I sure wouldn't wanna see that happen in my Son's car.)

Could you describe the fuel pressure regulator, where to find it, any way to check it?

Suggestions on cleaning injectors? It might help me get it running again but I don't think it's gonna solve my noisy fuel pump issue.

Bless you Brother, cause this thing's drivin me bonkers, peace.

 

I would straight ground the pump for diagnostic purposes, just make sure to "fix" it correctly if that solves the problem. Having a fuel pump not shutdown in an accident would be very bad.

[The Dude Abides]

Has cleaning the connections on the fuel pump quieted it down and not allowed the noise to come from the turn signals.

[Mr Whiskey]

I think you've got me confused with another post I saw on here Dude. I don't have any noise coming from the turn signals, it's comming directly from the fuel pump itself underneath the car. So loud you caint drown it out even with the radio.

I am gonna check and see if signals or break lights have any effect on "pitch" of noise like that post was talkin about, (assuming we can ever get it running again). I'll let ya know later tonight, peace.

[Cougar]

You stated that you good fuel getting to the filter and also the plugs are wet so fuel is getting to them. There still may be a pressure regulator problem that caused the original trouble. I think the regulator is near the throttle body area. Since starting fluid doesn't help get the engine running this is a bad sign. It sounds to me that the valve timing may be off somehow. I assume you didn't mess with the sparkplug wire positions. If the valve timing is off a compression check will show that up. As far as looking for an electrical problem as the cause of the pump noise I think you will be wasting your time.

 

You should purchase a service manual for the car. It is a great investment. You should be able to find the factory set of four manuals on Ebay for less than 50 dollars. Some of the best money you could spend on the car.

 

Here you go. Even though this set is for a 86 it will match your car pretty much. I suggest you get this set. Just the wiring manual alone is worth its weight in gold (well almost, at todays prices).

 

http://cgi.ebay.com/ebaymotors/1986-Subaru-Service-Manuals-3-Vols-FREE-SHIPPING_W0QQitemZ200417903404QQcmdZViewItemQQptZMotors_Automotive_Tools?hash=item2ea9d6832c

Edited December 17, 2009 by Cougar

[wagonist]

I had a quick look through a Chiltons manual in the state library (they weren't sold here) once & thought it wasn't bad.

 

Injector servicing needs to be done by a professional.

Removing them from the car yourself will save a lot in labour.

 

You need to unplug the loom from the injectors (a real bugger of a job), using a very fine screwdriver to "lever" the retaining clip out. These plugs will most likely be brittle from 20 years of engine heat, so be very careful.

 

Unscrew the clamps that secure the fuel rail to the injectors

Unscrew the injectors themselves (2 long, small bolts each)

find the bolts that hold the fuel rail down & undo these. Again be very careful, I think at least one of these is the bolt that holds down the inlet manifold. These bolt screw down into the water jacket in the head, so the end of the bolt gets rusty.

[rpholz]

was there gas in the tank when it sat?

 

my xt sat for 4 years before i got it and it ran horrible untill i dropped the tank and cleaned it. havent had a single issue yet.

[Mr Whiskey]

Okay, first off thanks again to all who are trying so hard to help us, we're learning (I think, haha).

Here's the days new info and progress: TPS connection looked fine, cleaned and dressed it anyway just to be on the safe side. Decided not to "hard" ground the fuel pump because if it was a bad ground it wouldn't have run in the first place, and we've got good flow. Tried to start car a couple of times, sounded like it wanted to run. Finally just cranked the p*** out of it while pumping the accelorator hard and fast. Got car running, on what sounded like 3 cyl. After it ran for about 3 min's it cleared and ran fine. Idle perfect. All four cyl's solid, I'm sure of it. Drove to parts store, (pump still whineing, car trying to stall again) and put injector cleaner in tank. Ran same, no noticable diff. Got home and had Son keep car running, started pulling plug wires. Both right (passenger) side plugs make no diff. It's running on the left two only. You can start, and keep, car running on only the left two cyls. Did not do this long. Can not get all four again at this time, sounds just like it did this morn when we first got it running, before it mysteriously cleared.

Pulled right side plugs and cranked car, got fire but looks yellow/orange not the good blue/white fire we had yesterday. Pulled right side injectors, reattached them to electrical and fuel rail with them out of the cylinders, cranked car, we're getting fuel. Changed right side plug wires, I had two jeep wires that worked, spark still looks weak to me.

? what would cause week spark on only the two right side plugs.

I don't believe it's a timing issue cause it's been so intermittant. If it was trying to jump time then it wouldn't suddenly run fine on all four. I'm trying to borrow a compression gauge to make certain but I still believe compression is good.

We're gaining on it! I'm sure the right side two are cuttin out, just don't know why. I hope one of you fine folks goes, "oh, that's easy, replace this" and tada!! Still thankful for technical info and best guesses all, peace.

[wagonist]

Yep, sounds like good fuel supply then.

 

Have you pulled the distributor cap off?

Starting to sound like corroded contacts in there as that's really the only part that sends spark to just one side.

 

I'd also swap the left & right spark plugs & see if the problem changes "sides"

[The Dude Abides]

Yea he pulled the cap and rotor off, said everything looked fine.

[robm]

Is the passenger side cam still turning? Maybe the passenger side cam belt broke?

[Mr Whiskey]

Well its rained all day ive not messed with it! but if it was the cam belt why would it have been cutting in and out(on two)? I've got fuel,fire,air, and comperssion!!!! The fire is the only thing i can find that changes(when it goes from four to two)! does anyone know if the pick up or the mudule under the distubor cap fires the motor one side at a time? im really thinking its something in that distubtor. its just too intermitting. if im just way off someone plz shout out!!!! THANKS FOR ANY AN ALL TIPS!

[Mr Whiskey]

Please forgive me, I expect I'm not doing this right, but as we get further into the diagnosis of this vehical I'm finding it necessary to start new post, as what I thought I knew changes.

Please don't hold it against us, my Son and I, we're new to this.

We appreciate all the valuable experiance here and are truly thankful for all who are tring to help. We hope you might read our newest post "No compression right front cyl/120 psi right rear " and continue to provide your insites and expertise. Thanks to all, peace.