Clogged fuel pressure regulator (with pics)

AUFanboy · 09-09-2012, 11:47 PM

While playing around with my scan tool I noticed my car's (AU I6) fuel trims were very negative at idle and overrun, around -15 to -30%. This means ECU is cutting back on fuel in response to a rich condition. Generally this indicates leaking injectors, excess fuel pressure or a regulator leaking fuel through the vacuum line. I did some googling and found that AU Falcons have an issue with the fuel rail rusting internally and plugging up the regulator, leading to excess fuel pressure because the regulator is on the outlet end of the rail (it bleeds the surplus fuel back to the tank to control pressure). Decided to pop the regulator out for a look and here's what I found:

http://fordforums.com.au/attachment....1&d=1347197294

That's supposed to be a clean filter screen! Proper fix is a new regulator and fuel rail, but I decided to just clean the screen and re-install for now. After cleaning with a cloth and a can of WD-40 it looked much better:

http://fordforums.com.au/attachment....1&d=1347197294

Re-installed and went for a drive. Fuel trims are now back down in the 0 to -10% range and the car is idling better, so it seems to be fixed for now

Probably worth a look if your car is running rough/rich and you've already tried new plugs/leads etc. Here's how to remove the little b@#$%^#$:

1 Remove fuel pump relay and crank engine to bleed off any pressure.
2 Remove vacuum line then remove the circlip that holds the regulator in its seat - circlip pliers help here.
3 Attempt and fail to pull the regulator out by hand.
4 Use vicegrips wrapped in cloth to twist, wriggle, and pull on the regulator.
5 Curse and swear because it's not coming out and the vice grips are just slipping.
6 Get rid of the cloth and just chew up the regulator casing with the vice grips, with enough force it will pop out (o-rings are a very tight fit).
7 Clean or buy new regulator.
8 Try to push the reg back in by hand, fail and swear some more.
9 Tap it back in with a rubber mallet, socket extension bar, and cloth.
10 Reinstall circlip and vacuum line.
11 Before starting engine jump fuel pump relay with a wire to run the pump and check for leaks.

AUFanboy · 09-09-2012, 11:53 PM

Of course, you could just check the fuel pressure before bothering to pull the regulator out. But since Ford didn't put a schrader valve on the fuel rail checking the pressure is a pain too...

Maka · 10-09-2012, 08:28 AM

Timely post AUFanboy, have to do this on mine. Thanks for the writeup makes it alot easier.
Quick question- do duel fuel rails differ from petrol fuel rails? Ive got a spare and the fuel pressure reg is different (no circlip holding to rail, 2 bolts only)
Anyone know?

cheers,Maka

**auIILTD** · 10-09-2012, 10:52 AM

Has this pulled your STFTs back into line?

mik · 10-09-2012, 12:47 PM

Quote:

Originally Posted by AUFanboy

Of course, you could just check the fuel pressure before bothering to pull the regulator out. But since Ford didn't put a schrader valve on the fuel rail checking the pressure is a pain too...

unless you have fitted a t piece and run a hose to a fuel pressure gauge on the fire wall ;).

Maka · 10-09-2012, 04:21 PM

Quote:

Originally Posted by Maka

Timely post AUFanboy, have to do this on mine. Thanks for the writeup makes it alot easier.
Quick question- do duel fuel rails differ from petrol fuel rails? Ive got a spare and the fuel pressure reg is different (no circlip holding to rail, 2 bolts only) Anyone know?

cheers,Maka

Just found the answer, the spare i have is off a ef-el doh!

cheers,Maka

**Papa Smurf** · 10-09-2012, 04:27 PM

Quote:

Originally Posted by AUFanboy

Probably worth a look if your car is running rough/rich and you've already tried new plugs/leads etc. Here's how to remove the little b@#$%^#$:

1 Remove fuel pump relay and crank engine to bleed off any pressure.
2 Remove vacuum line then remove the circlip that holds the regulator in its seat - circlip pliers help here.
3 Attempt and fail to pull the regulator out by hand.
4 Use vicegrips wrapped in cloth to twist, wriggle, and pull on the regulator.
5 Curse and swear because it's not coming out and the vice grips are just slipping.
6 Get rid of the cloth and just chew up the regulator casing with the vice grips, with enough force it will pop out (o-rings are a very tight fit).
7 Clean or buy new regulator.
8 Try to push the reg back in by hand, fail and swear some more.
9 Tap it back in with a rubber mallet, socket extension bar, and cloth.
10 Reinstall circlip and vacuum line.
11 Before starting engine jump fuel pump relay with a wire to run the pump and check for leaks.

I recently had the same trouble and did pretty much what you had to fix it. I removed the Fuel rail and cleaned it our thoroughly with thinners and later some wonderful Stove cleaner then some more thinners. I changed the Fuel filter as well, seems to have fixed the problem.

AUFanboy · 10-09-2012, 11:59 PM

Quote:

Originally Posted by Papa Smurf

I recently had the same trouble and did pretty much what you had to fix it. I removed the Fuel rail and cleaned it our thoroughly with thinners and later some wonderful Stove cleaner then some more thinners. I changed the Fuel filter as well, seems to have fixed the problem.

Good idea to pull the fuel rail and clean. I'm hoping that most of the bits that were gonna flake off had already flaked off and found their way to the regulator... don't understand why they are rusting internally though, must just be made of crappy steel. Did much more crud come out with the thinners?

@auIILTD: yep the fuel trims are back in line. At idle I'm now getting LTFT around -2% and STFT bouncing from -3 to 3 or so in closed loop mode. Before cleaning i was getting LTFT pegged at -19.9% on idle and STFT around -10%. It then gradually crept back to around -15% (combined) after an hour or so of driving - I think this happened because the fuel was gradually warming up and passing through the plugged reg more easily.

**Papa Smurf** · 11-09-2012, 12:46 AM

The reason is that they are made of steel. BA's had the same trouble and Ford would NOT replace under warranty as they claim it was the fault of the Fuel.
The BF Falcon came out with a Stainless Steel one, no more problems.

I did get a lot of rubbish out of it with the thinners and oven cleaner plus I was able to get a flexible brush through it. Am a Happy Camper now.

Maka · 11-09-2012, 08:57 AM

It would be nice if that stainless steel BF Falcon fuel rail fitted the AU Falcon.

cheers,Maka

AUFanboy · 29-09-2012, 02:59 PM

Update to this... the fuel trims are still good so the regulator cleaning seems to have worked fine. But the car still has a vibration at idle, enough to shake the side mirrors slightly and get anoying when sitting at the lights. No obvious missfires and it runs fine once moving/under load, just the idle is a bit uneven. Engine compression is good (170 psi +/- 5), plugs/leads are newish and I've checked for vacuum leaks and replaced the intake manifold gasket and PCV valve (made no difference but good to have done anyway). I'm 99% sure it's not ignition related because problems there show up under load first. So I'm thinking I should just bite the bullet and pull the fuel rail, clean it out, and fit reconditioned injectors. Given how much crap was in the regulator it's likely the injectors are filthy too and causing the uneven idle.

Any tips on removing the rail? Looks like there are some "quick" connectors under the car, do I need a special tool to undo these, or just can I just push back the internal clips with a small screwdriver (like the ones on the filter and pump).

scottichaos · 14-10-2012, 09:43 PM

i changed my fuel rail to one off a ef to make it easier to remove the reg.(2bolts)

AutoTX5 · 14-11-2012, 08:57 PM

My dual fuel AU '99 runs well on LPG or petrol, but the exhaust really, really stinks when running on petrol. Stop at the lights and if the driver's window is open the exhaust smell comes in or when engine running and unloading from the boot the smell almost knocks you out.

Plugs are sooty and high tension leads are new as well as fuel filter near the rear wheel arch. O2 sensor replaced about 8 months ago. AU has about 136,000 Km.

Do I look at changing the regulator and injectors? I don't know if the ECU will give codes for this model. What is the cheapest reader for this?

FERG_51 · 15-11-2012, 12:10 AM

Quote:

Originally Posted by AutoTX5

My dual fuel AU '99 runs well on LPG or petrol, but the exhaust really, really stinks when running on petrol. Stop at the lights and if the driver's window is open the exhaust smell comes in or when engine running and unloading from the boot the smell almost knocks you out.

Plugs are sooty and high tension leads are new as well as fuel filter near the rear wheel arch. O2 sensor replaced about 8 months ago. AU has about 136,000 Km.

Do I look at changing the regulator and injectors? I don't know if the ECU will give codes for this model. What is the cheapest reader for this?

Get a fuel pressure test, if high i would be cleaning rail and regulator.

Sox · 22-09-2013, 09:41 PM

Bit of a thread mine here, but I spotted this thread being mentioned from another thread.

Anyhow, why is a screen needed at this point considering it's on the outlet end of the fuel rail?

I ditched the filter from the reg ages ago for this very reason, and things have been fine since.

Maka · 23-09-2013, 10:37 AM

Quote:

Originally Posted by Sox

Anyhow, why is a screen needed at this point considering it's on the outlet end of the fuel rail?

Good question, a blockage in the fpr will negatively affect fuel pressure (high) so the screen is there to not circulate any crap out of the fuel rail (rust, corrosion) when fuel is returned back to the tank, its meant to be cleaned when a blockage is suspected (otherwise it would be a sealed unit, replace when blocked).

"Fuel pressure regulator failure due to contamination from accumulated fuel rail debris causing excessive fuel pressure." (from AFI diagnostics)

With you removing that gauze, your fuel pump filter is also now your fpr filter too lol!

cheers, Maka

Sox · 23-09-2013, 10:59 AM

Quote:

Originally Posted by Maka

Good question, a blockage in the fpr will negatively affect fuel pressure (high) so the screen is there to not circulate any crap out of the fuel rail (rust, corrosion) when fuel is returned back to the tank, its meant to be cleaned when a blockage is suspected (otherwise it would be a sealed unit, replace when blocked).

"Fuel pressure regulator failure due to contamination from accumulated fuel rail debris causing excessive fuel pressure." (from AFI diagnostics)

With you removing that gauze, your fuel pump filter is also now your fpr filter too lol!

cheers, Maka

It was more of a rhetorical question.

What I was getting at is how likely is it that these FPR's will have a problem from the tiny amounts of debris? My guess is none.

I'd bet any debris from the fuel rail will pass straight through the FPR and back to the tank like you said. The amount of debris is so small to be of no consequence in the tank sloshing around because firstly, the gauze on the pump is huge by comparison, and secondly, they are self cleaning to a point as the debris is in constant motion.

I've seen FPR's in for hundreds of thousands of k's with bugger all debris anyhow.

Maka · 23-09-2013, 11:40 AM

Ah, i get what your saying now! All i can say is AFI has obviously seen some bad examples as to release a service bulletin, would long term users of e10 for example suffer from fuel rail rusting eventually?

In the OP, Fanboi found debris in his fpr & it was blocked enough to affect his fuel trims -in his 3rd post - "Given how much crap was in the regulator". Imo it comes down to how meticulous the owner of a Au is with what fuel they use, where they get it & how often they service their AU's fuel system, its a serious troubleshooting consideration depending on the owner/ previous owner.

cheers,Maka

Sox · 23-09-2013, 11:57 AM

Quote:

Originally Posted by Maka

Ah, i get what your saying now! All i can say is AFI has obviously seen some bad examples as to release a service bulletin, would long term users of e10 for example suffer from fuel rail rusting eventually?

E10 is certainly known for being corrosive, so perhaps so.

Quote:

In the OP, Fanboi found debris in his fpr & it was blocked enough to affect his fuel trims -in his 3rd post - "Given how much crap was in the regulator".

Considering the tiny surface area of the FPR filter, and the unknown amount of k's (we can safely assume over 100,000k's for most AU's though), I think it's an insignificant amount if it were in the tank.
If you've ever drained a petrol tank you'll know what I mean.

I'd go as far to say that over time the rust debris will break down enough to go through the tank filter, through the pump, and end up in the replaceable paper filter.
Some will likely even get through that and combusted through the engine, with IMO no harm whatsoever.

Quote:

Imo it comes down to how meticulous the owner of a Au is with what fuel they use, where they get it & how often they service their AU's fuel system, its a serious troubleshooting consideration depending on the owner/ previous owner.

You're dead right if the filter is in place, however that's why I'm questioning the validity of the filter in the first place.

I guess my question is, will these cars run better for longer without the filter at all.

Maka · 23-09-2013, 12:46 PM

Quote:

Originally Posted by Sox

I guess my question is, will these cars run better for longer without the filter at all.

Probably! That fpr filter is over engineering lol, i'm happy its there though!

cheers,Maka

Sox · 24-09-2013, 06:36 AM

Quote:

Originally Posted by Maka

Probably! That fpr filter is over engineering lol, i'm happy its there though!

I was more thinking along the lines of bad engineering.

I'd like the hear the thoughts of a good fuel specialist.

mik · 24-09-2013, 08:39 AM

i'd rather have the fuel system a bit over engineered than find out on the side of the road it's not, hopefully i haven't just put the moz on myself

.

T4ME · 24-09-2013, 08:46 AM

E10 is not corrosive at all.

Maka · 24-09-2013, 09:49 AM

Quote:

Originally Posted by T4ME

E10 is not corrosive at all.

Your right! i just had a look, e10 runs a corrosion inhibitor so by itself it wont corrode parts in your fuel system but e10 is hydroscopic (attracts water). So does that mean the inhibitor stops the e10 from being hydroscopic? I dont know.

http://www.todaytonightadelaide.com....es/petrol-test -

"Dr Tim White from the University of NSW says, although it's the cheapest fuel on offer, e10 still poses potential problems for Australian motorists.

The problem with e10 isn't so much actually burning the alcohol in the engine. It is that the alcohol is hydroscopic; that it can actually absorb water from the atmosphere when it's in an open tank - particularly in the ground tank at the petrol station.

Water still can get into the fuel system and you may still have these problems of blocked filters and rough running. Even in a brand new car."

cheers,Maka

Sox · 24-09-2013, 10:42 AM

I ain't touching the E10 corrosion debate, that's a whole 'nuther can of worms...
The long term effects of E10 is still somewhat unknown to a large degree, however it is well understood there are some issues.

In any case, this thread is about a filter in the FPR.

xr8cam · 02-12-2014, 11:35 AM

I have a EF 4.0i with the same issues, rough idle, occasional missing and I have replaced all sensors, coilpack,leads,plugs,filters etc but still no difference. So what I am asking I suppose is it possible Iv'e got the same problems? I would really appreciate some feedback as I have been trying to fix these symptoms for 10 months now and I am out of ideas and money

Spurious · 02-12-2014, 11:49 AM

Quote:

Originally Posted by 427camo

I have a EF 4.0i with the same issues, rough idle, occasional missing and I have replaced all sensors, coilpack,leads,plugs,filters etc but still no difference. So what I am asking I suppose is it possible Iv'e got the same problems? I would really appreciate some feedback as I have been trying to fix these symptoms for 10 months now and I am out of ideas and money

The original post on this thread is 2 years old!

Start a new thread as, FYI, bumping really old ones can bug some members.

xr8cam · 02-12-2014, 01:44 PM

Im more interested in a yes or no answer, FYI I have posted many questions over the last few months and have had little help. You read my post today so do you know the answer to my question?

jauser · 02-12-2014, 04:50 PM

Quote:

Originally Posted by 427camo

Im more interested in a yes or no answer, FYI I have posted many questions over the last few months and have had little help. You read my post today so do you know the answer to my question?

Camo ,have u replaced the intake manifold gasget?

fordfalconed · 04-12-2014, 10:12 AM

Gidday Au drivers,

One suggestion would be to also check if your Harmonic balancer is aligned as this can cause the slightest vibration appearing as missfire especially on idling and not so much on load. Just a thought from my AU3 SR petrol sedan.

I changed my spark plugs, coil pack, leads, renewed intake manifold as was leaking then slight vibration continued but noticed slight wobbly harmonic balancer and serpentine belt. Renewed and now purrs at idle with no previous vibration.