p00087 -fuel pressure too low

[saj_a6]

Hi folks, looking for a bit of friendly community advice into a problem and the way the dealers are managing it.

History is I have a 3.0 TDI Quattro, automatic. Bought it Audi approved used car scheme 22 months ago, had Audi services since I’ve had it and only had audi services looking through the services book.

At the end of November noticed one morning on starting the car that the engine management light (coil symbol) was flashing. At the same time could see that the engine kept sounding as if it would momentarily under rev and then pick up as though over compensating and trying not to stall. Turned the engine off and back on the warning light was gone and she drove fine without any issues.
Over the next week noticed it would tend to do this when first starting the car in the mornings, or when setting off and soon after coming to an idle at the end of the road.
If I got going and didn’t have to stop would stay off and drive fine, same if I turned the engine off and back on and drive steadily at speed without having to slow down to a halt.

Took it to a local garage who I was picking some front tyres off and got them to just run a quick diagnostic and it showed
P0087/000135 - Fuel Rail/System Pressure: Too Low, they suggested trying to change the filter first but mentioned could also be the fuel pump or sensor.
At this point were due to drive to centreparcs so figured I’d change the filter myself. Changed it over and (albeit to a eurocarparts filter as it was easier to get hold of on the weekend) and drove with things looking ok. However on returning problems picked up again and gradually more frequent and to a couple of occasions where the engine stalled coming to a set of lights.

So eventually booked it in with Audi as was due a service as well at the end of December.
Car currently is 11 month out of the approved scheme warranty. Bank holidays didn’t help in getting the car through some diagnostic tests but initially the garage claimed they couldn’t diagnose the fault. Apparently this has involved sending information from the garage to Milton Keynes and Germany and at times waiting to hear back any advice re further tests or possible causes.
Had tried changing the fuel filter to an audi one with no improvement. They’ve told me they’ve looked at the fuel pump and cant see any sign of damage/metal shavings as described in some of the posts I’ve seen online.
The latest is they are waiting for ‘donor car’ so that they can try swapping some of the parts such as the fuel pump to see if it clears the problem before ordering brand new parts ?!

Now been a month, and although it’s been great to have a courtesy car for work, a bit frustrated by the whole situation. They have agreed that there would be some Audi goodwill towards the cost and keep assuring me they’ll look after me and I won’t get lumbered with a ridiculous bill of 2-3 grand.

Part of me sits there thinking may be should be patient and as its not under warranty any more maybe this is the best way to diagnose the fault correctly the first time so I’m not coming back and forth with the car. The skeptic in me feels a month is taking the p***.

So that’s the situation at the moment and just wondered what thoughts people had about the initial fault and of Audis handling of the situation.

[dan2485]

The tank fuel lift pump would be the next port of call.

This normally causes the car to start to loose power on hils etc.

[KjetilRos]

16471/P0087/000135 - Ross-Tech Wiki (http://wiki.ross-tech.com/wiki/index.php/16471/P0087/000135)

Probably fault in tank pump

[saj_a6]

cheers for the ross tech link. saw a couple of other forum posts stating similar. Will speak to the Audi garage and see if they've at least ruled out all those causes.

[Alan02]

Has the rail pressure sensor and regulator been checked? Also HP pump pressure tested?

[MarkTM]

They have agreed that there would be some Audi goodwill towards the cost and keep assuring me they’ll look after me and I won’t get lumbered with a ridiculous bill of 2-3 grand.


Bill will be £1999.99 inc VAT then:confused:

I would suggest

A) you invest in VCDS to do the diagnostics yourself, since you sound like you know your way around an engine
B) Please post in a larger font as yours is a complete pig to read

Sadly I don't live closer, I have a 3.0 quattro 07 (don't think you stated your year), and would have happily been your donor car :)

Do our cars have fuel pressure regulators? My Jaguar had a similar issue as yours and that was the cause, luckily a £30 DIY change

[c4a5er]

It sounds like they are trying to keep costs down as much as possible for you....IMO it's very rare to find a dealer prepared to try parts from a similar car to aid diagnosis, normally they would throw everything at it at your expense. If it were me i'd be happy with the use of a courtesy car for as long as it takes rather than risk a bigger bill by putting pressure on them for a quicker fix.

[saj_a6]

sorry bout the font, glad its a bit more readable now :D
Not sure about knowing myself around an engine but much the wiser thanks to this forum.

Mine is 09 facelift model

Put the sceptic in me to rest for the last week as you said c4a5er and just been enjoying the car while they look into the matter.

They've come back to me asking for go ahead to try changing a few parts, struggled to get a donor car and we decided we couldnt just keep hanging around. been a month now already.

They're still none the wiser with the diagnosis and suggested either 2 options.
Either the fault lies with the fuel rail ( I'm assuming this would mean covering the possibility of it being the fuel rail sensor and regulator perhaps Alan?) and the cost of replacing the fuel rail was quoted as aorund £500 including labour. Of which 50% would then be covered by goodwill.
Alternatively they suggested replacing the fuel rail, fuel pump and some of the fuel lines to a tune of £2600, again with a 50% contribution of this cost by audi.

I opted for replacing the fuel rail.
time to keep those fingers crossed otherwise might end up being £1999 (still got to pay for the service an pads..)

[Alan02]

Unless audi dont recommend replacing the sensor or regulator seperately, I dont see why they need to replace the whole rail? Could be as simple as a split in the o-ring on the regulator?

[dan2485]

Why should you pay for their fault finding.

if they fit parts and it does not fix it, get them to put the old ones back on.

I I would be concerned that a dealer can't fix a fuel issue quickly.

With thy the time that your car has been with them you could have rebuilt the complete fuel system and more.

[saj_a6]

Why should you pay for their fault finding.

if they fit parts and it does not fix it, get them to put the old ones back on.

I I would be concerned that a dealer can't fix a fuel issue quickly.

With thy the time that your car has been with them you could have rebuilt the complete fuel system and more.


Think for a while I've been trying to be optimistic about the situation. When they finally came back with a potential fix which might only set me back £250 i obviously let my guard down a bit and didn't feel the need to fight any more in the situation.
Think looking back on it all I've been a little naive and not put enough of a complaint up....

Just got an email today telling me that the fuel rail repair hasnt fixed the issue and they're ordering a fuel pump to further progress the repair ...:(

Tried getting in touch with Audi at macclesfield but no reply so sent an email today explaining I wasnt happy with paying for items that hadnt made any difference to the original fault. Also havent been given a breakdown of the potential £2500 cost for "fuel pump and other items" so have asked them to provide this and hold off further repairs until I've had chance to speak with them further.
Not sure whats the best next step though, do I take it elsewhere for a second opinion now or try going back to the slower first option of trying to get in a donor vehicle to diagnose the fault properly the first time.

[saj_a6]

This was the latest reply from the audi garage.

Due to the nature of the fuel pressure fault a simple computer “ plug in” does not give us a full breakdown of the fault hence the search for a donor vehicle to transpose parts across which would help with the diagnosis.
With no suitable vehicle available after an exhaustive search the only option is to replace the 3 units responsible for fuel pressure starting with the least expensive and what was potentially the most likely cause of the issue.
With the fuel rail now eliminated the only possible cause now lies with the high pressure pump and connecting pipe.
The parts cost are
1 Fuel pump £1453.44
2 Connecting pipe £131.09
3.Fuel rail £595.72
4. Labour 3.3 hours
This brings a total to £2615.85 inc
Macclesfield Audi and Audi UK will make a 50% contribution towards the repair.

I know its steering away from the overall question as to the quality of service but does that price seem right for the above repair?

[dan2485]

You should only pay for the defective item.

Get them t put the old bits back on at their expense.

Both Audi and the dealer should honor this as the time it's taken.

As you took the hire car I'm not sure where you stand regarding this.

[Alan02]

I wouldnt pay for the parts they fit to eliminate the fault, yes, maybe a contribution by you for their labour but thats it. What assistance if any have they had from Audi?

[saj_a6]

Written to audi uk and have told the garage not to fit any more of the ordered parts until I can evaluate things further.
Have basically asked for them to consider improving the good will and price, including taking out the charge for parts which ultimately were fine in the first place. Or helping to diagnose the fault further to save having to replace so many parts in the first place.
Hopefully they can also tell me what input they have had already in this whole affair.

Failing that was trying to look into my options of alternative solutions. Saw a link to Diesel bob and theyre not too far aweay from manchester.
http://www.dieselbob.co.uk/
anyone had any experience of them with theyre refurbished fuel pumps?

[MarkTM]

^^^They'll have no better diagnostic equipment than a main Audi dealer, personally I'd concentrate on Audi fixing it and the Audi contribution rather than diverting your attention elsewhere.

In for a penny in for a pound (or thousands)!

Can I ask a couple of questions

1) Have you ever towed in the car?
2) Has it ever had a tuning box fitted to it

Ask these as in no Audi cars the above were the main reasons for the code appearing (according to google)

[saj_a6]

no engine modifications (tuning or remaps) to this vehicle. and never been towed before.
did try a cotton air filter on it to see what difference it mgiht make to performance and mpg but thats all.

[MarkTM]

Did the filter make any difference, didn't think there were any performance filters for our cars? What did you fit?

[saj_a6]

it was a jetex cotton filter thinkit was around £30-40
no change to mpg but definately felt it accelerate through the rev range a bit more freely.

[MarkTM]

Thanks, I'll pass, as just change mine with a -£5 aftermarket one off ebay every 5k miles, so the air is always as clean as possible/practical.

Audi A6 3.0 TDI quattro OE Genuine AIR Filter Service Car TF18025 | eBay (http://www.ebay.co.uk/itm/Audi-A6-3-0-TDI-quattro-OE-Genuine-AIR-Filter-Service-Car-TF18025-/330883079159?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Car+Make%3AAudi%7CModel%3AA6%7CCars+Year%3A20 07%7CPlat_Gen%3A4F2%2C+C6%7CCars+Type%3A3.0+TDI+qu attro&hash=item4d0a2b1bf7)

Always good to post links :)

[c4a5er]

This was the latest reply from the audi garage.

Due to the nature of the fuel pressure fault a simple computer “ plug in” does not give us a full breakdown of the fault hence the search for a donor vehicle to transpose parts across which would help with the diagnosis.
With no suitable vehicle available after an exhaustive search the only option is to replace the 3 units responsible for fuel pressure starting with the least expensive and what was potentially the most likely cause of the issue.
With the fuel rail now eliminated the only possible cause now lies with the high pressure pump and connecting pipe.
The parts cost are
1 Fuel pump £1453.44
2 Connecting pipe £131.09
3.Fuel rail £595.72
4. Labour 3.3 hours
This brings a total to £2615.85 inc
Macclesfield Audi and Audi UK will make a 50% contribution towards the repair.

I know its steering away from the overall question as to the quality of service but does that price seem right for the above repair?

My thoughts/comments....

The fuel rails were never going to make a difference as they act as an accumulator to store pressurised fuel rather than generate fuel pressure. Okay the fuel pressure sender or fuel pressure regulator that fits to them may be suspect parts but not the actual rails themselves. The same goes for the connecting pipe. If they can't tell if a connecting pipe is clear by removal and inspection they're in the wrong job.

The HP fuel pump is obviously and rightly under suspicion but they should also check the delivery rate from the in-tank pump as this supplies the HP pump. If fuel delivery to the HP pump is starved then it will not be able to increase fuel pressure effectively.

[Alan02]

I agree in part what you say, but the rail pressure regulator also plays a part in the fault code. It needs a pressure guage fitted into the fuel system to accurately read pump and then rail pressure. Because of the difficulty the dealer has in diagnosing the fault, this would pinpoint where the low pressure exsists.

[c4a5er]

I was assuming, perhaps wrongly, that the fuel pressure sender had been changed and was included in the £595 for the fuel rail meaning they were happy with the accuracy of the pressure readings it was producing for the diagnostic.

It beggars belief that they would not or cannot carry out some pressure testing with gauges before spending huge amounts of a customers money.

Apart from the pressure before and after the HP pump I would also check for leak back from injectors into the return line.

[Hopmeister]

On my P38 Range Rover to diagnose in tank pump issues I used a glass measuring jug. As others have said it is very simple, you put inline pressure gauges in the right places and then measure the KNOWN output. There, that didn't cost £2,000+. Admittedly not everyone has time or skills on their hands - but this is an AUDI dealer and they should have all the toys and the equipment to do the job.

Still after my experience with Taunton Audi I wouldn't expect anything different to actual skill levels. Fitters, not techs, regardless what their certificates say, the proof was in the pudding for me, they allegedly bled my brakes and didn't know that the Q7 had 8 bleed nipples not four. I use a local indy now. He's the one that found that Audi hadn't bled the brakes fully :beerchug:

If you can stretch to it buy VCDS, it is worth every penny. Being able to diagnose your own problems and keep the print out is very wise before it goes into an Audi dealer.

[Rooboy]

So frustrating reading a thread like this and saying yes, this is my symptoms, only to get to the end of it and there’s no solution. :zx11:

Shout out to the OP, how about a report on what was done to fix it?

[Rooboy]

N290 Fuel metering valve is likely the problem. I’ve ordered a replacement. This post has led me to the solution as detailed in the comments.
Help!!!! Low Fuel Pressure p0087 | Audi A5 Forum & Audi S5 Forum (https://www.a5oc.com/threads/help-low-fuel-pressure-p0087.144665/)