4 engine faults in 3 weeks

[thePHILosipher]

I really need some help here,
for the past month i have been having continual engine trouble, i have gone through 3 egr valves in the space of 1500 miles and a new air mass meter. The car has been ripped apart by the local stealer yet first thing this morning the EML came back on..... AGAIN!!!!

Gods honet truth is that everytime that the light has come on i have been sitting on a cruise at about 60-70mph off boost. The dealer has supposidly checked all the electrics all the engine components and all is supposed to be 'fine' yet the light keeps coming on and the car keeps going into limp mode.

Its only done just shy 32500 miles and is on a 56 plate (ibiza FR TDi)

Anybody got any idea's at all about what could be causing it or have i got myself a friday car here??

thanks guys

 

[oldman]

best thing to help you and us, is get a vag-com full scan and see what the outcome is.
egr's are not cheap new, so hope all been done under warranty.

what reasons for changing bits has the garage given?
assume checked all pipes have no splits/tears in them and attached correctly?

 

[thePHILosipher]

yep all done under warrenty thank god (as it does expire on tuesday)

they have replaced the parts as that is 'Where they have traced the fault to' sounds like to me lol.

Im taking it to my local VAG specialist that has done all the mods/services to the car on wednesday and see what they say.

Apprently they called in their 'Cheif' techie to inspect the car over and they had it for 4 days and did 100 miles worth of driving with it (i checked with the odometer) so i can only hope that they have checked for all the basic bits like pipes etc, but then again this is a stealer.

Thinking about it today, the light has only come on whilst sitting on the cruise for about 5 miles, could that have something to do with it?? I know that it seems a long shot as everything seems to fuel related but the light has come on initially everytime whilst on the cruise.

 

[andycupra]

id have a chat with the dealer and seat tomorrow regarding the warranty and that this issue have not been resolved despite several attempts and opportunities for the dealer to correct it. As such i would have concern that when the warranty expires they drop it, or alternatively say its fixed, then next week it comes back.
I would therefore request that this issue is noted on file and that they will provide an extension to the warranty for this issue. (a year would seem reasonable to me).

I guess the problem is they appear to be quessing somewhat.

 

[thePHILosipher]

it does sound that way doesnt it, i also get the feeling that they are deliberately trying to move to after the warrenty so they can land a nice bill at my door.

Cheers for the advice i will have to have a word with SEAT UK and try and get the warrenty extended for this fault. The cars going in for 8am tommorow morning probably for yet another week, or wednesday (which ever comes first) its just so damn annoying, i love the car, but this is becoming a joke

 

[andycupra]

keep all documents and record when and how long the dealer has it. Make sure dealer provides a print out to back up when they have had the car.

good luck.

 

[oldman]

along with the above advise,
Do you know what the actual is? or the reason for changing those bits?
I mean they should have been able to give the fault codes you were experiencing so you could at least have an idea what they were going to be doing and why.
I always ask for check info as they generally do a vag-com by default on a service so I know what is being done and why, always fell like stinging you!

 

[thePHILosipher]

thanks for all the advise guys really appreciate it

spoke to them today and the past 2 occasions the fault code that was showing was P0401 EGR.

I was speaking to an indi. garage and they said that there's 2 good possibilities. Injectors (i've forgoten the link he gave me to the EGR) or a hole in the hoses somewhere (even tho the garage where supposed to have checked them). If theres a hole then obviously more air in the system, more fuel, overflow the EGR, then poof?? does that sound right??

He's saying that the fault is almost certainly within the fuel delivery system just a question of where??

The garage however are trying to change the EGR again and give me the car back.

I've spoken to SEAT customer services and they have confirmed that regardless of the fact that the warrenty has officially expired, the fact that the fault has been ongoing for so long they will guarentee it for another 30k providing i report all faults within a reasonable amount of time after, considering my current record of 1hr dont think that'll be a problem

The other outcome is that if the fault happens again then there is a strong possibility that they will have to take the car off me for 500-1k miles and try to pin point all faults when they happen.

I'll keep you posted

 

[oldman]

ask garage for teh full error description and other codes.
doing a google, i found this:
http://forums.tdiclub.com/showthread.php?t=151068

which gave me:
16785
P0401
Exhaust Gas Recirc.Flow Insufficient Detected

and i get this every other day.
doing a search on here and others like vwvortex & tdiclub you'll find it isn't anything major to worry about. I clear the code every weekend and not had any issues at all.
Only had this since i removed and cleaned the EGR as so clogged i'm surprised car actually worked. It i snot part of any service to have it chcked according to seat as i asked when i knew how bad it was.

Only way to get the egr removed from system is to have a remap as on edc15 ecu cars can it be modified which may help.

if you do get a complete resolution from seat do let us al know as be interesting.

 

[Viking]

Ross Tech gives this info...

Link.

 

[Viking]

Just thinking out loud, the EGR wouldn't throw it into limp mode usually (I don't think) but would throw the engine light on. However, the turbo actuator system would throw limp mode if it failed to provide the correct boost. And what common item is relevant to both these? Vacuum. I suspect you have a vacuum issue, either a faulty tandem pump which is dropping both vacuum (causing the egr/eml issue and limp mode due to loss of turbo) and fuel pressure to the injectors (gives you poor running due to lack of fuel), or a leaking vacuum hose/system. More likely to be the tandem pump to me though.

Like I said though, just thinking out loud.

 

[thePHILosipher]

Ross Tech gives this info...

Link.

yep thats pretty much spot on on the symptoms apart from my car tends to go into limp mode.

The garage where supposed to have checked all the wiring last time and then 'pin pointed the fault to the air mass meter'

when i spoke to them about an hour ago they said that they will be removing the egr control unit from a donar car (if its the one i think it is, with an extra 12k on the clock)' and fitting that, they will confirm to me by 5pm today what they are going to do. It does seem to be that they are just guessing whats wrong rather than having any knowledge.

Quote: 'if you do get a complete resolution from seat do let us al know as be interesting. '

yeh i will do defo, at least its not just me thats experiancing this fault. I'm hoping that it will finally be sorted so that i can continue enjoying my lil derv and get my remap done in a couple of weeks.

 

[thePHILosipher]

Just thinking out loud, the EGR wouldn't throw it into limp mode usually (I don't think) but would throw the engine light on. However, the turbo actuator system would throw limp mode if it failed to provide the correct boost. And what common item is relevant to both these? Vacuum. I suspect you have a vacuum issue, either a faulty tandem pump which is dropping both vacuum (causing the egr/eml issue and limp mode due to loss of turbo) and fuel pressure to the injectors (gives you poor running due to lack of fuel), or a leaking vacuum hose/system. More likely to be the tandem pump to me though.

Like I said though, just thinking out loud.

nice one!! so vacuum is more likely. The link between the 3 things (eml,egr,limp mode) also makes it much more likely.

Also the light only ever come on whilst at speed on the motorway/a road or accelrating from a roundabout (the first time this all kicked off) so that coupled with everything else would point the finger in that direction

That is one i will be throwing at them tonight when they call or running past Ali tommorow.

Cheers mate, if that solves it, i think i'll be oweing you all a pint

 

[thePHILosipher]

ok car's back, working ok for now, its been tested for 185 miles now and working ok.

they have changed the egr valve, air filter and n75.

the last fault code that came up was P0402 egr limit exceeded.

The way that they tested it was by using the EGR components from another car, tested it, then replaced the old parts until the fault came back again, the part which triggered the the EML was the N75.

I've got the invoice

Needless to say im still skeptical about if its solved it or not but i suppose we will see over the next 300miles and see what happens. I'm having it looked at again on monday by my usual garage and get a second opinion.

 

[Viking]

The N75 valve is a vacuum control for the turbo actuator. Nothing to do with the EGR I'm afraid (although there's a similar valve which does control the EGR).

 

[oldman]

when i removed & re-added my egr it didn't come on for over 400miles (trip to gatwick airport & back) then promptly came on 400yrds from drive on way to work -> very random as to when it does do this.

if n75, might change mine and see if the clears it.
do you have part number & price please phil?

 

[thePHILosipher]

when i removed & re-added my egr it didn't come on for over 400miles (trip to gatwick airport & back) then promptly came on 400yrds from drive on way to work -> very random as to when it does do this.

if n75, might change mine and see if the clears it.
do you have part number & price please phil?

hiya the part number on the invoice is 6Q0906625G. Im afraid i dont have a price as it was done under warrenty.

I spoke a little to soon as guess what the bloody light came back on on the way home from work this is getting annoying. The car has run alot better with the replacement parts but dont help when it triggers the sodding light. Im starting to think there could be a fault with the sensor as this is just takin the micky.

Is there anything else that could be triggering it?? The car didnt go into limp today........

 

[oldman]

sorry fella, annoying ye, but if we knew the actual error code may be able to help.

since i removed and cleaned mine, as said i get this all the time, and it does not affect driving manner at all.
the code i get is on another thread, egr dazed & confused, but will try and put on later as know it needs clearing.
reading around it is nothing to worry about as well.

can you get vag-com on it?
put request in the request section of vag-com

 

[muddyboots]

I *think* the way the ECU detects an EGR fault, is by monitoring the airflow via the MAF.
When the EGR is operational, the engine takes in a mixture of fresh air (quantity measured by the MAF) and some exhaust gas (via the EGR valve, quantity not directly measured).
So when the EGR is operating, you'd expect less airflow over the MAF than if it wasn't, as less fresh air is required.
If the ECU thinks the EGR should be operating, it will expect a lower MAF reading.

So - if the ECU thinks there is an EGR fault, it is because it's being told there is too much air flowing over the MAF (and therefore insufficient flow of exhaust gas through the EGR).

This could mean the EGR is faulty (hence 3 new EGRs) - but it could also mean the MAF is giving incorrect readings (hence the new MAF sensor) - or maybe the turbo is boosting a little more than the ECU is telling it to, causing slightly more airflow than expected (not enough to trigger a positive boost deviation, but enough to make it look like the EGR isn't operating).

If the N75 was the culprit, then the latter would seem to be the case...

EDIT: Just read your fault is back again, so it wasn't the N75 then...

If my assumptions are correct about the way the ECU detects an EGR fault, I'm wondering if perhaps a sticky VNT mechanism (or similar fault) means the turbo can't moves the vanes enough to get low enough boost, so you're always getting that tiny bit more airflow when under zero or light throttle.
If you have access to vag-com, might be worth:
1) logging airflow under those conditions
2) run the VNT exercising test to see if it helps free up the VNT mechanism.

Given what's been changed so far, not sure what else it could be...

Is the car standard or remapped ?

 

[thePHILosipher]

I *think* the way the ECU detects an EGR fault, is by monitoring the airflow via the MAF.
When the EGR is operational, the engine takes in a mixture of fresh air (quantity measured by the MAF) and some exhaust gas (via the EGR valve, quantity not directly measured).
So when the EGR is operating, you'd expect less airflow over the MAF than if it wasn't, as less fresh air is required.
If the ECU thinks the EGR should be operating, it will expect a lower MAF reading.

So - if the ECU thinks there is an EGR fault, it is because it's being told there is too much air flowing over the MAF (and therefore insufficient flow of exhaust gas through the EGR).

This could mean the EGR is faulty (hence 3 new EGRs) - but it could also mean the MAF is giving incorrect readings (hence the new MAF sensor) - or maybe the turbo is boosting a little more than the ECU is telling it to, causing slightly more airflow than expected (not enough to trigger a positive boost deviation, but enough to make it look like the EGR isn't operating).

If the N75 was the culprit, then the latter would seem to be the case...

EDIT: Just read your fault is back again, so it wasn't the N75 then...

If my assumptions are correct about the way the ECU detects an EGR fault, I'm wondering if perhaps a sticky VNT mechanism (or similar fault) means the turbo can't moves the vanes enough to get low enough boost, so you're always getting that tiny bit more airflow when under zero or light throttle.
If you have access to vag-com, might be worth:
1) logging airflow under those conditions
2) run the VNT exercising test to see if it helps free up the VNT mechanism.

Given what's been changed so far, not sure what else it could be...

Is the car standard or remapped ?

The car is standard, but as of monday it wont be,

I terms to a resolution, I took the car down to Ali at Unit 18, we plugged it into VAG-com come and the faults that where being recorded where all the egr limit not reached/exceeded, so we changed the perameters within the ECU and so far so good, the light even went out on its own accord Im really hoping that this finally see's the end of it, i did have the VAG-com codes but unfortunately its been mislaid somewhere.