oil and fuel contamination

[yorkie1]

as peeps have said before overfueling can course bore wash where excess fuel gets pass the piston rings mixing with the oil, but would think the exhaust sensor would show something. best get a compression test. If you think its the head gasket get a snuff test {blue liquid suck the air out off your water header tank if stay blue all is good if goes pink you have combustion gases in your water}

 

[OLDOILER]

Tell me more, im interested..

If and it is a big if the pump was built incorrectly [ I assume the car is in warranty and under 60k] and this is the first instance that you are aware of it would have failed before 20k what with pressures and duty cycles etc. If you are still not sure you could call in AA/RAC inspection?
One does question the compedance of some of the techi's though, some are CRAP - "computer says no" syndrom and others are brillaint, also Vag marque ALL use different diag s/w which amazes me!! Vag com does cut across the Vag marques and find a local member that may be able to assist.
But I see that you spoke to a reliable remapper and his judgement was that there was no problem, then he is more than likely right [ I have assumed that you a: do not do sort runs b: you do not have a racing map and injectors on a road car@!.
Seat does look at this web site ocassional - I'm about to confront them on another matter where they say "its not a problem" but using this web site and OTHER Vag marque sites you can find failure trends. Sorry I have gone on a bit. ...........................

 

[DanGB]

Ok thats fine, I upgraded my fuel pump at 20k years ago

 

[Nath.]

you think a fault code would exist for that though?

There are 100's of problems that your engine can develop that the ECU will be oblivious to. To my knowledge the 2.0t engine does not have a petrol detecting sensor inside the sump. If it did it would probably fail anyway

As a side note, a petrol detecting sensor inside the DIESEL tank would be a good idea

As said if you do indeed have petrol in your oil there is a test that a GOOD garage can do to prove it.

 

[SEATgod]

The test to check for fuel in the oil is smell!

If the HP pump was bleeding off pressure into the sump, say goodbye to your camshafts!

It only creates 180 - 350 bar, and you would be complaining of lack of power and not fuel in the oil, the pump is designed in that it cant bleed off as it has a reciprocal pumping chamber. If it did, it would be on the high side!.....ITS NOT THE PUMP!

You get fuel in the oil when you either have excessive crankcase vacuum (turbo petrols run a vacuum crankcase and not a pressure one) or you are throwing so much fuel down its throat you are washing the bores! - Remember these are direct injection so its right over the pistons!

Lets deal with the crankcase vacuum first, you wind up the boost and not widen the inlet tract and a turbo will pull air from EVERYWHERE to satify its need, hence your crankcase vacuum. If this pull is high enough, it will pull past the rings. How much has your remap upped the boost and what have you done to the inlet tract. Remember the gas flow on these engines is high anyway!

The most likely culprit is the over fuelling caused by the mapping. You are a foolish man if you believe that the man made box of electronics will give you a fault code for everything this car does wrong. If you do, why do people ever use Dealers for Fault finding? Your ECU is now hosing your engine to get the more power from it, over fuelling causes an engine to run cooler by the way! The fuel will wash the bores (causing excessive wear) and the fuel can get past the rings, this washing is a never ending circle as the more the bores are washed the more fuel gets past and the more they wear! Your knock sensor has already jacked up your ignition point to deal with the extra fuel but it is obvioulsy not enough to cause an ignition malfunction fault. You mapped it to over fuel, so why would the engine control unit give you a fault code for it........

Get the map off it, change the oil and filter and then run it......does it still pick up fuel?

Mapping is quick, cheap and convenient but it is not the answer!

Have fun!!

 

[estie]

im cool. i just want the car fixed. In another dealers now hopefully going to sort the problem. I was led to believe if the car was over fuelling it would be obvious by the way it drives and by pops and bangs. not noticed an increase in fuel consumption either.

 

[SEATgod]

Not always mate!

Cars are quite clever in that they can try to overcome certain issues themselves!

You wont really feel any driving related issues until 10 - 15 % over fuelling.

A rich fault code wont come on until the average fuel trim is over 20%.

Any problems give me a shout!

 

[robdf2]

I think Rob you need to go away and re-read my post!

The fault codes will aid in diagnosis but are not necessarily the answer!

I never called him foolish, only if he believed that every possible fault on his car has a fault code attached!

I am sorry if you have had bad experineces with a Dealer where they are unable to fix a problem! But that is maybe a topic you and I should discuss in private especially with everything I have done in the past to aid your SEAT experience.....or take it up with the Dealer! They are a representative of SEAT, not SEAT directly!

My point for using Dealers was purely that if the magic box told you the fault, why would you need a Dealer to investigate a fault. If everyone is confident the answer is stored within, all you need is a £12 OBD II reader and you can fix everything!! Or is it that a fault code sometimes has nothing to do with the cause of the fault.

Those of you who know how cars work will be nodding your heads in agreement, those of you dont will be surprised to know that a fault code is useless in the hands of someone without knowledge!

Please remove your emotion from the current calamity of events before you Rob and think of it from the technical side! I was only here to help, if that is not welcome let me know and I will go elsewhere!

To the poster, if you feel I have offended you or been unhelpful then I am very sorry! But my post was written with a playful jovial tone. Not the down trodden hate to all as Rob has portrayed!

Merry Christmas!

i was gratefull for the help i recieved , as you would have been in my situation , 5 months to diagnose a fault and fix it if i remeber correctly.
i will pm you today and hopefully you can restore my faith in this "Experience"
the down trodden hate is my experience and not 1 which i would advise others to taste.

 

[chrisboyle999]

The test to check for fuel in the oil is smell!

If the HP pump was bleeding off pressure into the sump, say goodbye to your camshafts!

It only creates 180 - 350 bar, and you would be complaining of lack of power and not fuel in the oil, the pump is designed in that it cant bleed off as it has a reciprocal pumping chamber. If it did, it would be on the high side!.....ITS NOT THE PUMP!

i have to disagree with some of what youve said;

the hpfp created pressures between 30 and 110 bar. in fact the pressure limiting valve opens at 120 bar.

excess pressure is bled off to the low pressure side of the supply line

it could very well be the pump

 

[SEATgod]

Completely agree if it is a 2.0L FSI.

My apologies , I was under the impression this was a Cupra running on a triple lobe cam rather than the double lobe cam!

These have higher pressures and N276 works slightly differently!

Sorry I have read the posts differently!

Still very difficult for the fuel to get past pump chamber and no HP pump has a over pressure valve!

This is always in the fuel rail.

Money is still on overfuelling! Would be worth looking at RMVB 32 and 33 through VAGCOM if you have it!

 

[chrisboyle999]

it could be me thats got the wrong end of the stick

after all, assumption is the mother of all **** ups

 

[estie]

dont know if it makes any difference but the diagnostics was run not by fault codes but by the variables from the sensors. doesnt make much sense to me. but maybe to people that understand cars. if it is the case the car is over fuelling. i want to know what to do to make the be able to handle it rather than downgrade. im open to opinions and suggestions please dont turn this into a patronising debate. i dont know much about car engines but im not stupid.
c'mon everyone its christmas.