Oil level rise caused by ecu remap ?

[Eagle]

I ve been to a specialist car workshop to try to find the cause of my car having too much lag after fmintercooler and decat exhaust-ecu remap
After running a diagnostic test it gave an O2 sensor error..and i thought this is normal as my car is running with out a catalyst (only with o2 sensor adapter on)
Then the mechanic went for an engine level check and i was wondering why he would do that instead of checking more important things.to my surprice the level of oil rise and there was also a little
bit of oil on the top of the engine near the sparkplug covers.
The mechanic (he has experience with tuned cars)
told me that this is because of
my car running decat in combination with a bad ecu remap -not making the necessary parameter adjustments to the ecu for running decat and this can cause both a significant turbo lag and the oil level to rise.
I am sure the car oil level was ok after my oil change..the head gasket engine is ok too..
didn't know that a decat exhaust can cause this
I never heard before

[Chris_Blue]

News to me too- hopefully an engineer can help us out

Would imagine that you must have a bespoke remap after making a few alterations- I know remaps have to be tinkered with to allow for a different intercooler

[Jamie@SPTuning]

Fuel in oil....fuel wetting of the cylinder walls which is then scraped back to the sump by the piston rings. MED17 makes calculations on how much fuel is in oil, don't ask me how lol

[Eagle]

Is this caused by running an engine with out a catalyst?

[DaveB]

I don't claim to be an expert on the subject, but it sounds to me as though it's been caused, at least in part, by the O2 sensor failure. I suspect that as a result of that the ECU will have been overfuelling.

One thing's for sure - oil diluted with petrol isn't a good lubricant!

[Eagle]

I 've spend 250gbp for a racing 200cpi catalyst to have on my car hopefully to sort the problem...Yesterday I have travel around 150km with my car and my new racing catalyst on..return back home last night...This afternoon I checked the engine level again to see if the catalyst has solved my problem..
To my frustriation it DID NOT...engine oil level rise again just after 150km
any ideas of what could be wrong?

[Jan79]

Is the HPFP at petrol engine powered by the camshaft? Maybe there is a sealing leaking and fuel can get into the oil sump.

[Eagle]

My car has only 11,500 miles I don't think its the hpfp fault that early
On the other hand I don't know if its the remap 's fault or something else that is causing it

[Jamie@SPTuning]

Maybe in remap fuel pressure has been increased and pumps seals are failing leaking fuel into the cylinder head.
120 bar is peak pressure at full load.

[Eagle]

is it possible to be a fault of the inlet pvc valve that is causing this?

[Dangerousfish]

I 've spend 250gbp for a racing 200cpi catalyst to have on my car hopefully to sort the problem...Yesterday I have travel around 150km with my car and my new racing catalyst on..return back home last night...This afternoon I checked the engine level again to see if the catalyst has solved my problem..
To my frustriation it DID NOT...engine oil level rise again just after 150km
any ideas of what could be wrong?

But.. but.. you could have bough my decat pipe for a lot less!

[Eagle]

But.. but.. you could have bough my decat pipe for a lot less!

I already have a full exhaust including decat downpipe and is really loud ��

[Dangerousfish]

I already have a full exhaust including decat downpipe and is really loud ��

Then imagine how loud it would sound with TWO decat pipes!

[Czar]

Eagle can we have some questions answered first:

Can you definitely detect fuel in the oil ?

Have you measured by volume or weight at just how much the oil level increases ?

Have you ever changed the high pressure fuel pump, do you know if it's still the factory original ?

Did your tuner adjust the fuelling parameters ?

Lastly; have you done a compression check and leakdown test to see if you have a weak or dead cylinder, which would be taking the fuel supplied, and losing it straight into the oil sump !!!

[Eagle]

Eagle can we have some questions answered first:

Can you definitely detect fuel in the oil ?

Have you measured by volume or weight at just how much the oil level increases ?

Have you ever changed the high pressure fuel pump, do you know if it's still the factory original ?

Did your tuner adjust the fuelling parameters ?

Lastly; have you done a compression check and leakdown test to see if you have a weak or dead cylinder, which would be taking the fuel supplied, and losing it straight into the oil sump !!!

Hi Czar..
A little background info...After having my intercooler there was a lag between 3,200-3800 rpm..went back to my tuner to adjust it ..tuner installed a version 2 for 205-210bhp and also did some tweaks but this did not sort the lag problem so he suggested to have a smoke test to test for any leaks in the intercooler pipes..Went to mechanic with experience in tuned cars...smoke test did not showed any leaks..however the diagnostic tool showed an o2 sensor failure..he also checked the oil level and it was about half finger
higher than normal so we remove the excess oil ..oil level left to just below max level....also I went for a racing catalyst as well to see if it will sort the lag and the oil level rise problem.
after having the racing catalyst on I drove the car for a 150km trip
the next afternoon I open the bonnet to check the oil level again *(using the dipstick)...Oil level was about 2 fingers higher than max and also the dipstick had a fuel smell
My car has 18,000km only...never checked the high pressuer fuel pump...yes its the oem factory on
Haven't done any compression test

My tuner is suspecting that the pcv valve has broke