Oil overfill and resulting issues - next steps advice needed
Discussion
Hi Folks,
Will try to keep this brief!
Got my Megane RS 275 car serviced earlier this year. It came back running badly and a few days later the check engine light came on.
The exhaust stank too - of oil. Checked oil level. Was WAY too full.
Spoke to servicing garage but they had their Teflon suits on and did not own up - they just cleared the fault codes.
Took car to friendly local garage who took about 2l of oil out and it was still reading just on max oil level.
Car still running crap so I replaced the plugs and coils on the basis that they were likely to be shagged from oil contamination. The plugs were horrendous. One was actually covered in oil and was even lose. The oil was all the way up the pencil coil too.
After replacing the plugs and coils the car runs way better but still running rich and a bit lumpy on idle.
Decided to get another garage to drain and replaced the oil just to be safe.
Still running rich and rough.
Finally caved and took it in to Renault main dealer this week. Diagnostics inconclusive (£150 first pass) and they suggested another 3 hrs of diagnostics for the bargain price of £550! Nice.
However after cross examining them they did eventually tell me that that the upstream oxygen sensor was running out of spec - resistance too high.
Hmm, well that makes sense right? Almost certainly goosed due to being covered in partially combusted engine oil and probably explains why the car is not running very well.
So, rather than embark on main dealer diagnostic bingo at £550 per go I think I'll just replace the O2 sensor (about £150) and see if that sorts things out.
Is it reasonable to assume that a huge excess of oil would result on engine warning lights, stinky exhaust, shagged plugs / coils, rough running and a knackered O2 sensor?
I'm tempted to invoke Occam's razor on this and go with the most likely explanation rather than commit to to eye wateringly expensive diagnostics to probably come to the same conclusion.
Thoughts / suggestions welcome.
Will try to keep this brief!
Got my Megane RS 275 car serviced earlier this year. It came back running badly and a few days later the check engine light came on.
The exhaust stank too - of oil. Checked oil level. Was WAY too full.
Spoke to servicing garage but they had their Teflon suits on and did not own up - they just cleared the fault codes.
Took car to friendly local garage who took about 2l of oil out and it was still reading just on max oil level.
Car still running crap so I replaced the plugs and coils on the basis that they were likely to be shagged from oil contamination. The plugs were horrendous. One was actually covered in oil and was even lose. The oil was all the way up the pencil coil too.
After replacing the plugs and coils the car runs way better but still running rich and a bit lumpy on idle.
Decided to get another garage to drain and replaced the oil just to be safe.
Still running rich and rough.
Finally caved and took it in to Renault main dealer this week. Diagnostics inconclusive (£150 first pass) and they suggested another 3 hrs of diagnostics for the bargain price of £550! Nice.
However after cross examining them they did eventually tell me that that the upstream oxygen sensor was running out of spec - resistance too high.
Hmm, well that makes sense right? Almost certainly goosed due to being covered in partially combusted engine oil and probably explains why the car is not running very well.
So, rather than embark on main dealer diagnostic bingo at £550 per go I think I'll just replace the O2 sensor (about £150) and see if that sorts things out.
Is it reasonable to assume that a huge excess of oil would result on engine warning lights, stinky exhaust, shagged plugs / coils, rough running and a knackered O2 sensor?
I'm tempted to invoke Occam's razor on this and go with the most likely explanation rather than commit to to eye wateringly expensive diagnostics to probably come to the same conclusion.
Thoughts / suggestions welcome.
E-bmw said:
Can't see how it would affect coils, personally I wouldn't have swapped them.
Oil in the coil well is more likely (not definitely not) to be from a weeping rocker cover gasket leaking into it.
The coil that had oil on it was the one for the spark plug that was lose - and which had oil all over the plug thread.Oil in the coil well is more likely (not definitely not) to be from a weeping rocker cover gasket leaking into it.
Is it possible that if they massively overfilled the oil that the oil could get in to the cylinders?
If you had a loose plug, that's because it was not fitted properly. That's a major mistake.
Over filling the oil is a separate major mistake.
Both mistakes suggest that the work was rushed.
If the oil is over filled so far that it covers the windage tray then you can end up with the crank whipping it up. That overheats the oil (it will need replacing) and can also fill crank case and rocker area with oil mist. This will lead to oil in the breather gases, which will then be drawn into the engine and contaminate plugs, EGO sensors, catalyst etc.It's entirely possible that this resulted in the crank case being pressurised and blowing out gaskets or seals, but for all we know the muppet doing the service just dropped the oil bottle.
Over filling the oil is a separate major mistake.
Both mistakes suggest that the work was rushed.
If the oil is over filled so far that it covers the windage tray then you can end up with the crank whipping it up. That overheats the oil (it will need replacing) and can also fill crank case and rocker area with oil mist. This will lead to oil in the breather gases, which will then be drawn into the engine and contaminate plugs, EGO sensors, catalyst etc.It's entirely possible that this resulted in the crank case being pressurised and blowing out gaskets or seals, but for all we know the muppet doing the service just dropped the oil bottle.
GreenV8S said:
If you had a loose plug, that's because it was not fitted properly. That's a major mistake.
Over filling the oil is a separate major mistake.
Both mistakes suggest that the work was rushed.
If the oil is over filled so far that it covers the windage tray then you can end up with the crank whipping it up. That overheats the oil (it will need replacing) and can also fill crank case and rocker area with oil mist. This will lead to oil in the breather gases, which will then be drawn into the engine and contaminate plugs, EGO sensors, catalyst etc.It's entirely possible that this resulted in the crank case being pressurised and blowing out gaskets or seals, but for all we know the muppet doing the service just dropped the oil bottle.
Yup, hard to screw up a plug and oil service but they managed it on all counts. Should have just done it myself. Over filling the oil is a separate major mistake.
Both mistakes suggest that the work was rushed.
If the oil is over filled so far that it covers the windage tray then you can end up with the crank whipping it up. That overheats the oil (it will need replacing) and can also fill crank case and rocker area with oil mist. This will lead to oil in the breather gases, which will then be drawn into the engine and contaminate plugs, EGO sensors, catalyst etc.It's entirely possible that this resulted in the crank case being pressurised and blowing out gaskets or seals, but for all we know the muppet doing the service just dropped the oil bottle.
I'll get the upstream lambda sensor replaced and see how it runs from there.
I have had two cars overfilled with oil at a service (Volvo C30 and V40). Standard excuse is there is no dipstick and the display takes a while to register the new oil, so they just drain the oil and refill with the recommended amount. I assume they didn't completely drain the oil, so ended up with too much in total. Engine lights came on both times, so the level was corrected before any damage was done. Maybe I was just lucky ?
Red9zero said:
I have had two cars overfilled with oil at a service (Volvo C30 and V40). Standard excuse is there is no dipstick and the display takes a while to register the new oil, so they just drain the oil and refill with the recommended amount. I assume they didn't completely drain the oil, so ended up with too much in total. Engine lights came on both times, so the level was corrected before any damage was done. Maybe I was just lucky ?
Interesting. Glad you avoided any damage. My car actually has both a digital readout and a dipstick - but to be fair (if I really have to) the dipstick is almost impossible to read, and the digital display just shows 5 dots out of 5 when it is full, rather than saying "overfilled" or anything remotely useful like that.
Even so, that fact that the next mechanic (different garage) took out 2 litres of oil and it still read just on max on the dipstick shows a monumental lack of care by the original garage.
Hopefully the new O2 sensor will get it back to normal running.
TorqueDirty said:
Red9zero said:
I have had two cars overfilled with oil at a service (Volvo C30 and V40). Standard excuse is there is no dipstick and the display takes a while to register the new oil, so they just drain the oil and refill with the recommended amount. I assume they didn't completely drain the oil, so ended up with too much in total. Engine lights came on both times, so the level was corrected before any damage was done. Maybe I was just lucky ?
Interesting. Glad you avoided any damage. My car actually has both a digital readout and a dipstick - but to be fair (if I really have to) the dipstick is almost impossible to read, and the digital display just shows 5 dots out of 5 when it is full, rather than saying "overfilled" or anything remotely useful like that.
Even so, that fact that the next mechanic (different garage) took out 2 litres of oil and it still read just on max on the dipstick shows a monumental lack of care by the original garage.
Hopefully the new O2 sensor will get it back to normal running.
GreenV8S said:
If you had a loose plug, that's because it was not fitted properly. That's a major mistake.
Over filling the oil is a separate major mistake.
Both mistakes suggest that the work was rushed.
If the oil is over filled so far that it covers the windage tray then you can end up with the crank whipping it up. That overheats the oil (it will need replacing) and can also fill crank case and rocker area with oil mist. This will lead to oil in the breather gases, which will then be drawn into the engine and contaminate plugs, EGO sensors, catalyst etc.It's entirely possible that this resulted in the crank case being pressurised and blowing out gaskets or seals, but for all we know the muppet doing the service just dropped the oil bottle.
This all over - I'd remove the O2 sensor first and see how it looks, if it's absolutely crusty with oil residue might be worth just cleaning it up and refitting, otherwise just throw a new sensor in.Over filling the oil is a separate major mistake.
Both mistakes suggest that the work was rushed.
If the oil is over filled so far that it covers the windage tray then you can end up with the crank whipping it up. That overheats the oil (it will need replacing) and can also fill crank case and rocker area with oil mist. This will lead to oil in the breather gases, which will then be drawn into the engine and contaminate plugs, EGO sensors, catalyst etc.It's entirely possible that this resulted in the crank case being pressurised and blowing out gaskets or seals, but for all we know the muppet doing the service just dropped the oil bottle.
Keep an eye on the plug wells etc for excess oil, you may have a busted seal somewhere which is also contributing.
TorqueDirty said:
Finally caved and took it in to Renault main dealer this week. Diagnostics inconclusive (£150 first pass) and they suggested another 3 hrs of diagnostics for the bargain price of £550! Nice.
I'd say most main dealers would struggle to diagnose high oil level let alone much else. Mental quote too. No wonder any sane person would avoid themWere the clowns that overfilled it, even touching the plugs or coils ? What is the cars history ?
The loose plug could well be unrelated, and down to poor maintenance prior. And only one coil filled with oil ? May or may not be related to the current overfill scenario
Should get the old oil that was drained out, and pour it over the garages service desk
stevieturbo said:
I'd say most main dealers would struggle to diagnose high oil level let alone much else. Mental quote too. No wonder any sane person would avoid them
Were the clowns that overfilled it, even touching the plugs or coils ? What is the cars history ?
The loose plug could well be unrelated, and down to poor maintenance prior. And only one coil filled with oil ? May or may not be related to the current overfill scenario
Should get the old oil that was drained out, and pour it over the garages service desk
I bought it new in 2016. 275 Cup-S with most of the nice options. Full dealer SH until I decided to take it to this more local garage ( I live out in the sticks in Scotland) . Never tracked. 25k miles. Were the clowns that overfilled it, even touching the plugs or coils ? What is the cars history ?
The loose plug could well be unrelated, and down to poor maintenance prior. And only one coil filled with oil ? May or may not be related to the current overfill scenario
Should get the old oil that was drained out, and pour it over the garages service desk
And it was running perfectly before.
Actually traded in an XKR 5.0 for it!
Old oil long gone.
Red9zero said:
I have had two cars overfilled with oil at a service (Volvo C30 and V40). Standard excuse is there is no dipstick and the display takes a while to register the new oil, so they just drain the oil and refill with the recommended amount. I assume they didn't completely drain the oil, so ended up with too much in total. Engine lights came on both times, so the level was corrected before any damage was done. Maybe I was just lucky ?
Volvos are a pain, you under fill them then use diagnostics to calculate the oil level. It takes an additional 20-30 minutes on a Volvo to carry out a service.TorqueDirty said:
I bought it new in 2016. 275 Cup-S with most of the nice options. Full dealer SH until I decided to take it to this more local garage ( I live out in the sticks in Scotland) . Never tracked. 25k miles.
And it was running perfectly before.
Actually traded in an XKR 5.0 for it!
Old oil long gone.
So was this new place touching the plugs ? Or was the plug loose from the previous, likely dealer install ?And it was running perfectly before.
Actually traded in an XKR 5.0 for it!
Old oil long gone.
Dealer history is often a cause for concern. They like ticking boxes, washing cars. Doing the work you expect them to, to a high standard ? not so much
Either way, an odd situation to be in
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