Check engine light after oil change

[scott449]

Ok so my 1999 966 C4 was running fine but I needed to change the oil. So I took it to the local guy and all is fine. 2 days later I get a check engine light. I know these things may not be related but thought I would ask when I remembered that my car took 9.2 QT of oil before the dip still read full. According to the owner’s manual it should be full at 8.6.

So right now if I check my dip stick I am not over full on oil also the gage on the consol show that the oil is full but not over full. But the car took more oil than the manual said.

So I guess my question is can over filling oil cause a check engine light?

Any other thought on check engine light as it relates to oil change?

Edited October 22, 2008 by scott449

[Loren]

What model year please? (so we know if it is a 3.4 liter or 3.6 liter as they are different)

You need to get the fault code(s) read - there are literally hundreds of faults that turn on the CEL.

[scott449]

What model year please? (so we know if it is a 3.4 liter or 3.6 liter as they are different)

You need to get the fault code(s) read - there are literally hundreds of faults that turn on the CEL.

1999 so i think that is a 3.4 liter.

I know there are a large # of codes that turn on the CEL. but i was wondering if any are related to overfilling to oil? and if simply draining some oil will correct the issue.

[Loren]

A MY99 3.4 liter will take 8.98 US quarts with filter change. You can just take the filter off - pout out the contents and put it back on.

The only way I can think of too much oil causing a cell is if it gets sucked into the intake (which likely means a bad Air/Oil Separator).

You need to have the code read - as it may not be related to the oil overfill.

[CMiYC]

I know there are a large # of codes that turn on the CEL. but i was wondering if any are related to overfilling to oil? and if simply draining some oil will correct the issue.

While not as good as other tools, an OBD reader can give you some clue. Just stop by your local AutoZone and borrow theirs to read the code(s).

(Again, this is pretty minimal, but it would at least give you a clue to what turned on the CEL.)

[scott449]

A MY99 3.4 liter will take 8.98 US quarts with filter change. You can just take the filter off - pout out the contents and put it back on.

The only way I can think of too much oil causing a cell is if it gets sucked into the intake (which likely means a bad Air/Oil Separator).

You need to have the code read - as it may not be related to the oil overfill.

I could be wrong just ask my wife! but if it was the Air/Oil Separator would i not be getting smoke?

haveing the codes read today.

[Loren]

You asked how overfilling could affect the CEL - I told you a possibility - I did not say you had a bad AOS.

I said check the fault codes.

[scott449]

thanks for the help

It was a bad O2 sensor #1 on bank #2 I believe this is the O2 sensor before the CAT but I am not 100% sure anyway I had the mech. suck out the extra oil and the light went away after about 30 miles.

Perhaps these are totally unrelated and it is just one of those strange things that happen but who know.