CEL

[thebairdybunch]

Ok some background and maybe some pointers - Ie Am I OK to still drive.

here is the background -- Had the car three years (996 1999) No issues at all - done 25K miles had it serviced on the nail - Actually just had a minor service 400 miles ago ..

Drove the car yesterday did few hundred miles and drove to work today -- Came home Midday .. (left card outside - It has rained heavily)

So 6 hours after driving ie Car is cold - Wife goes to pick up daughter .. Comes home and says that light (the CEL) flashed 5x and then went solid -- Then she drove a little further and it flashed and went solid - Clearly I said if it flashed then YOU should not drive - Anyhow the journey was about a mile so I dont see a huge problem - Plus the light was Solid. Didnt continue to flash.

My symptoms are

Solid CEL

Rough Idle

So I pulled the wiring out of the MAF and disconnected the battery for 1 Min - Reconnected everything - Ran the car - No CEL everything seems fine. It runs just the same as it ever did - Nice and smooth - Power seems there - Engine doesnt feel lumpy like its throw a cylinder or anything really serious

Question --

Are the codes still there if I took it to a dealer .. Or its all gone as as Cleared it down .

Should I suspect MAF and or Coilpacks (ie car is now getting on a bit)

Final question - OK to continue to drive like this ? Temps and oil pressures seem just the same as always . The CEL is only related to Engine Air and fuel mix intake issues - Thats correct isnt it ? -

I know this question has been asked a few times - but I have been confused on the CEL light - Maybe it was dirt on the MAF or water in a coilpack . Is there any way to visually tell >?

Advice much appreciated .

all the best and thanks.

[Loren]

Why take it to the dealer - Autozone and some other parts stores will let you read the codes for free.

Without the codes everything is a guess.

You could wait and see if they come back (if they are off now then it is safe to drive).

if and when they do come back - read the fault codes out and report them here.

[RFM]

Every time the battery is disconnected the codes are cleared and most important, the adaption values are reset to zero, which means that if the problem is very small it will take a long time before the cell comes up again. Take note that the problem is not solved now.

[perryinva]

Are you sure about the codes clearing? I don't think that's correct, as on the 02 I recently purchased, the battery was dead, I repalced it, and then had a cel a few days later due to a loose spark plug wire. SInce I was still unfamiliar with servicing the vehilce I had it flatbedded to a well known local indie that found the loose connection (from the recently done 30k service at a different shop), and told me that none of the previous codes from before the 30k service had been cleared, so he cleared them all. Since you mentioned it was raining heavily, I'd bet cracked coil packs, that only show the cel when wet. Pretty common.

[RFM]

I was not clear enough, disconnecting the battery clears the DME codes and adaption values, at the same time you put in code "Power failure" in several other control boxes.

[OCNYPORSCHE]

Ok some background and maybe some pointers - Ie Am I OK to still drive.

here is the background -- Had the car three years (996 1999) No issues at all - done 25K miles had it serviced on the nail - Actually just had a minor service 400 miles ago ..

Drove the car yesterday did few hundred miles and drove to work today -- Came home Midday .. (left card outside - It has rained heavily)

So 6 hours after driving ie Car is cold - Wife goes to pick up daughter .. Comes home and says that light (the CEL) flashed 5x and then went solid -- Then she drove a little further and it flashed and went solid - Clearly I said if it flashed then YOU should not drive - Anyhow the journey was about a mile so I dont see a huge problem - Plus the light was Solid. Didnt continue to flash.

My symptoms are

Solid CEL

Rough Idle

So I pulled the wiring out of the MAF and disconnected the battery for 1 Min - Reconnected everything - Ran the car - No CEL everything seems fine. It runs just the same as it ever did - Nice and smooth - Power seems there - Engine doesnt feel lumpy like its throw a cylinder or anything really serious

Question --

Are the codes still there if I took it to a dealer .. Or its all gone as as Cleared it down .

Should I suspect MAF and or Coilpacks (ie car is now getting on a bit)

Final question - OK to continue to drive like this ? Temps and oil pressures seem just the same as always . The CEL is only related to Engine Air and fuel mix intake issues - Thats correct isnt it ? -

I know this question has been asked a few times - but I have been confused on the CEL light - Maybe it was dirt on the MAF or water in a coilpack . Is there any way to visually tell >?

Advice much appreciated .

all the best and thanks.

I was just going to start a new thread with a very similar problem. It started last week, and after I started my car at work, it seemed a little rough, but not too bad, then about 6 miles later while doing about 75MPH, the car starts to run rough, like going over bad pavement, then the CEL flashes about 5 times, then stays on. When the CEL stays on, the car is fine and back to normal. I went home and got out my code reader, and accidently clicked on "clear codes".

So today, after about 60 miles of everything being OK, the same exact thing happened. This time I got P0303, and P1315. I know that P0303 is misfire in cylinder 3, and P1315 is misfire in cylinder 3, emission relevant. I also just bought durametric, but I not sure if clearing with the cheap code reader, if durametric will still be able to pull up the codes.

My 99 996 has about 24K on it now, and has been working great. Could this a bad MAF, or o2 sensor?

Thanks!

[Loren]

Ok some background and maybe some pointers - Ie Am I OK to still drive.

here is the background -- Had the car three years (996 1999) No issues at all - done 25K miles had it serviced on the nail - Actually just had a minor service 400 miles ago ..

Drove the car yesterday did few hundred miles and drove to work today -- Came home Midday .. (left card outside - It has rained heavily)

So 6 hours after driving ie Car is cold - Wife goes to pick up daughter .. Comes home and says that light (the CEL) flashed 5x and then went solid -- Then she drove a little further and it flashed and went solid - Clearly I said if it flashed then YOU should not drive - Anyhow the journey was about a mile so I dont see a huge problem - Plus the light was Solid. Didnt continue to flash.

My symptoms are

Solid CEL

Rough Idle

So I pulled the wiring out of the MAF and disconnected the battery for 1 Min - Reconnected everything - Ran the car - No CEL everything seems fine. It runs just the same as it ever did - Nice and smooth - Power seems there - Engine doesnt feel lumpy like its throw a cylinder or anything really serious

Question --

Are the codes still there if I took it to a dealer .. Or its all gone as as Cleared it down .

Should I suspect MAF and or Coilpacks (ie car is now getting on a bit)

Final question - OK to continue to drive like this ? Temps and oil pressures seem just the same as always . The CEL is only related to Engine Air and fuel mix intake issues - Thats correct isnt it ? -

I know this question has been asked a few times - but I have been confused on the CEL light - Maybe it was dirt on the MAF or water in a coilpack . Is there any way to visually tell >?

Advice much appreciated .

all the best and thanks.

I was just going to start a new thread with a very similar problem. It started last week, and after I started my car at work, it seemed a little rough, but not too bad, then about 6 miles later while doing about 75MPH, the car starts to run rough, like going over bad pavement, then the CEL flashes about 5 times, then stays on. When the CEL stays on, the car is fine and back to normal. I went home and got out my code reader, and accidently clicked on "clear codes".

So today, after about 60 miles of everything being OK, the same exact thing happened. This time I got P0303, and P1315. I know that P0303 is misfire in cylinder 3, and P1315 is misfire in cylinder 3, emission relevant. I also just bought durametric, but I not sure if clearing with the cheap code reader, if durametric will still be able to pull up the codes.

My 99 996 has about 24K on it now, and has been working great. Could this a bad MAF, or o2 sensor?

Thanks!

All the codes point cylinder 3 - I would check the coil pack and the spark plug on cylinder 3.

[OCNYPORSCHE]

Thanks Loren. I will check. Too bad that one is really tough to get to. Cylinder 3 is in the back on the driver's side. Here is the funny thing, this morning the car worked perfect. I had reset the CEL yesterday, parked it for the night in the garage, and then this morning it is totally perfect (or working normal). Could this just be bad gas? Maybe I should try some dry gas, but I hate putting anything in the gas tank except for gas.

[Loren]

Why would bad gas affect on one cylinder.

Sorry, if the codes always point to cylinder 3 - then something is wrong at cylinder 3.

[OCNYPORSCHE]

Loren, I agree. But from the P1315, the problem should be emissions related? So would that still be coil pack, or plug? Would a coil pack or plug be intermittent?

The car has been working great today. I also installed and ran Durametric, but I not sure how to read the O2 and MAF readings. Both banks seem to follow one another or match.

So I am thinking that it may be a dirty MAF or still bad gas. If it was bad gas, isn't possible that it could affect only 1 cylinder?

[Loren]

Loren, I agree. But from the P1315, the problem should be emissions related? So would that still be coil pack, or plug? Would a coil pack or plug be intermittent?

The car has been working great today. I also installed and ran Durametric, but I not sure how to read the O2 and MAF readings. Both banks seem to follow one another or match.

So I am thinking that it may be a dirty MAF or still bad gas. If it was bad gas, isn't possible that it could affect only 1 cylinder?

I have never seen bad gas cause anything but multiple misfires - never just one cylinder.

If it were my car I would change the coil pack and spark plug on cylinder 3 and see if the problem goes away. (Check the wiring on the coil pack connector too.)

[OCNYPORSCHE]

Hi Loren,

Which cylinder is #3. Is it the one towards the back of the car on the drivers side?

Thanks!

[Loren]

Hi Loren,

Which cylinder is #3. Is it the one towards the back of the car on the drivers side?

Thanks!