Arne Klinge

Today when driving out of the driveway I knew something was not right. It felt sluggish and I could hear it did not run on all cylinders. So I got out had a listen and observed, then reversed back and shut it of.

1. I could hear and see that it was the Right side that was misfiring when standing behind the car. The right side exhaust had a bad beat and shaked.
2. There were no error message on the dash

Pulled out the Durametric and fired it up again. Then it It was running perfect, no misfire. But the Durametric said this:

• P0300, Porsche fault code 507 - Misfire detection (total)
• P0301, Porche fault code 508 - Misfire cylinder 1

Ok so I was right. Ran the car with actual values on misfire and rough running on all cylinders, no misfire and no rough running.

Lately because of unusually hot weather here in Norway I've been driving with all windows down and noticed that the right side of the engine clunks or ticks more pronounced than the left side. And today after the misfire issue, could not hear a difference between the two sides.

I've read about loose spark plugs, bad coils, bad gas, sticky valves and even bad valve lifters. Any thoughts?

Hurdigurdiman

change the lot. Plugs, coils and sleeves if you have sleeves on your model. You would be better removing the mufflers before the job if you are a DIY man. Save the skin on your knuckles.

Arne Klinge

Thanks for the reply Hurdigurdiman (nice nic), my car is a 2002 Carrera 3.6 so do not know if it got sleeves. Would very much like part numbers for, coils, sleves (if needed) and plugs.

Also have to add, the car had stood for about 5 days with very little petrol in the tank, and there has been very hot weather (above 30C). So maybe condensation could also be. A friend with a Boxter experienced this he said.

Hurdigurdiman

My advice would be to fill a 5 gallon can at the gas station and funnel it into your car and try it again. 93 octane. I don't think the 2002 has the sleeves. test for a spark first on each plug before you go spending on plugs and coils as the coils are pretty expensive to change if not needed. Pelican Parts coil $45 EACH X 6 = $270.. plugs about $10 each so you are looking at about $330 all told if you DIY. No sleeves required on the 2002 model.

Arne Klinge

Again thank you for your reply. Have filled it up with 98 octane, still no misfire. Here we only have 95 and 98 octane, the cars suggested fuel is 98 octane.

Find it peculiar the low octane found in America. There must be a performance loss due to that, are 3.4 and 3.6 listed with the same power output as in Europe? 301 and 320 HP respectively?

KoB

The US uses a different measurement for octane than is used in Europe. US octane numbers are typically several points lower than European numbers for the same fuel; our 93 octane gas and your 98 octane gas are likely the same stuff.

In the US, the 3.4 was listed at 296 - 300 hp, and the 3.6 was listed at 320 hp.

RDCR

Who sells 93 octane in Cali? I can only find higher octane at at the track and dedicated VP stations around here and that's all race gas.

Regardless of measurement differences I'm sure your 93 and 98 octane is better then the stuff they sell around here!

Arne Klinge

Did three test runs since the misfire with the Durametric attached. One after work, one later in the evening and one cold start this morning. Varied pressure on the fun pedal and speeds. No misfire at low or high RPM, low or high speed or idle. No rough running, it just works as it should, perfect. How could this be.

I have noticed one thing [as mentioned above], right bank (cylinders 1 to 3) had an extra clunk or tick, not quite a ticking sound but rhythmic in nature, is now gone.

Could it be some gunk or clutter was stuck in bank number one and eventually produced that misfire which got flushed out of there? Or is this just wasteful use of my imagination?

sjg1138

Coils can also be intermittent when they get old and fail. It could be that a coil is on the edge of failure.