raineycd

Oh and reset your ECU - make sure you have your radio codes, then disconnect your neg battery cable for 30 minutes, then re-connect.

Edrtith

When did you last change your plugs?

judd944

plugs were changed at 22k I found out by calling the last dealer that serviced the car. It has been more than 20k miles with 10k running a higher boost tune.

sounds good, I will put the bumper back on and run it without the rear bumperettes to save weight during the test drive. it will be getting a new fuel filter as well.

judd944

boost leak test? have a link on a DIY for that that Chad? is it just checking all the hoses to make sure they are all connected and not dry/brittle?

judd944

Got it done last night. Car drives wonderful and seems even smoother than I recall!

Looking forward to taking it to Keeneland Concours tomorrow !

I also replaced the coils based on everyones advice. the old ones looked great but were 996 part numbers so I upgraded everything while I was in there.

Carlo_Carrera

Where in the exhaust system are the wideband O2s?

Macster

The #1 O2 sensors, #1 referring to the sensors just ahead of the converters. Wide-band sensors are used to allow more precise control of the fuel mixture.

Carlo_Carrera

Thanks, so replace these O2s at around 50k.

When should the O2s aft of the cats be swapped out?

PelicanParts.com

Good deal! Have fun at the concours!

Mark/Pelican Parts

judd944

Misfire came back 8 miles from home.
Same issue as before

Macster

Well, that depends.

Let me elaborate.

First I've never had to replace these in my Turbo. When will I? When they signal they need to be replaced with the appropriate error codes or the engine exhibits some behavior that is clearly tied to these sensors needing replacement. I'm not sure what that behavior would be. I do not think it would be misfires but I might be wrong.

Second, now even with no error codes signaling the sensors are going bad or have gone bad some advise replacing these after so many miles.

If you subscribe to the replace the sensors after so many miles line of thinking I would think you would replace all 4 sensors at the same time.

Macster

Misfires at all 6 cylinders?

Have you any data logging going on before/during and the misfires? I wonder what the short term fuel trims, timing advance, and MAP readings are?

Kind of a long shot but is the fuel filter reasonably new? This was mentioned before and I do not know if there was any followup.

Anyhow, I think you had better do more than just look at the intake system for a boost leak. You need or you need to have someone do a real test for intake leaks.

Also, you might consider having the engine checked for proper operation of the VarioCam Plus system. Not the valve timing portion but the low/high lift portion.

IIRC this involves a road test with a tech driving and one operating the diagnostics computer observing O2 sensor readings.

Carlo_Carrera

That is a kick in teeth. Sorry.

I think Macster is correct you might want to consider professional help. It might be something very small but you may need full diagnostic gear to track it down.

It sounds like some sort of electrical problem, as in the ECU is not getting proper readings from a sensor or an electrical unit has failed and is not responding to the commands from the ECU. There are a ton of electrically controlled units on these cars.

judd944

Just read the code. Misfire 1-3. Tech will check it this week.

judd944

New fuel filter installed this morning. CEL with misfire after 10 min of driving. I have not checked the code but I am guessing the misfire is on 1-3