Have VAG-Com. Now what to do? Misfire

[jjcsnlynn]

I have a problem in a 2000 NB Gasser (belongs to my neighbor). It will start up and idle fine when cold. After getting hot or driving 10 miles to get hot, it misifires. There is no loss of coolant or oil/water problems, so I don't suspect a head gasket.

-It started out with a P0304 - he changed the plugs
-P0304 returned - changed the coils (all 4 with the new style)
-Started getting P0300, p0302, P0303, and P0304- code kept jumping around and sometimes gets one, two or all the codes
-Later he got a Fuel Pressure code (don't know what code) so he changed the fuel filter and fuel pressure regulator - Ran fine for 20 minutes, he removed the battery for a charge and everything came back.
-I just took it to a friends house and VAG-COM is showing
16684
16688
16686 - these are the same as the P0300-P0304 codes with the scanner.

The VAG-COM showed the timing jumping from around 0 to as high as 14. I don't know if this is a symptom or cause. We disconnected the MAF and it didn't help.

After reading this thread, I'm wondering if he has a cam or crankshaft position sensor going bad or the flywheel. Any help would be appreciated.
Thanks in advance.
Jon

[Toad]

how are the vacuum lines?

[CrazyJames]

Merged and Edited...

[jjcsnlynn]

Originally Posted by Toad

how are the vacuum lines?

Vacuum lines were all replaced at the start of this. he said he was starting to have problems when he found them dry rotted, but they are all new or in good condition now.

I've pulled the MAF connector to see if it will run/idle any better. We'll see.

Anyone know anything about this VAG-COM? What can I check to tell me what is bad?

[sb_beetle]

If the spark plugs were replaced recently, make sure they are torqued to the proper settings 22ft/lbs.

[NBTurboFreak]

Originally Posted by sb_beetle

If the spark plugs were replaced recently, make sure they are torqued to the proper settings 22ft/lbs.

....Also make sure they were gapped to the correct distance.

[green02turbo]

does your car actually miss? Under a load or at idle? Give some drivability info.

[jjcsnlynn]

Originally Posted by green02turbo

does your car actually miss? Under a load or at idle? Give some drivability info.

Yes, when it's missing, it's missing at idle and driving. It seems to decrease at higher RPM with the clutch in.

I pulled the MAF connector the other day and he said it idled fine and drove 15 miles fine. Tonight it was back missing again. Found a large vacuum hose to the intake with a crack underneath. I think it's the PCV valve or something. We'll change it, check the plugs and go from there.