how do you test the Ignition control module besides swapping cables?
 

2001 allroad 2.7T


codes are p0300, p0301

I bought 6 new coils, spark plugs are new, swapped everybody and their mothers around, checked for air leaks, still the same 2 codes

I'm perplexed...

spark is strong from the coil....connectors are measuring 30.2 volts on one wire while engine is running... number 1 cylinder, not sure which is positively no.1 but it looks wet in there when I removed plug...so tells me its not burning gasoline correctly

I found out that these cars have two Ignition control modules on airbox...

did the cable swap and now I get three codes...p0300 , p0301 , p0304

cylinder 4 is a new one... clear it and the same three come back consistently

swapped cables back to how they were and now only same two codes p0300, p0301

before I order expensive control modules at $180 each...is there a fool proof way to check these modules,besides swapping around cables... I do have VAGCOM scanner...

and why is cylinder 1 always popping up regardless which module? I thought only one bank is controlled by each seperately

and which one is cylinder 4?

ouch! one cylinder is only reading 60 psi compression test
 

just did a leak down test to the cylinder on the passenger side towards front of vehicle... it shows only 60 psi...

before I lose all hope and junk this nightmare of a car, is it possible that timing is off one tooth? not letting the valve close completely, or other possibilities besides a bent valve?

I did put a new timing belt myself by marking the teeth on the old belt and matching up the marks to the new belt and sprockets...

is there a way to test timing?

I can do timing, but I will not remove this head and rework it.

did another leak down test and it read 160! weird!
 

I am perplexed again. and I've torn these engines apart...and I learn something new always...

if I rev engine, it will climb and hold pressure.


funny,

p0304 disappeared now after a strong reving to red line...

only p0301 remains,
even if I switch cables around on Ignition control module code stays the same...

its like valve is staying open

Went for a very long country road drive.
The car shakes terribly at acceleration. Check engine light flashes while driving.
If I stomp the accelerator, she responds smoothly with power.
If I feather it around 60 mph shakes sputters.
Stopped clear codes and switch ignition control module wires and still the same identical codes p0300 and p0301 cylinder 1 misfire...
If idle, I can remove the coil and it's shooting a strong spark but that cylinder is not firing. I wonder what else to check. Compression scared me, at 80, but then it climbed to 180 when I came back from taking a break. If valve was bent , it would stay bent. It would read low even on acceleration.
I am trying to find out if one tooth off timing can cause valves on cylinder 1 to stay open. That spark plug is always wet when I pull it out.