1.8T Now Jerking/Joltint, DV fitment and PCV vented to atmosphere.

I checked injectors earlier and cylinder one was spraying but ill check again.

the fact its cured one misfire suggests the amp seems to be ok, the wires that have melted slightly come from the ecu. There is 3 wires so surely the damage would cause issues to all the cylinders or is my logic incorrect?

As you say, time to break out the multi meter and check for continuity etc

 

so far

I have continuity from each coil wire to its corresponding point on the 4 pin plug which goes into one side of the ignition amp. this is the side with the burns on it.

I also have continuity from the purple/black switch live coil to T10a pin 8.

I'm stumped with this now

 

yep that makes sense, I kinda thought there might be a chance a wire has attached itself to another but I chose not to believe it lol.

I will take the engine part harness out and unravel it..a pig of a job

 

ok stripped the loom down


no melts or crossing over, only damage is near the ignition amp plug...pics to follow






Old ignition amp

 

apart from the above, there are no visual defects or breaks in wiring.

An earth is exposed which I will tape up but I don't think this is the cause.

 

Tried a second working Ignition Amp and still has the same issue...

Tried a second ECU, the car is suffocating but I think cylinder one is firing, I will have to plumb everything back up tomorrow to see how it runs.

 

running on all four again...looks like a bad ECU. sounded sooooo much better.

Now can an ecu be repaired or is it not worth the time?

 

Thanks for all your help mate, I will stick some photos up later today once I've finished putting the mk2 back together

 

Car back running now but jolts forward when accelerating...might be another boost leak

When the car runs in limp mode, should I be able to hear to the waste gate opening and exhaust gasses bypassing the turbo? I can feel it coming off boost a lot sooner or does this sound like another leak somewhere?

 

None, i'll probably need to use measuring blocks now and compare to autodata..

I think its got two leaks at the moment, I know I forgot to tighten the outlet pipe.

its strange, it jolts forward with and without the maf connected, so its not that.

When the n75 valve is disconnected I can feel it come off boost a lot sooner but doesn't jolt then

sounds like another airleak?

Also the diverter valves, I think mine is plumbed incorrectly,

I have the charge pipe connected to the bottom of the valve and the tip connected to the side of the D.V. My understanding is any excess boost causes the spring in the valve to compress thus pushing air back into the TIP, hence recirculating air back into the turbo.

But when I look at oem pictures they are plumbed in the opposite way :S

Will the fact I have my catch can vented to atmosphere cause this, as its essentially measured air that's leaving the engine?

 

No longer jolting forward, the throttle body was cleaned, this has sorted the nasty idle and I think its sorted the car jolting.

I can still hear air escaping from somewhere :S, its an non silenced k03s so does anyone know if these things are loud units?

I also have a foul smell inside the cabin when the cars running :S like an oily damp coolant smell :S

 

Yep think the n75 valve is fine, it boosts to about 10psi before I run out of space.

The MAF is connected and the n75 from what I can see work fine, but I can still hear a massive air leak somewhere, its not as aggressive as it should be. If I go WOT it does spin but seems like there is more to come.

Re PCV valve, I thought maybe because the measured air is vented out by the catch can it could cause issues but I know if I connected the PCV to the oil filter housing and Cam cover port in a closed circuit, it smokes a lot. The venting to atmosphere has stopped this. Now that you mention it, the smell might be from the PCV system. Ill open the windows, boot and doors tomorrow to air the car out first.

Also I should really post this in the tyres/transmission thread but my tyres keep going flat quickly like overnight. I can hear air leaking from the tyre, I cant see any leaks but could a broken seal around the alloy/tyre edge cause this or is the alloy wheel knackered ie bent/buckled etc.