AMF misfire

Looks straight forward thank you. Ill check out my version of VCDS, I’ve got the lite version, I suspect it won’t do this check.
Lite does do it, but you need to get it licensed by Rosstech, (via their website), cost is $99.
That gives you a license for one laptop, unlimited VINs, and one laptop change. Ebay KKL lead is fine.
Mac.
 
The car has stopped misfiring since the weather became cold. Does this suggest anything to anybody?
Consequently I've not progressed a diagnostic licence, what difference could the cold make?
Thank you.
 
The car ran OK then recently I decided to put a drop of low ash synthetic two stroke oil in the tank. It has liked this treatment in the past running smoother and quieter. The same day the weather warmed up. The car has refused to accelerate since and has been a danger to drive. It misfired gently and put on speed slowly. At idle it was fine and once up to speed it held speed without any problems. I decided to go back to basics.

Step 1 put some fresh fuel in. I had half a tank that had been in for moths so I filled up. No change.

Step 2 check the service records. Both fuel and air filters are on a 40k mile schedule for replacement. My filters have done 33k miles but I decided to replace them starting with the air filter. Car runs smoother but still misfires.

Step 3 drain the fuel filter. A very small amount of water my have been in the fuel but by the time I got a jar under it only clean good diesel was dripping out. No change.

Step 4 replace the fuel filter. Misfire gone, car running nicely.

A bit black, but I didn't think too bad, The bits in the drip tray is just general muck off the underside of the car:

IMG_0579.jpg


I think I will put filters on a 30k mile schedule for replacement.

10/10 to @audifan , got this right almost a year ago.
 
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I've had my injectors checked by Darwen Diesels. They are good and balanced but on bottom tolerance for fuel delivery. I'm not entirely sure what that means in terms of misfire (probably nothing) but I think it helps explain why I get good emission results at MOT. Also possibly why the car needs driving hard to get it to move.
I'm going to conclude that the initial failure and misfire was caused by the harness. More recently a prematurely blocked fuel filter restricted fuel flow. I also have bore damage and head damage which probably hasn't helped the combustion process but my conclusion right now is two misfires first due to harness failure second due to blocked fuel filter.

Edit. I may come back to this thread if I find turbo damage. A fair amount of metal (bits of glow plug) has rattled around in the cylinders and must have excited via the turbo. The turbine could be compromised.
 
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Wow this just keeps on going, do you now need to fit a new head then? Saw one in Swindon on flea Bay with injectors recently. No affiliation.
 
@CrispyEdd I’m undecided at the moment. Ill try and get some better views of the damage before I put the injectors back in. I’ll run it until suitable substitute parts show up.
I just need to be patient. I don't expect any problems getting the major engine components I need. With clean air zones becoming more common I expect used diesel engines to be plentiful in the future.
The cam shells were planned to be my last major job before I’m not allowed to drive it anymore. Now I potentially have an engine swap and this is the first time an engine I bought new has not out lasted the car. A bit disappointing.
 
I've got a head on the shelf from a 105k mile engine if that's any help.
That's tempting low miles but iI think I'm going to need a head and a block. The bores on No1 look like this:

A2 Head 26.JPG



Piston Crown like this:

A2 Head 25.JPG



Underside of cylinder head like this:

A2 Head 32.JPG



Cylinders 2 and 3

A2 Head 22.JPG


A2 Head 23.JPG


A2 Head 24.JPG
 
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I've inserted all of the pictures I uploaded, see above. Yes I think is probably best refereed to as ducked :(
Really uncommon for the TDI engine to go like this. I've seen cylinders on cars with 250k plus still look super smooth and brand new.
 
Really uncommon for the TDI engine to go like this. I've seen cylinders on cars with 250k plus still look super smooth and brand new.
It is a victim of the ECP, GSF Halfords data base error. I was supplied with 5v glow plugs before the problem was reported on here. The damage is due to melted glow plugs.

A2 Head 29.JPG
 
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Found something else that could contribute to smoke on starting and could contribute to misfire? Lower most O ring sealing the combustion chamber from the pressure rail fed by the tandem pump. Or perhaps not there is a further brass washer; anyway it is not good and will have been leaking:

A2 Head 33.jpg


New seals and washers fitted.

A2 Head 35.jpg


Fingers crossed for no misfires until I find a replacement engine.
 
Found something else that could contribute to smoke on starting and could contribute to misfire? Lower most O ring sealing the combustion chamber from the pressure rail fed by the tandem pump. Or perhaps not there is a further brass washer; anyway it is not good and will have been leaking:

View attachment 104051

New seals and washers fitted.

View attachment 104052

Fingers crossed for no misfires until I find a replacement engine.
Hi Phil,
I thought the same but have you measured the thickness with a mic or vernier to confirm?
If you look at the new washers you’ve fitted there’s a very faint mark in the middle of the edge I think.
Cheers
Keith.
 
Hi Phil,
I thought the same but have you measured the thickness with a mic or vernier to confirm?
If you look at the new washers you’ve fitted there’s a very faint mark in the middle of the edge I think.
Cheers
Keith.
Hi, no I never bothered to measure the new brass washers. Being branded Bosch I assumed they were correct.
However if they are slightly thinner or thicker they should still clamp up and seal. A different thickness washer would reduce the life of the new O rings because they could contact with worn patches on the cylinder head no longer corresponding to worn patches on the injectors. Darwen Diesels did say worn O rings result in extra diesel in the combustion chamber. Perhaps the pressure is sufficient to lift the injector fractionally and break the the brass washer seal?
 
I can confirm my misfire has gone, despite the cylinder and piston damage the car is running well. There have been three contribution factors to my running problems:
Injector harness
Clogged fuel filter
Injector seals or possible injector setup issues.
Edit, I forgot one other change that could have helped. I cleaned the MAF. If you decide to do this there is a special MAF cleaner. Google advised me carb cleaner, brake cleaner or mechanical cleaning will ruin your MAF.
 
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