BEW misfiring when hot

Htnelson

Member
Joined
Feb 18, 2024
Location
USA
TDI
B1 passat BEW
My BEW has picked up a misfire when it gets to operating temp. It persists unless I really get on the throttle. I have VCDS and there are no codes being thrown but it does show an injector imbalance at idle on cylinder 3. Whats weird is that they are all within spec until it gets to operating temp. Then cylinder 3 slowly moves out of spec and the misfire starts.
It has 225k roughly and I just went through and replaced a bunch of parts recently. Including all the valve stem seals, tandem pump, set of injectors, turbo, and I got a 3 bar MAP.
The engine no longer has an ASV, EGR, or an intercooler.
It never causes it to shut off since its only on the one cylinder.
I have tested compression and they are all high and even on all cylinders. Cam and lifters look good they have definitely been replaced before my ownership.
I was fighting an oil/diesel mix pouring out of my exhaust from cylinder 3 before this and that prompted everything being replaced. The mix goes away at operating temp oddly enough and my oil level never really dropped so we marked it off as being mainly a DIESEL/oil mix when it was cold and decided to run it anyways.

But that is also where the misfire is originating. It shows as an injector imbalance at idle on cylinder 3.
Should I replace that one injector and see if it solves the issue? Or should I scrap this engine and try to catch another BEW coming up for sale?
The engine starts and runs flawlessly up until it gets to about 185 degrees and thats when it starts missing so badly.
I have a video of the misfire if needed
TIA
 
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