My new to me R53 JCW came with a P0341 code and ran like poo (would barely idle, started to smooth out over 3k)

Did some reading and tried the guess and check of changing both cam and crank sensor, code persisted. I pulled the valve cover and front engine cover off, rolled the engine around until I got the two links on on the crank sprocket and found that the colored link wasn't lining up with the mark on the cam sprocket....there was some weirdness though and that was the cam sprocket was on backwards. Reached out to PO, he told me valve for #2 had been replaced 20k before he sold it and likely happened then. I shrug and move on....

Car sat torn apart for a few weeks as I worked to get a house on the market (just in time for the V to kick the legs out of under the housing market...but I digress).

Now that my area is under lockdown I got back in the garage! I bought a compete Melling brand timing kit from rockauto, compete with sprockets, chain, guides and tensioner. Got it all installed and put the engine all back together, hoped in to turn the key and it cranked like no compression. Verified no compression with compression tester and double checked with a wet test too.

I dropped a reaching tool into #1 and cranked the engine around, it seems as if the crank is 180 out of time (valve overlap is happening near the bottom of stroke, intake valve opening with piston on a up stroke). I've pulled the front cover again and verified that my two links are on the crank marks and cam link is on the mark....WTF?! I visually compared the original sprockets to the replacements and the key ways appear identical in relation to timing marks. I have also done a leak down test with ~15psi and am able to roll the engine around and see the leakage change as valves close and the leakage drops off to 5% or so

I'm at a loss and am starting lose my mind as well! Any and all help is greatly appreciated!

stay safe and wash those paws!

 

Are you sure you're not 180° off on the Cam?
​​​​​Remember, the sprockets are different sizes and don't turn in a 1:1 ratio.
Pull the plugs to remove any compression and recheck the alignment of the timing marks with multiple rotations.

 

The cam gear only has the chain location indicator on one side. It should be facing away from the head/cam....so you can't get that wrong, unless???? If you use the tool to lock the cam/gear in the proper position and align the 2 lower links properly on the crank and 1 link on the cam gear...you can't get the timing wrong.

Just check all the above indicators and use the cam lock tool....easy peasy.

 

Yeah so that's one of the things...when I tore it down the original cam sprocket was on backwards! Yes with the mark facing the cam/valve train. I rolled the chain around numerous times until I sat down with the book, was even more confused and then finally for S/G looked from the back side...I texted the previous owner and he said he'll try and call at some point but i'm not hopeful that he will even have an answer.

After advice from a friend I popped the rocker arms off to try and find the "bunny ears" where the intake and exhaust lobes are pointing up but off center (TDC Compression) and with the crank at TDC that cam is about 90 degrees out from this. I'm convinced that some how this valve train is out of time (cam by 90 degree or crank by 180) but can't figure out how that happenes with keyed sprockets, intact key ways, timing marks I can see on the sprockets (not on backwards) and chain. Only thing I didn't do by the manual was the cam lock tool but with everything keyed I find it hard to believe the cam needs to be in the correct orientation for the tool to get the timing right

When I pulled the rocker arms I found excessive wear on exhaust #1 lobe (through the hardening and starting to pit) so I pulled the trigger on a new cam, which feels kinda dumb on engine with no compression but honestly hopping the cam is keyed different.

This car is a JCW, which should have a different head and this is an early model where supposedly the first owner took it back in after delivery and had the JCW package installed. Does any one know if this could have contributed to these shenanigans

 

It can't...I have the same setup...dealer installed JCW head.

You really need to start from scratch and use the cam lock tool. Even after using the tool, if you rotate the engine the timing marks will NOT line up for ??? revolutions. I did this when building an engine and it drove me crazy...I thought it had jumped a tooth....the cam link only moves like 1 or 2 teeth out of alignment/revolution.

Start over and check it all

 

Regardless of using the tool it takes quite a few rotations to get the marks to line up again, that's the way it is with marked timing belts as well.

Just rolled everything around again and with some patience I landed on the marks like I had set this morning. But watching the valve train and seeing the intake valve opening at the bottom of the piston stroke again doesn't encourage me to bust out the compression tester again. I don't think NAM has any option to upload videos so I can do that to youtube and link it shortly.

While I appreciate factory tools making life easier I don't feel this situation requires them, they are not used to set timing (like the timing tools do in my TDI) they are to hold resistance while you torque the cam sprocket off and on.

 

Open this in a new tab. Lengthy but it may provide some insight.

https://video.search.yahoo.com/video...kip=1585262607

 

I'll give it a watch shortly but I am look for more of a 1 in thousand failure than a typical how to. I feel fairly confident there is something not "normal" about this engine.

A sheared keyway was the best suggestion I got so far. I've visually inspected the face of the crank gear and the key looks as I'd expect but I might have to go back to the parts store and rent the slide hammer again, remove the new sprocket I put on and verify the keyway all the way down the shaft. I actually have another r53 that my buddy smashed last year and I'm going to get the engine opened open today and photograph timing mark orientations with piston @ tdc.

 

Top pic is whats in the new to me JCW, bottom is what came out the car my buddy smashed into the tree. I'll be happy to upload more pics but just trust me I have crank key way @ 12 o'clock (w/ crank timing @ 6 o'clock) in both pictures...defect or improper chain?

 

If the crank timing marks are at 6 o'clock??? Then it looks like the timing chain is screwed...almost looks like the copper links were installed on the wrong side of the chain. Lower picture looks correct/normal for these engins.
Pull the chain off the lower engine and compare them.

 

I've ran this past a handful of people and defect chain (link timing link in the wrong spot) is the best diagnosis so far!

Since the chain it self is new I'm tempted just to count links and sharpie in the correct link, with a know good engine (at least as far as cam orientation goes) I'm confident I can figure that out, swap in my new cam on Monday and rock it. I guess if this thing is off I'm super lucky it was off this much, I read somewhere the S motors will tolerate 4 links and the NA 2 links before bendys