Bent connecting rod. 2019 VW 2.0 bi-turbo (MAN TGE). Big update!

[JFWerkstatt]

Hi everyone, thought I’d do a post on my current findings.

2019 MAN TGE 2.0 bi-turbo 180bhp. The vehicle was misfiring up to around 1600rpm. After this it seemed to run fine.

The below video has a description of what’s been done so far, I’ve also fitted a pressure regulating valve with no improvement.

I’m on the fence whether to do a compression test now as I know cyd 1 will be significantly lower than the other 3 due to the lesser stroke meaning less travel to compress the air fuel mixture. Cylinders 2 and 3 are identical heights (cylinders 1 + 4 and 2 + 3 are paired in travel through the combustion cycle (Otto Cycle which refers to the characteristics of a gas when compressed - suck, squeeze, bang, blow).

I have yet to view the bores and the vehicle is not noticeably losing coolant.

Hopefully this’ll shed some light on the internal workings and document further findings, processes and fix for this issue.

This engine and gearbox have to be removed to strip and rebuild due to it being a rear wheel drive.

Cheers, Josh/JF Werkstatt.

 

[DXX]

Lumpy T6 - Triggers Broom! Misfire & Vibration under 1500rpm.

Hi All, I have a 2018 T6, that I'm running out of patience with... and garages... So I have purchased VCDS to try and get to the bottom of it... First issue was it started to use coolant, I swapped a known good charge cooler to eliminate that, Max to min in around 100 miles, So took it to VW...

www.t6forum.com

 

[bluezie]

Definitely engine out and strip down. Almost certainly a bent rod, unless the engine was loudly knocking, then it could be a big end bearing.
It doesn't take much coolant to hydrolock and engine, and it could also be a faulty fuel injector.

 

[JFWerkstatt]

Definitely engine out and strip down. Almost certainly a bent rod, unless the engine was loudly knocking, then it could be a big end bearing.
It doesn't take much coolant to hydrolock and engine, and it could also be a faulty fuel injector.

I’ve had all 5 injectors tested and all came back good so I’d imagine it’s the cooler, we will see in the coming days! I’m actually excited, I really enjoy these big jobs.

 

[JFWerkstatt]

 

[JFWerkstatt]

The strip begins, genuinely excited to get this one ripped apart and find the cause of the bent rod. Will keep this thread updated with progress and pictures along the way.
Hopefully this’ll save a few future rod benders some $$ because I read someone the other day had spent £4500 at 3 garages just to find he had a bent rod. This diagnosis so far has cost about £500 however, that includes getting 5x injectors tested and a new seal pack plus cylinder head cover gasket.

 

[JFWerkstatt]

Can’t lie this has been a pig, give me a transverse engine any day of the week
Anyway, the actual engine strip starts tomorrow. For anyone stumbling across this thread, bring the technicians some painkillers and beers once the job is done - back is ruined and I’m clucking for a Corona now

 

[JFWerkstatt]

Right so I’ve stripped her down. Hopefully you’ll enjoy these pictures as much as I did stripping (usually a weekend thing for me).

Firstly I got her on the stand and drained the oil.

Then I removed the EGR valve and cooler (believed to be the culprit of the damage).

Next off was the coolant manifold - or at least that’s what I am calling it. Second picture is the EGR valve, cooler, manifold and associated coolant lines that didn’t stay with the van.

Engine was timed to TDC.

Bi-turbo unit was removed, it was not split to save a few $$ on gaskets. Interestingly, the 4 nuts/studs on the front of the engine (timed face) were all hand tight - I wonder if we’ll see offices with blown manifold gaskets in the future ((he says this as a EU6 T6 has been dropped off today with a decent exhaust blow - yet to be diagnosed other than audibly))).

HPFP and inlet manifold removed.

Cams housed in the cam cradle removed.

Rockers/roller bearings removed and bagged up. Head bolts removed in the opposite sequence they’d be torqued on application.

And here’s the money shot, taken from the GB side or back of the engine. Cyd 4 visibly protruding while cyd 1 is recessed below the machined face of the head. 2.xxmm lower according to the initial diagnosis when the engine was fitted.

In the video link above there is a sneak peak of cylinder 1 bore. Doesn’t seem unsalvageable but, after discussion with the customer I believe we’re going down the new engine route as there are so many items that would need replacing if the engine were to be rebuilt/reconditioned.

 

[DXX]

In dealer world it would be; piston / rod / DPF backflush / Autotrader no doubt.
Good diagnosis, given how many premature failures are caused by EGRs it’s hard to see how the environment is benefiting.

 

[Cool Carlos]

Nice work Josh @JFWerkstatt

 

[JFWerkstatt]

Today we have ordered a short block, head gasket, EGR cooler, all gaskets associated with removed components, cam cradle sealant, timing belt kit and some other odds and sods. Delivery due on Wednesday.