New to me, N46B20 - with problems

[TT Tim]

Hi All,

Newbie here, I have been playing with cars for many years, but have only recently purchased an E85 2.5, closely followed by a donor car E85 2.0.

the 2.0 was dirt cheap because the recovery service diagnosed it as having Timing Chain Failure. I spoke to the owner, she told me that it didn't have any noises prior to the failure, and that it just cut out and stopped.

At present it just cranks over and show no signs of life!

I have hooked it up to ISTA+ and had the following errors.







Can I have your thoughts please. I haven't done anything other that 'plug it in' so far.

Oh, did I mention it had £3K(UK) of engine work latter part of 2023, so would be a shame to not try and fix it.

Finally - am I right in saying that the N46 is a non-interference engine, so chain slippage, shouldn't cause valve train damage?

Many thanks

Tim

 

[enuff_zed]

I'm no real expert on these tbh, but firstly, the SIM undervoltage will be the airbag control module and possibly just due to a low battery.
The Traction Control fault code is probably just that the DME isn't getting enough info about engine performance and therefore cannot regulate engine power to assist traction.

So that leaves the two camshaft sensors.
Interesting that one says a negative short and the other says a positive short.
Got to be worth cleaning those plugs at least.

Could possibly be an issue with the DME itself though? Which is a pain because as far as I can tell that unit on the 2.0 cannot be programmed to ignore the EWS, as other engine'd cars can. So to swap the DME you end up also needing the EWS, then you add on ignition key, door key barrel, boot lock, glove box lock.......................

What engine work did it have done? Anything that was associated with the timing chain?

 

[TT Tim]

Thanks for the reply.

Had HG and new Chain in 2023.

The DME was being a bugger to start and wouldn't communicate with my Launch OBD kit, ended up getting it to communicate in ISTA.

What I'm puzzled by is that if it were the timing chain, I would expect some form of noise before it, of the guides failed - do you agree?

 

[enuff_zed]

Thanks for the reply.

Had HG and new Chain in 2023.

The DME was being a bugger to start and wouldn't communicate with my Launch OBD kit, ended up getting it to communicate in ISTA.

What I'm puzzled by is that if it were the timing chain, I would expect some form of noise before it, of the guides failed - do you agree?

I agree, but it's not too difficult to pop the top cover off and check it.
I think I'm leaning towards the DME if I'm honest.

 

[tug]

I was told in no uncertain terms that if the chain skipped a tooth it would be catastrophic for the N46 But have never heard of this ever happening. Also it would take something serious to make a chain snap which also has never been reported as far as i know. (i have researched the N46 for years having owned one for over 10 now)

Hopefully it is not as serious as that for you.

 

[colb]

Camshaft sensors would be my first go at fixing this looking at all the codes you have got. If either go bad it will cut the engine and fail to start as the dme dosn't know what position the engine is in.