Hooray, new engine speed sensor cured misfire

[oxfordpaul 0]

Just thought i'd let you guys know, AMD have finally sorted a really bad misfire on my VR. Changed leads and coilpack to no avail ( although subssequently realised old coil pack was also duff so was adding to the poor running). Was told by one garage the engine was caputt which was just nonsense etc etc. Anyway, hundreds of pounds later, AMD changed the engine speed sensor and it now runs perfect. Thing is the fault was not showing on VAG.com unless it was actually misfiring (which it only did during warm-up??). Is this right or should the fault have been stored? Whatever, it's now all good again.

[Kevin Bacon 5]

It was definitely the engine speed sensor they changed (£140) then, and not the Cam sensor? Yours might have been losing it's resolution slightly but not quite enough for the ECU to throw an "Implausible signal" code. Generally speaking though, they either work or they don't, so your situation is quite strange but it sounds like the sensor was perhaps skipping a cycle or two during warm up which was causing the misfiring.

 

And a duff coilpack will only have worsened the effect too....

 

Glad it's all sorted.

[dr_mat 0]

I don't think I've ever heard of anyone reporting that VAG-COM shows up Engine Speed Sensor problems, to be honest. It's a bit pants like that, the ECU doesn't seem to be very good at diagnosing problems with that most important of sensors.. :(

I suppose if the cables were broke it would be clear, but in cases like this it doesn't seem to report anything useful.

[Kevin Bacon 5]

I've had to replace one because of a VAG-COM error actually. "Implausible Signal - intermittent". This basically means the output is intermittently lower than the specified voltage and the ECU detects that. "No signal" and "Short to ground" are the other 2 errors you're likely to get, certainly "No signal" everytime you connect VAG-COM with the engine off.

[dr_mat 0]

Well now I've heard of it. :)

[oxfordpaul 0]

No, deffo engine speed sensor, yes the dear one!! But also they said the loom to the sensor had been rubbing on the engine and the wires had been shorting out so i suppose this would explain the intermittent nature or just when cold and damp etc. It's a wierd one but thankfully sorted.

[fast x 0]

Nice one!!!! where abouts is the engine is the eng speed sensor????

 

cheers philip. and the 140 is inc vat or what???? and is this a dealer part????