Throttle response? Not MAF

[Alex Crow]

......Bizarre given the output of the sensor seems spot on - just goes to show checking with a volt meter isn't a great way to diagnose sensors (lesson learnt!).....

Indeed, you were probably using a digi meter as well.

As you have guessed, it only needs to glitch a value for a split second to log an issue.
Sounds like you have it sussed now, but do please let us know one way or the other.

 

[SteveX]

Received OEM sensor today, 2 min job to fit and it's fixed

Just recieved the new replacement tweeters, time to wire them in and my list is nearing the end!!!

Pick up the new locked tomorrow, clean and paint brakes, put new wheels on, get the tracking and alignment done and it's nearly sorted.

It's been a long few weeks.

Thanks guys

 

[PianoPaul]

You have added 2 and 2, and come to an answer that is not 4.

I will take a guess, a stab - fuel pressure regulation, possibly a pattern fuel filter has been fitted.
This is a guess, based on my years of experience working on these cars, but I will always test first, and replace that which is at fault when proven to be so.

The buzzing of the throttle body is correct, and I am sure the ECU and throttle position sensor do not deserve to be under suspicion, based on the information you have presented.

I have never yet had to replce a throttle body on a 112, can't actually remember the last one that I changed in fact, so it is some years...

What if you add intermittent metallic grinding horrible sounding noises to the buzzing, I've had a long handled screwdriver pressed on my ear listening and mine sounds awful/dire! and should it buzz so loud you can hear it 5metres away? I've got similar probs with my 320CLK doing about 13 to the gallon!

 

[SteveX]

What if you add intermittent metallic grinding horrible sounding noises to the buzzing, I've had a long handled screwdriver pressed on my ear listening and mine sounds awful/dire! and should it buzz so loud you can hear it 5metres away? I've got similar probs with my 320CLK doing about 13 to the gallon!

That doesn't sound normal, how is the throttle response?

 

[Alex Crow]

What if you add intermittent metallic grinding horrible sounding noises to the buzzing sounds bad, but hard to know without hearing it, I've had a long handled screwdriver pressed on my ear listening and mine sounds awful/dire! and should it buzz so loud you can hear it 5metres away? yes, with the ignition on and engine not running you can hear them buzz 5 meters away I've got similar probs with my 320CLK doing about 13 to the gallon!

Not up to speed with your problem as I type, but fault codes and further tests are the way to move it forward.

Throttle bodies rarely fail.
Throttle pedal sensors fail more commonly - we have an ML320 CDI in at the moment in need of one.