W169 Safe/Engine probs

[John Sessions]

Hi folks - latest in the line of probs with this car....

Engine fault light was coming on/off intermittently. Code reader - no faults. eventually stayed on, but everything fine - still no fault on the reader.

Then started doing the dreaded 3k max intermittently. Always cleared on start-up at any time. Changed MAF as obvious candidate.

Now runs for 5 mins fine, then 3K max. Turn off/on again, runs fine 5 mins, then goes again. And on and on.

Already checked for obvious air leaks etc, nothing. Makes no difference if engine hot/cold.

Any ideas anyone?

 

[BlackC55]

You need it checked on a Star.

 

[John Sessions]

When I say "fault reader" I mean Star. No faults.

 

[BlackC55]

If the engine light is on there must be codes.

 

[John Sessions]

If the engine light is on there must be codes.

So you would assume, but there aren't. Which is why I left it alone the first time, assuming there was a fault with the fault system - which would be pretty much in line with this car and all it's problems. And of course (I don't have a reader) at £70 a pop at the dealer (+v.a.t) just to plug it in, and little less and any Star-equipped indep round here, it's not something one wants to do again and again! Each time it's reset, it stays off for a couple of days, then comes on intermittently, then stays on - useless. Does this independently of what the engine's doing in terms of faults.

I'm prepared to have a go at the other "usual suspects" - EGR, TPS, CPS, rail pressure etc, but wondered if the symptoms are familiar to anyone before I just fish around blind. I'm hoping it's not EGM related or it's going for scrap!