Help!

[AMGeed]

^ Its the diagnostic trouble codes that will be displayed when having a test on Mercedes STAR diagnostic system.

You need an indy, with STAR, to do a proper diagnosis and act on the fault codes you see.

Sorry, you're in the wrong part of the country for me to know who to go to.

 

[JORDAN MAGUIRE]

I had it scanned other day at garage and only fault code thrown was a sensor in the exhaust system? But no engine management light

^ Its the diagnostic trouble codes that will be displayed when having a test on Mercedes STAR diagnostic system.

You need an indy, with STAR, to do a proper diagnosis and act on the fault codes you see.

Sorry, you're in the wrong part of the country for me to know who to go to.

 

[AMGeed]

^ That would be the oxygen sensor. Was it replaced?

When there is a fault, a code is recorded in the ECU, often without any management light being lit. Do a STAR test and all current and stored codes are revealed. Clear the stored codes, then test for current. Its a process of elimination.

 

[JORDAN MAGUIRE]

Yes the part has now been replaced and it has made no difference, hmmm also I started it up other day and was making a strange whistling noise but I stalled it trying to concentrate on the noise too much but when I started her back up it had stopped?

 

[Steve@Avantgarde]

It probably has a snapped inlet manifold bolt. Extremely common on the 651, throws up all kinds of sensors relating to the exhaust and induction system but usually there isa fault code with them that everyone either ignores or doesnt come up on the generic code reader which is "charge pressure differential - charge pressure too low" - meaning basically it has an air leak.

Had one from another garage this week where they had replaced pretty much every sensor under the bonnet they could think of just because thats what the code reader said.

The other thing you have to watch is the modified wiring loom for the exhaust temperature sensor. That will cause the DPF to fill too high causing limp mode. Again there is a modification kit for this as well as an updated sensor. The DPF will then need to be cleaned and regenerated to bring down its fill level.

I would find an Indie that could help you further as it sounds as if you are guessing a bit and getting nowhere.

 

[JORDAN MAGUIRE]

Dpf is long gone mate and it hasn't caused any more whistling noises and nor going into limp mode just really sluggish in 2nd gear? Yeah I've replaced a few sensors but not getting anywhere mate

 

[JORDAN MAGUIRE]

P.s what's an indie

 

[Steve@Avantgarde]

Indie - Independent specialist of MB vehicles!

Ahh so its been de-catted/dpf'd.

So now we know it must have a remap through the ECU. And that could be your problem. The injector rates could be all over the place. I have definitely dealt with issues like this before. Ask GAD on here, they are the ones who usually inspect the suspect remaps for me.

 

[JORDAN MAGUIRE]

Who is GAD? And how would i be able to check the injector rates? It's only 2nd gear causing the issues?

 

[Steve@Avantgarde]

GAD tuning are forum members here and excellent map specialists.

But I would start with the fault codes first and process them properly.

 

[JORDAN MAGUIRE]

I've got it booked to have a look at the map soon and there are no stored codes on the ecu

 

[LostKiwi]

I've got it booked to have a look at the map soon and there are no stored codes on the ecu

When you say no codes stored what are you using to read codes? Not all readers interpret all codes and report them. That's why we bang on about Star - if there's a code it will report it.

 

[JORDAN MAGUIRE]

Well I've been to 3 different garages to use there code readers

 

[Steve@Avantgarde]

Have you actually used a Mercedes specialist to use STAR?

 

[JORDAN MAGUIRE]

Is there anyone with the STAR package around Doncaster area?

 

[JORDAN MAGUIRE]

Been to mercedes no faults brought up! At a loss now