XC70: Engine Advice needed. EGR, boost sensor, MAP sensor all faulty?

[green van man]

I had no end of trouble with the works Mercedes sprinter being diagnosed with generic diagnosis machines, in the end it went to Mercedes in Swansea on a truck, they had it 10 days, 30 minuits after I picked it up the fault re occurred. Mercedes had it back for a further 5 days in which time they fitted new erg valve and inlet manifold before it was fixed.

Not trying to depress you but a couple of things I learned from the episode.
1 you need the correct test equipment to do the job fully
2 that correct test equipment needs to be operated by someone whom knows what they are doing.
3 once you find such a place you stick to it.

As I said it was the works van and while inconvenient I was not paying the bill, it was a considerable bill by the end though.

Paul.

[Ajayne]

Thanks for all the replies. The car is a Volvo XC70 2.0 Diesel Drive Edition SE Lux. So the garage said that they couldn't find a fault with the MAP sensor and they suspected the turbo. This was then sent away to be cleaned. They then said that they had completed all the work but that the warning light would come back on after 50 miles if there was still a problem. Sure enough, it did.

So that's a new EGR ( I can see that), a clean turbo and supposedly clean sensors but still the emissions light comes on. I asked for an itemised list of what they have actually done but as yet, I haven't received one.

I have contacted the dealer and told him that I'm not happy driving up and down the M1 to his chosen garage so now he is coming to pick it up to fix it or refund. I'm happy with that and would prefer to keep the car. However, I'd appreciate any advice as to whether this is going to give me problems in the future.

[AndyV7o]

Who knows... It could be an electrical gremlin which are hard to trace, it could be ecu, it could be dpf...
We had a vivaro, both service and eml light came on, code to do with throttle pedal, corrosion on a multi-plug, still stayed on, now it said glowplugs, those were done, still stayed on, no fault codes present or pending via decent diagnostics (snap on or similar) or Opcom (cloned dealership diagnostics like vida etc) nothing, everything tested, no probs found, neither would clear, it totally ignored all pedal/ignition reset dances (I spent hours).
We sold it before we ever got any further, just said theres nothing wrong, showed garage reports, offered to put on opcom and go through everything from engine, through abs, steering, lighbulbs, stereo, etc to prove everything is fine.
It must've been ecu. Drove faultless, emissions faultless, mpg great, etc etc...

Thus if dealer cant find anything at all wrong with it, in view of current mot rules, you might be best to walk away unless dealer is prepared to go as far as replacing ecu, spending hours poking away at the loom, etc without charging you...

[Tatsfield]

I thought any warning light on the dashboard failed the MoT.

[AndyV7o]

It does now, hence my statement about 'current mot rules', previously it was similar but if eml was on and vehicle passed emissions it could be passed (was told this by an mot tester), now it cant.

[Ajayne]

I suppose you could reset the dashboard warning light through the obd2 just before it went in for the MOT. It's mystifying, according to the garage they changed the ERG, stripped and cleaned the inlet system, replaced the MAP sensor and DPF sensor,cleaned the turbo, carbon cleaned the engine and reset the ECU. If they are telling the truth then that should have dealt with all the problems signified by the diagnostics (if they read that correctly). I would prefer it seen by a Volvo specialist but it is up to the dealer where he takes it. If it's not fixed this time I'll get my money back and look for another car. Pain.

[AndyV7o]

Electrical gremlins.....