406oc.co.uk

Hi everyone.....my hdi 90 seems to have lost some of its power having to drop down gear on hills where I normally wouldn't. You can hear the turbo whistling when accelerating and feel it working but just seems to have gone flat after that. I noticed when under bonnet the other day that there was smoke coming from egr valve when reving it. I read that egr valve could cause lack of power so used a can of egr cleaner but also read that sometimes you need to remove the egr and clean properly. Could this be the problem as the cleaner hasnt helped. Car has just been serviced aroumd a month ago and has no warning lights on. Anti pollution fault appears from time to time but just goes away on its own. Any ideas thanks chris

As the EGR is connected to the turbo I would imagine that a leak at the base of the EGR would prevent the exhaust gases spinning up the turbo properly.

Get yourself some high temp liquid gasket and a blanking plate and take it out of the system all together. From other posts on here the ECU doesn't appear to mind EGR's being blanked without having to mess with the mapping.

Exhaust gases floating around the engine bay can make there way into the cabin so it do it sooner rather than later.

the problem i had was that my egr valve was bing forced open at high rpms ether way the way to fix this is to put a blanking plate in there

Have you checked the slack in the throttle cable? Schoolboy stuff I know but sometimes over-looked. If this is okay then I would suggest checking or replacing the air and fuel filters next. Then go about removing, cleaning and refitting the EGR to see if it is the problem, if its fixed then blank that baby off next time it plays up - no point cleaning it then taking it off straightaway...
If the car still feels a bit sluggish after cleaning the EGR then the next thing to check is the MAF ( try to borrow one to test first - 90's are a different part number to 110's - if yours is faulty then buy genuine Siemens one as much better quality.. )

I'm trying to suggest the cheapest options first....

Throttle cable was a bit slack so tightened up a notch. Fuel, air and oil filters have just been done not long ago. How hard is it to remove egr, clean then put back together. I have disconnected the maf sensor and been for a ride out and still the same. Could I blank it off and if car regains power could I then take off and clean or would I need to clean it up first.

If you have disconnected the MAF and nothing changed, does this mean your MAF is broke....? If it was working then you would notice a difference when you unplugged it, albeit better or worse..?

I haven't done my EGR, it was done for me, but there is a 'how to' on the forum somewhere, either this one or the 406 coupe club, and plenty on here have tackled it themselves.

Seen a video of a pug with broken maf on youtube car was very sluggish and when maf was disconnected restored all power to car when mine was disconnected nothing happened. Ill try blanking egr first off and go from there thanks again

You can have a dead maf which will behave the same as unplugging it or a bad maf where unplugging it makes the car better. The power difference between a good maf and unplugged will be noticeable.

Cheers ollieNZ will order a new maf soon as I can. Thanks again