307 loss of power

[Nelly1]

Morning all and sorry if this has been covered already but I couldn't find anything.
I've had my 1.6 hdi 307 for about 6 months and love it. Last week before a long drive to Scotland I treated it to a new auxiliary belt as the old one was frayed. Drove it away from the garage and instantly noticed a huge drop in power, took it straight back to the garage who were instantly on the defensive "it's nothing we have done" etc... I was told it's probably a bit of carbon stuck in the egr so fill the tank add some diesel magic and take it for a good drive. Tried that and no change. I have also noticed that the exhaust seems to be blowing a little too. Any advice on what to look for or check would be greatly appreciated. Like most I can't afford a huge bill from a garage that have replaced half the engine and still not found the fault.
Thanks in advance and sorry for the essay

[RichardW]

Welcome!

Don't worry about essays, we like that sort of thing....!

I would ask them exactly how they fitted the aux belt - it's likely that it is fitted with a stretch belt (mine is - looks like we have the same car combo!), and turning the engine backwards during fitting is a bad idea. Have a read of this thread: https://www.frenchcarforum.co.uk/forum/ ... 6&p=323069 Given that you suffered an immediate loss of power, cam timing has to be the first place to look. A decent diag session might throw something up, but not if the second cam timing is out. They might have snagged the vac line to turbo I suppose.

[Nelly1]

Thanks for the advice, I guess I'll have to get it to a garage as it doesn't sound like something I could do myself. I'll report back when I've had it checked

[Nelly1]

Update
I've had a full live diagnostic check done, I'm told the problem is the dreaded EGR valve. It's being replaced latter this week at a cost of £££ I'll let you know if it solves the problem

[ekjdm14]

Whereabouts are you located? It may be that one of us has diagbox and could check for any codes or issues with cam/crank sync.

Edit, just seen you've beaten me to it lol. Whereabouts did you have the diagnostic done, same garage? Seems funny this would happen in between the aux belt being changed, I don't suppose it's possible that a vac line or wiring to the egr could've been disturbed is it?

[Nelly1]

Definitely not the same garage. I was a bit more selective this time ( lesson learnt). Your right though seems very odd it happened when the belt was replaced, unfortunately as I'm pretty useless mechanically wise I have to trust the experts. Fingers crossed he sorts. I'll have found a garage I can trust and he'll get a happy new customer, and I've already got his next job lined up new turbo on the ex's C4

[ekjdm14]

Haha, sounds like you and Richard are both vying for the title of "1.6HDi central"!

If you do have them replace the turbo on the C4 (and it is also 1.6HDi as I've guessed) then be sure to have them check/clean/replace the oil feed to it and the vacuum pump, remove the strainer in the turbo feed and clean the oil pump gauze as appropriate to ensure the new turbo lasts.

[Nelly1]

Thanks for that I'll be sure to pass it on.
I'm sure I'm one of the worst 2nd hand car buyers there is
I do have a current love for French though

[Nelly1]

Update
EGR has been replaced, and surprise surprise the problem still exists. Garage is now saying ECU is not sending out the 5v required to operate the EGR. He's saying the ECU needs to be sent for test/repair so my questions are.

1) does this sound feasible or not
2)as an electrician I test voltage to equipment before I say it's knackered do mechanics not do this or do they just rely on the diagnostic equipment
Thanks in advance for any replies

[EDC5]

That sounds bad, surely they would have tested the feed to the EGR before replacing it? Could you try blanking the EGR off temporarily to see if that solves it? I'm assuming the EGR is stuck open?

What exactly is the loss of power like, is it low down in the revs or high up?
Is the engine warning light on?

[Nelly1]

No engine lights on at all, and it's a complete loss of power it's like it's constantly 40-50% down. It's almost like the turbo isn't working but it is. Think I'm just going to take the £300 loss on the EGR and park it up. It's not worth chucking a further£300+ at it

[EDC5]

If the EGR is stuck open then the exhaust gas that should be flowing to the turbo will not reach it. For the sake of £3 it might be worth it?

http://www.ebay.co.uk/itm/EGR-Blanking- ... Sw9OFZJYx0

Think that's the right one for your car. if it fixes it then the issue is with the EGR and it should be rectified.

Otherwise you might have a big boost leak. Very odd that no warning lights are on though with that much loss of power which leads me to suspect the EGR stuck open rather than the turbo or sensor issue that would normally cause a fault light.

[Nelly1]

The EGR has been replaced but there now saying it's a fault with the ECU as well as the fault with the EGR

[Nelly1]

I see what your saying sorry. Blank off the EGR and the lack of signal from the ECR doesn't matter.
Thank you I'll get them to give it a go

[EDC5]

Yeah, the ECU might be telling the EGR to open fully wide, might be worth mechanically blocking it with the plate just to see if it helps?