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listerjones

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Location
Brighton
Car
2.2 CDTI Sport
Cdi accord, full service with genuine parts. Car still doing about 29-30mpg. There is a fairly strong unburnt diesel smell outside, nothing inside. Flat spot when accelerating at around 2100-2500 rpm. New maf on order.

Anyone know any common issues regarding mpg or flat spots on these motors?

Thanks in advance.

All vacuum hoses replaced as well.

No fault lights on.
 
I know you think you've fixed your EGR but you haven't. You have an egr leak which is altering the AFR as there is unexpected air entering the inlet the ecu isn't expecting.

The slight hesitation is also your egr and possibly IMRC sticking.
 
Yeah that's definitely plausible bud. Also I've been thinking since you mentioned it a little while ago whether someone has been messing with the ecu mapping. I just don't know how these cars drive as this is the only one I've ever driven.

Maybe a remap and delete is in order.

I had thought about imrc valve too but that doesn't look like it would be happy to be taken apart.
 
It's the single biggest cause of poor running issues on these cars in my experience (apart from the usual non genuine or old fuel filter issues).

You may get away with not cleaning the inlet out but personally I would look at doing the whole job. Remove the inlet and throughly clean and free up the flaps ensuring they move freely. And then blank the egr and map it out with stage 1.

You will not recognise it as the same car after that.
 
Generally through my career I've just repaired cars, not tuned and mapped them. What is stage 1 plus delete like for mot smoke test?

I agree egr are the main reason on modern diesel problems, so very tempting to get shot of it.

How much can the clutch on these things comfortably handle then bud,
 
With a physical blanking plate in place, they are fine for smoke, no issue at all.

Clutch is definitely something to think about, done plenty on stock clutches without issue but then some can have an issue due to weak pressure plate springs.
 
How strong are the dual masses on these, made of chocolate on early minded common rails. Hoping Honda are a bit stronger.

What sort of mpg on stage 1 then bud.
 
DMF failures on these are relatively rare. Real problem is with clutch pressure plate
 
New maf fitted and flat spot and smell has gone. Need to see how many miles it does to work out mpg.
 
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