EGR Valve Question

[fizzwheel]

Our Maverick has been behaving strangely, rough idle, doesn't seem like it had any power and was sluggish pulling away and gave what felt like a misfire.

I've done some reading about it and I spoke to my brother who is a mechanic and he also asked his mate who worked for Ford whether it would be an issue with the EGR valve either sooted up, broken, or just failed.

Seems like that the symptoms its got all relate the EGR Valve and the Ex Ford Mechanic said it was more than likely that.

I've put a temporary bodge into place as recommended on the difflock forum into place where I blanked off the vacum feed into the EGR Valve and taken it for a test drive.

The lag and sluggish feel has gone from it and it whipped up to 90mph without to much trouble, so it seems to have resolved it.

Question I have is, will it do any damage with the EGR Valve disabled like this. I have seen a lot of people recommend removing it and blanking the valve off completely.

As I understand it, its function is to re-circulate exhaust gas back into the inlet so burn off unburnt fuel and also the exhaust gas being re-admiitted cool the charge into the cylinders which also helps promote cleaner exhaust gas as well.

Its a 2.7 Tdi engine, basically its a Nissan Engine with a ford badge stuck on it...

[yorkie_chris]

Oh a diesel problem clearly diagnosed and solved, how novel!

As far as I know the EGRs function is merely environmental, should be fine leaving it off.

[andrewsmith]

Eco measure (not a good one if Wiki is to be believed). You may get a engine issue light if its sensored. Maybe interesting a MOT time (emission tests)

Originally Posted by http://en.wikipedia.org/wiki/Exhaust_gas_recirculation

By feeding the lower oxygen exhaust gas into the intake, diesel EGR systems lower combustion temperature, reducing emissions of NOx. This makes combustion less efficient, compromising economy and power. Diesel EGR also increases soot production, though this was mitigated in the US by the simultaneous introduction of diesel particulate filters.[6] EGR systems can also add abrasive contaminants and increase engine oil acidity, which in turn can reduce engine longevity.[7]
Though engine manufacturors have refused to release details of the effect of EGR on fuel economy, the EPA regulations of 2002 that led to the introduction of cooled EGR were associated with a 3% drop in engine efficiency, bucking a trend of a .5% a year increase.[8]

There's a good explanation on here
http://fleetowner.com/management/feature/scr_egr_0701/

[fizzwheel]

Not to worried about it come MOT time as we are going to sell it shortly once we have found something to replace it with that doesn't cost a fortune to run.

I looked at prices for new EGR valves for it and they were around the £200 and I'm not prepared to spend that much money on it. I did find some 2nd hand ones on ebay for £40 ish, but theres no guarantee that they wont be knackered either.

My brother said they get full of soot and then the stick and thats what we think the one on the Maverick is doing.

[tigersaw]

you could try cleaning you old one with caustic soda?

[Luckypants]

I had exactly the same symptoms on X-Trail (2.2DCi) Fizz, EGR valve was disconnected and it has been fine for the past two years. Has passed MOTs no problem.

The symptoms returned much worse two months ago and the EGR valve was again checked for being the culprit - only this time it was a blocked fuel pressure balancer pipe on top of the tank.

Point is, if the hesitation and misfires are gone by disabling the EGR valve, it has most likely solved it.

Originally Posted by tigersaw

you could try cleaning you old one with caustic soda?

NOT recommended for parts that contain Aluminium though

[fizzwheel]

Recommendation was to take the EGR Valve off, and then clean with brake cleaner.

Trouble is to take it off, involves dismantling the intercooler and then trying to undo what look like some very rusty bolts that are holding into the manifold, which TBH I just dont fancy doing...

[andrewsmith]

Originally Posted by xXBADGERXx

NOT recommended for parts that contain Aluminium though

This.

Here's a how to clean the valves from YC's thread

Originally Posted by hardhat_harry

EGR valve going usually u see lots of smoke too when accelerating, you can clean them

http://www.youtube.com/watch?v=zMkx_utiGGc

[NTECUK]

Tdi will be fine.
It's only used on that model to reduce combustion temperature.
The egr only works when your cruiseing .No mot worries.