[coopersim]

I've got a small but noticeable surge when on cruise, the speed remains the same but driving a long a level bit of road I can feel a strange surging sensation and the mpg gauge twitches at the same time

It's not changes on wind resistance, so I can only think its a fault of sorts but there's no stored codes

I've had this for a while and was hoping its related to the glow plug issue, but since I've sorted that and it's not cleared I could do with some ideas, vanos unit was alli could find elsewhere, is that plausible?

[ade146]

Only a suggestion as it could be a few things but I had mine do this at very specific motorway speed. Happened a few times when my egr was sticking. at about 75mph I think it is asking for lots of egr and as the load changes the egr varies. It would sometimes hiccup like it swallowed a small rodent. I pretty much guessed what mine was by the feel and by no means certain about yours but its worth a look.

[coopersim]

Thanks for this, I'll give the EGR a clean

[ade146]

Easy enough you just need a slightly bendy tool to get at the bottom allen bolt. They are very stiff to push open. I havent had it happen since I disconnected my egr.

[coopersim]

Thanks

Any special precaution?

Am i ok to use regular carb cleaner?

[coopersim]

Ok, I've cleaned it out, it wasn't as bad as I was hoping (thinking it would be the fix)





Just need to test it now, and report back

[Dr Dave]

I too would say it was an EGR issue. Fingers crossed for you.

Might be an option to blank the EGR off.

[ade146]

Agree with dave try it disconnected if the issue comes back. It doesnt look too bad to be fair but it doesnt have to stick much for you to notice on low loads. I wasnt really sure from your description but it doesnt hurt to clean the egr. I notice at slowish speeds (sub 70) they do seem to pursue the set speed fairly aggressively so you can feel it slightly on and off the throttle but it is slight. It is on a very steep part of the torque curve at that point.