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Discussion Starter #1
Now that I've changed routes I'm finding that the car seems to judder a lot in slow moving traffic.

The day is a bit carp, 6 miles including 5 roundabouts and 3 sets of lights in 6 miles.

However the car seems to really judder going through the tunnel. Jerking forward so much I have to ride the clutch at times.

eg. Doing 20 mph but the revs drop to 700 and I can feel the car juddering. I don't want to try and slip the car into 1st whilst I am moving as that can be just as bad.

What do peope think?

Coilpacks?
 

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At that speed in 2nd you may just not be giving it enough throttle to keep the revs up and it may be bogging down a bit.

I get a similar thing in stop-start motorway/London traffic where 1st is too high and 2nd is too low, and it's a right pain, but I either try to put slightly more throttle in, or as you've found, feather the clutch.
 

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If you get an opportunity Ebbers , try another MAF .

Also , check the basics i.e. plugs , air leaks etc .

That said , as Tony rightly pointed out , 700rpm is extremely low revs for an S38 engine and a simple shift into 1st gear may be the solution at 20mph ......these cars aren't afraid of being driven briskly !

D
 

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Discussion Starter #4 (Edited)
Cheers for the replies lads.

I think that's part of my problem, I've heard so many horror stories about things going wrong that I'm afraid to drive them like a proper car in case something drops off!

Althugh saying that I just don't think I have the minerals to drop a car from 2nd to 1st whilst doing 20mph. A lot of cars just don't like it.

The reason I said coilpacks was because the car has done almost 90,000 miles and I think they are all original. The MAF probably is too as I can't see a receipt for it :(
 

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Cheers for the replies lads.

I think that's part of my problem, I've heard so many horror stories about things going wrong that I'm afraid to drive them like a proper car in case something drops off!

Althugh saying that I just don't think I have the minerals to drop a car from 2nd to 1st whilst doing 20mph. A lot of cars just don't like it.

The reason I said coilpacks was because th car has done almost 90,000 miles and I thin they are all original. The MAF probably is too as I can't see a receipt for it :(
Just do a good, solid blip of the throttle with the clutch engaged and it'll slip into 1st quite easily (1st is good for an indicated 32mph).
 

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With both of the E34 M5s I've owned, lumpy running at low revs is a characteristic of this engine.

I spent a lot of money on the first example I owned having coilpacks replaced, throttle bodies balanced, and so on - only to find it improved things only slightly - I just wasn't used to the low-rev 'lumpiness' of the S38B38.

I wouldn't drive it too far at 700rpm - with warm oil you've got fairly low oil pressure at such low engine speed......as DavidOli says - this motor thrives on revs....:hihihi:
 
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