E30 Zone

Hoping someone can offer me some advice on what may be causing juddering / vibration which is most noticable between 2 and 3000 revs. It almost feels like power is being delivered unsmoothly.

Above 3000 revs it isnt really noticeable. Its most obvious in 3rd-5th, and sometimes in 2nd it feels like it 'kangaroos', but i dont know if this would be a different problem?

Any suggestions welcome. Cheers.

Hard to say on this one fella. Normally things like this are down to distriutor cap and rotor. But would be looking for air leaks too.

try the basics first... leads dizzy and rotor.. and plugs.. i would replace the lot if you havent done so already..

OK Great, thanks for the quick responses.

I forgot to say that it doesn't seem to happen when accelerating, more just when cruising at constant speed. Don't know if this affects what you think it may be?

check the dizzy and rotor for signs of deteriation... then go from there.

Whats the milage on the car ?
For a few more answers do a search for "kangeroo" on the technical page.

Its just turned 100k Miles.

Will have a look at that page, thanks

Nick, did you end up sorting this problem? The reason I ask is that my e30 sport has just started doing the exact same thing. Car accelerates fine but when cruising between 2k-2.5k revs the engine seems to judder causing the car to kangaroo. So far i've replaced the rocker gasket and have checked all vacuum hoses, all seems fine, also put news sparks too and still no change.

Cheers


Wayne

Hi Wayne,

No i still havent actually got around to doing anything with it yet! Been too busy with work etc! Will try and have a look at it this week though. Let me know if you manage to sort yours though.

Best of luck

Nick

nickbentley wrote:Hi Wayne,

No i still havent actually got around to doing anything with it yet! Been too busy with work etc! Will try and have a look at it this week though. Let me know if you manage to sort yours though.

Best of luck

Nick

I'm hot on the case at the mo, to date have done the following:-

- Checked all vacuum air hoses around AFM, TBH & inlet Mani (All are good)

- Replaced rocker gasket as there was a slight oil leak (This helped but only very slightly.

- Removed oil filler cap while engine running which caused it to judder a bit therefore indicating there are no air leaks (I Think )

- Tested coil primary and secondary resistances which were fine.

- Renewed all sparks. At the same time inspected all ign leads which were good.

- Removed and inspected dizzy cap & rotor, no cracks, cleaned and removed oxidation on contact points. This appeared to help but again only very slightly.

Bit stumped as to what else I can check, perhaps swap out ECU for a known working one, and maybe check continuity of wires between ECU and engine sensors (ie thottle position sensor etc).

The investigation continues

I have this exact scenario - any more ideas?

Ihad the same problem about a year ago changed fuel filter and juddering stopped

I was thinking to have a go at the fuel filter. Will try that first - has not been done in a year (12k miles) - what's the service interval supposed to be? Sorry don't have haynes handy

edit... I do tend to run it quite low which could reduce the lifespan ...

Reckon its a worn part of the track on the AFM - tell me I'm wrong

DME Relay and fuel pump relay?? The DME relay provides power to the ECU. My BMW mechanic who was at a main dealer when e30s came out told me that they had many problems like this caused by dodgy relays and he had to change out lots and lots. On my 318i and 318is these relays sit behind a long thin plastic cover in the engine bay just below the windscreen wipers. About 20 quid in total from main dealers. Or swap out and test with ones known to be OK from another car?

Ht leads my car used to that well when i was cruisin they were completely gone after I changed them it was fine