Engine stuttering at low RPM - HELP!!!!!

[shane@mbtech]

Headgasket

Hope not, but sounds like a possibility to me

Ask them to do a compression and leak down test

[s.mac]

mines at Murketts this week with the same problem, I will let you know what they say

[shimmy]

my HG failure was mainly noticable at high revs and not at idol.

slowly got worse lower down the rev range as i drive it more. I noticed it quite early i think as the trackday with Bealo was proof that it was playing up (he started keeping up)

By the time id driven home and then half way to simpsons it was considerably more noticable

I reckon it may be somethings else rather than HG (have either of you had any noticable increase in water/oil temps esp during the summer at trackdays?

[s.mac]

nope, mines definitely over fuelling, i think its a sensor some where

[shimmy]

nope, mines definitely over fuelling, i think its a sensor some where

when mine sounded really rough at low revs it was sensor in headers that had gone manky, but a fault did regsiter

[outnumbered]

Hi,

I'm getting a little concerned that BMW are still unable to find the fault with my CSL.

At low RPM in high gears if you place the throttle fully down the engine starts stuttering until the revs gets higher, forcing the car backwards and forwards (kangaroo effect!)

On power the car is absolutely fine. Its slowly got worse and worse throughout the last few months.

BMW have the car at the moment as its under warranty and they have replaced all the coils and spark plugs, a few different sensors etc, and even the clutch.

They are now balancing the throttle bodies and realigning the shims etc, which ive got to pay for??

Has anyone ever experienced this problem. They have had the car in and out for nearly 3 months.

Its gradually got worst and even sometime cuts out completely, almost like some is switching the ignition off very quickly.

So frustrating.

Any help or advice would be most helpful, as i think they really are clutching at straws!!

Thanks

Sure your car doesn't have a dodgy map on it ?

[NZ_M3]

At low RPM in high gears if you place the throttle fully down the engine starts stuttering until the revs gets higher, forcing the car backwards and forwards (kangaroo effect!)

What RPM and which gear? Is the car warm or cold?

Dealer diagnostic tools are capable of data logging on road tests, so technically speaking if they know what they are doing they should have been able to trouble shoot it.

Have they checked fuel pump?

[cantfind1]

Sounds like you have a lazy throttle actuator. They are prone to failure they can get slow when depressing the throttle. Will not throw a code as they are technically still working.

So to summarise when you are just cruising along at low revs in a high gear you push the throttle to the floor now the ecu pushes more fuel in but your throttles are slow to react and the car will run rich and bog down or kangaroo.

Could be your problem.

[s.mac]

thats mine to a T , I will mention it :thumbs:

[TANKSLAPPER]

I reckon it may be somethings else rather than HG (have either of you had any noticable increase in water/oil temps esp during the summer at trackdays?

I had that matey, only once.

what causes this Dr Shimmy. lol

T$

[toofastforyou]

blow the engine then get a new one under warranty, bmw cant argue with a blown engine

[DazBlackCSL]

blow the engine then get a new one under warranty, bmw cant argue with a blown engine

constructive :smt100

[shimmy]

:thumbs:

constructive :smt100

he has a point though:thumbs:

[Niall]

If no faults codes are stored in the DME, dealers are limited to what they can do under warranty (especially with insured / extended policies) however that doesn't mean they can't fix it. As mentioned earlier I would request a compression and cylinder leakage test are completed and ask for a copy of the results as I've seen the symptoms you describe caused by a head gasket failure.

In that particular case the car needed a block & pistons as the a groove had been cut into the block between the two of the cylinders as a result of the cylinders blowing into each other where the gasket had failed.

Hope you get it sorted.

[toofastforyou]

constructive :smt100

if the car is under warranty, and there is something wrong with the engine, and bmw is refusing to fix it, i say give em a reason to fix it that they cant say no to. can you think of a better reason than a blown engine?