Well, there was a hesitation, it has now become an all out stutter.  The car just has no power (almost like it wants to backfire and clear the problem). Up above 3k it flies, but the problem is getting worse.

usual stuff from main agents, no help whatsoever, even to the point of taking them on a test drive and they still think its ok.

I've heard about problems with the vanos, but these seem to be on the evo.  Anyone out there who can help, advise,etc would be great as its really starting to get on my ****.  HELP!!

Brett - thanks.

I have always run the car on at least super, and more recently optimax.  The car was doing it mainly when cold, and normally only in second or third, but for the past month or so its been hot or cold, and any gear.  i have found that if I accelerate hard through the rev band its not as bad, but if I come through it slowly, its like a diesel!

Its just ahd a major service, so its not the plugs.

I've had the car about 18 months, and it has done it on and off since then, but its really bad at the moment.  For the first time since I've had it, the problem occurred in fifth the other day.

I was thinking baout getting the chip remapped to see if that would smooth it out, but I'm worried that without knowing what the problem actually is, it might make it worse.

Tristan

Tried that a couple of times already, but no improvement.  Thanks anyway.  with my luck, it isn't going to be a cheap solution!!  Assuming it can be solved that is.

Brett

Might try that, but I've also heard that the throttle position sensor can cause prolems with flat spots, but who knows!  Its funny that in all the stuff I read about them before I bought it, none of them mentioned anything about this problem.  Dam!

Edited to remove objectionable language, please read the forum guidelines

Yep Mine Does it....

On mine I have had New O2 sensors, New Coils, Plugs, Valves adjusted, 3 lots of injector cleaner.....I had a new ECU as it had no output to 1 of the O2 sensors but I aint gonna go there as thats another story!

I use mine everyday....it is a nightmare car as an everyday motor....it is getting more liveable now the weather is warming up cos the engine runs a bit better as it warms up quicker. But when it was 0C-4C it would sit on tickover and splutter dropping cylinders....LOL it would even make the car shake it's booty. Bit embarrassing on the type of car it is. The only way to drive the M3 is to drive it flat out all the time.....problem is I cant do that as the traffic round my way wont allow it....I end up listening to me tunes whilst stuck in traffic.

I had my motor put on the dyno this week and the dip showed up on the dyno....happens when you hit 2200-2500rpm then it clears itself and is fine up to the readline. This is on the Evo that came with me but his was slightly worse. Unfortunately I dont have a scanner so I cant put mine up but you get the idea.Top curve is torque and the bottom line is power

You can also check out the thread cos I mention it in there.

http://www.bmwcarclubgb.co.uk/forum/forum_posts.asp?TID=6673&PN=1 - http://www.bmwcarclubgb.co.uk/forum/forum_posts.asp?TID=6673&PN=1

I forgot to mention.......I have heard that the reason why we get the dip on the power at 2200-2500rpm is for the emissions.....they lean it right off so it is on the limit and as the car gets older it gets worse that why we get the annoying flat spot!  dunno if it is true??? As a lot of mechanics talk ****e!

A chip might cure it.....well its gotta help....IMO it needs more fuel especially when its running cold as it feels to me like its not getting enough fuel that why it feels wooley until it has warmed up a bit.

The best bit for me is I have a massive hill right where I work....I end up with Golf GTI company motors right in me boot cos I have to struggle up the hill like a 1.0L Nova! LOL

I need a sign in the back window "BACK OFF MOFO MY CAR HAS TO WARM UP! THEN I WILL KICK YOUR ASS MOFO!"

kevin wrote: Mono You need that on a electric rear blind so that once you are warmed up you can roll it down.

Yeah I thought about that......sorry to be sarcastic.....but if it was electric then it would probably keep packing up all the time as BMW electrics dont seem to be the best.....LOL  

hehehe the thing that is gettin on my **** is doing the window up.....it keeps going back down!! it is a common fault.....okay add that to the list of things to go wrong!!

Its a love/ hate relationship with my car!

andym3 wrote: jus had a look at the graph again from the rollers the other day again there an there is the exact same dip in torque as the graph above, mine not an evo but jus the 3.0, wot the **** like, would put the graph up but don't no how,

Andy,

Dude, my graph is similar to the evo but it has less of a dip at the 2200rpm mark and has more power from 4000rpm upwards?? but mine has the decat and ACS rear box.

It is a pain as it makes the car annoying to drive sometimes....I wonder what the cheapest, best fix is to sort it out??

mine drops the same as the evo if not more, but mine seems 2 b making more torque than it, but surely the evo should have more, it sits an idles not a problem don't matter how cold it is in the morning's not a problem there, its jus that annoying flat spot wen u drive easy, but wen u drive it hard u never notice it, mine has a magnex backbox an a k&n airfilter. wish i new wot u could do bout it, its jus a joke the way they all do it but no1, including bm don't no how 2 fix it,

Might be right about the running lean thing.  I had the airflow sensor disconnected (simply unscrew the plug on the box on the rhs of the engine).  It richens everything up and now the problem is virtually gone.  I actually have power below 2500 rpm!!!!!

Anyone else with the problem want to try it and let me know what its like.  Don't know what its going to do to the fuel consumption though, but who cares!

biffa wrote: Might be right about the running lean thing.  I had the airflow sensor disconnected (simply unscrew the plug on the box on the rhs of the engine).  It richens everything up and now the problem is virtually gone.  I actually have power below 2500 rpm!!!!! Anyone else with the problem want to try it and let me know what its like.  Don't know what its going to do to the fuel consumption though, but who cares!

Hey Biffa,

That isnt a good idea mate....the airsensor is there for a reason. Also it will show as a fault on the DME now....

Interesting you say it improves it?? I guess the ECU would go to limp mode and use base settings....

I was wondering about documenting this thread and sending it to the tech team at BMW and see what they make of it???

biffa wrote: Might be right about the running lean thing.  I had the airflow sensor disconnected (simply unscrew the plug on the box on the rhs of the engine).  It richens everything up and now the problem is virtually gone.  I actually have power below 2500 rpm!!!!! Anyone else with the problem want to try it and let me know what its like.  Don't know what its going to do to the fuel consumption though, but who cares!

think your rite m8 i tried that out, did seem to smooth out the flat spot between 2 & 3000 rpm, sayin that, to me it felt a bit slower higher up the rev range (maybe just running to rich now), ive it connected back up again and the flat spot seems 2 b back, I wonder if u chipped it could u not get it to run richer at the low end of the revs? cos that seems to b the problem,

I wonder if it is worth speaking to a chipping company to see if they have done any chips to the 3.0L.....be interesting to find out....thing is who to trust??

As everyone seems to in it for the green stuff these days!!

"Of course sir we will remove all the flat spots give you 20hp more" err that will be £600!

theres a fella near me here does the rolling r,d who's pretty good does ne tuning work i can't do meself, he does chips, not sure wot make, but if i get a chance 2morrow i'll try an get a word with him, c if he's done it b4 or if he thinks it would help.

Been running it a couple of day without the sensor connected and it was fine, reconnected it and its running flat again.

Agree with the top end power loss though, and I'm sure it is running too rich up there.  Its quite an interesting dilemma.  you'd think that with a decent air filter, the throttles balanced properly (I drove a 3L that this had just been done on and it was a flying machine) and a chip to remap this apparent fuelling problem, it would be sorted. 

Biffa,

Sounds like a good idea.....Let us know how you get on, then I can get mine done LOL