Help Hesitation/Misfire M3 E36 1994

I have hesitation/mis-firing at 2000rpm. Doesn't happen all the time, happens more if driven sensibly and can happen if the car is cold or hot. I have changed the 6 coil packs, plugs, o2 sensors, air flow meter, fuel pump, fuel filter, and have most recently taken the injectors out and had them cleaned and flow tested and all is well with them. Can anyone suggest anything as I have run out of ideas. If driven hard it doesn't appear to be so bad. Taken car to main dealer and they say there isn't anything wrong with it even though the technician test drove it with me and felt the hesitation himself!!!

hi mate,i was just wondering if you have sorted out your missfire problem,my m3 does the same thing

If it's a misfire first thing you should do a compression leak down test. I am just gonna guess on this one but seems like the good ole #4 has a problem. I have heard about a problem a couple times already where during compression testing bubbles will be seen in the coolant reservoir. The bad news is that either the head gasket is leaking internally or the head is cracked. Sometimes this is visible by inspecting the spark plugs and seeing which one has been getting coolant on it.

If it's just hesitation check the operation of the throttle position sensor. Good luck

Originally Posted by Fast1

I am just gonna guess on this one but seems like the good ole #4 has a problem.

He has a different motor than you do.

Holes in any of the rubber hoses that provide air to the engine (intake tract)?

Crank position sensor? Does this motor have it?

Regards,
Marc
95M3

I have been chasing this on my E36 3.0 Saloon for a while ( I am a BMW Technician).
Does the hesitation occur mainly between 1800 - 2200 RPM, mainly under light to moderate throttle and worse during warm up ?
Also, does your engine pink under moderate load in warm weather (ie above 22 deg C) ?

Originally Posted by Wizwam

I have been chasing this on my E36 3.0 Saloon for a while ( I am a BMW Technician).
Does the hesitation occur mainly between 1800 - 2200 RPM, mainly under light to moderate throttle and worse during warm up ?
Also, does your engine pink under moderate load in warm weather (ie above 22 deg C) ?

Hi,
I have the same problem you described on my BMW M3 3.0, could you tell me how did you solve this problem, please?

Thank you for your help!

i have the same problem,any clues yet

Hi,
I have a similar issue. The car had a few niggles when I bought it including a bad petrol (gas) smell, very lumpy idle, rough running when cold on a constant throttle.
Took it to a good 'M' specialist to give it a good looking over who cured the petrol smell (leaky fuel pipe in engine bay) and the lumpy idle (bung/rubber cover missing off throttle body) and all seemed well.
After driving it in town in heavy traffic in hot weather the car started being hesitant on constant throttle on the motorway and even a bit when accelerating.
When it had been to the specialist the only code that came up was because of the bung missing. Vanos was fine. New fuel filter fitted. Car drives fine otherwise. Happily pulls to 7k on a daily basis

Has anyone got any ideas before I go through the plugs/leads/coil packs route?

Many thanks in advance.

Oh, it's an E36 M3 3.0L '94.

Had the same problem, replaced 6 coils (with BavAuto HP) replaced O2 sensors, replaced fuel filter. Car ran fine wide open but stumbled in mid-range. I can't believe it myself, but I replaced the plugs and it is fixed. When I replaced the coils (I thought I was making an upgrade) I put in new plugs, but I chose the two prong Bosch instead of the four. The recent replacement was back to a set of four prongs, which is what were in the car to begin with. I still can't believe it, but it's fixed. (I've seen since on other posts that the NGK iridium IX plugs are highly recomended.)

Thanks for the reply. I'll look into the history and see when the plugs were last done and what they used and maybe get a set of new ones ordered up.

Don't put the Bosch 4 prongs in, they are known to be fragile and lose tips.

Originally Posted by Bruce

Don't put the Bosch 4 prongs in, they are known to be fragile and lose tips.

I've had Bosh Platinum Plus 4's in my M3 since 2006. They seem to work fine for me. Just a note!!!

That doesn't sound very good.

Got the same issue! New coils ordered today along with NGK two prong copper plugs...wish me luck!

Sent from my PC36100 using Bimmer App

So, it's my first post here (HI EVERYONE! ) and I've been looking for a solution to this problem for a few months now. Changed coil pack, spark plugs, fuel pump, fuel filter, crankshaft position sensor, camshaft position sensor, fuel pressure regulator and cleaned up fuel injectors to no avail. Did anyone find other solution besides changing the spark plugs??? Pleeeease

Helloooo!

bump

You might try making a new post in the plain E36 forum (this is the E36 M3 forum).

Same issue with my 94 m3 3.0L euro.
Replaced tps, fuel filter, manifold rubber o rings, cleaned icv, checked for leaks andfound none, and i am wondering what to do next.
Oh, and plugs were replaced two and a half years ago with bosch cdd5y.

any one here as the magic solution?