'98 M3/4 ... Is this normal?

[Marcus]

I recently bought a '98 M3/4 stick. Love the car, but ...

When I start the car in the morning, it idles real rough. It wants to stall. If I give it a bit of gas, it hesitates slightly, until warm up. In fact, one cool morning, when I moved from reverse to 1st gear, it stalled.

Does this have something to do with the O2 sensor, or is this simply a sign that the car needs a tune up? Or is this normal?

In addition, my factory installed keyless remote and alarm system does not retract my driver door lock anymore when engaged. Like I said, I'm happy with the car, but these little things are bugging me! Do you know if the door lock mechanism is under warranty?

Has anyone out there experienced similar problems?

Marcus.

[nodemgr]

Haven't had either problem, sorry. I hope they are easy fixes.

[Bob ///M3]

The rough idle and hesitant throttle response is very common for the first two minutes after the engine is cranked up. BMW has a software fix for this which is free if the car is still under warranty however it only helps the symptom but doesn't totally fix it.

The reason why it idles roughly when first cranked up is because the engine runs rich plus an air pump is running for the first two minutes to help reduce emissions which plays games with the O2 sensors, etc. There is more to it than that but I think you understand...it's common.

If the engine runs smoothly after two minutes or so, you can be assured you have no problems.

You may have a solenoid switch that needs to be replaced for the locking mechanism on the driver's side door. Other than that, I have no clue what the door problem may be if it works the other door lock okay.

The little things do mean a lot and can be aggravating to deal with when they don't work but BMWs have a good history of having fewer failures than most.

The door should be easy to get repaired.

Enjoy!

Bob ///M3

[NormK]

I have a '98 M3 coupe (only for 2 mo). I have not experienced the rough idle at all, even when it was severely cold in N. England. Does the problem happen from day-1 or could it just come on suddenly later?

[Bob ///M3]

Most of the time it's not really a rough idle as much as a lack of normal throttle response, described by some as a hesitation or tendency to bog slightly when throttle is applied.

The easier you apply the throttle during the first two minutes after crank-up the less likely you are of even knowing it has this symptom.

For most owners, they may realize the lack of a quick, normal throttle response when they first own the car but then they just get used to it and it becomes normal.

It's nothing that can't be lived with very easily. It's just the way it must behave due to design.

Bob ///M3

[Marcus]

Yeah ... The car runs smoothly after the first 2 minutes, so I guess it's not a major issue. I'm still going to take it in to the dealer to get the ECU upgraded for the cold start idle problem, since it is still under warranty. I live up in Canada, so some of the Spring and Fall mornings are kind of cool.

Thanks for the wise words. Very much appreciated!

Marcus.

[NormK]

Throttle response - OK - I misunderstood and was focusing more on "idle". Maybe I haven't noticed it because I usually let my car warm up about 30-60 sec before driving off and when I do I usually baby it for the first 2 mi or so. I'll check it again, driving off sooner and applying throttle a little harder and see if I notice a difference. If I have the problem, it's obviously been easy to live with if I didn't really notice it.

[gschomi]

Norm, I have the same "cold start" problem also but it goes away after a few minutes. I had the software upgrade done by the dealer but i really did not notice any change. Just let it idle for a few and you will be OK. Cant help you out with the door lock problem though. Are you still under warrenty?

By the way you have a nice car., same as me.

happy motoring

[Texas M3/4]

My 97 does the same thing. As Bob said it is common. Mine actually goes away after 30 seconds. I though I remember reading somewhere that this is when the DME goes from a open loop to a closed loop? Something like that. But I start the car...its idles rough sometimes less sometimes more but 30 sec or so later it is always good to go (or at least as much as I push it till it warms up) and the idle settles in right at 600ish or so.

No worries.

[Yackedy Sacks]

I used to have this problem too... until I installed the shark injector. The startup is no longer rough... but there is still a lag in throttle response the first few minutes.

[NormK]

To gschomi: FYI - Thanks but I don't have the door lock problem (or maybe not even the idle problem). I was just inquiring about the idle problem to get more info. I think you probably meant to reply to Marcus - the original poster.

[gschomi]

Originally posted by NormK
To gschomi: FYI - Thanks but I don't have the door lock problem (or maybe not even the idle problem). I was just inquiring about the idle problem to get more info. I think you probably meant to reply to Marcus - the original poster.

LOL. Sorry., i was trippen out. Yes i meant Marcus.

Happy motoring:p