Strange problem with my car

[StickShift]

Hi guys


I have strange problem with my e34 1992 520i

The problem is when i sit heavy traffic on hot days. The car will idle and all of sudden the engine will become very rough idle like it running out of fuel and then will die and when you try a start it. The engine will not turn over then i have to wait about 20mins then it will start.


any idears what is the cause of the problem

 

[Major]

Sounds like either your coolant or air intake temp sensors are dying under hot conditions and leaning out the car. Might want to run it past the dealer to get a code, or find someone here who has a diagnostics tool to see which one it is.

 

[freerider]

I would also be inclined to say it sounds like one of the sensors thats going a little wonky

 

[StickShift]

Could it also have any thing to do with the fuel pump as will ?

 

[freerider]

I wouldnt bet on that.

 

[Major]

Does it go away once you're driving again? Next time you come to a stop, do the problems immediately continue?

 

[StickShift]

It only seems happens in stop and go traffic

If i am on slope i can jump start it and go again for a while and it will do it again

 

[zaleonardz]

Does the motor crank after it has stalled, ie starter kicking in ?

 

[andrewbuch]

could it be that dam flux capacitor?

 

[zaleonardz]

knowing stickshift, its highly possible

 

[StickShift]

Does the motor crank after it has stalled, ie starter kicking in ?

it does nothing

 

[zaleonardz]

Then a quick diagnostics could be altenator.

The starter circuit is void of a great deal of electronics on the 92 model, and it sounds as though on low revs, it is not pumping through enough current to charge, so you run out of power.

Reason why you have to wait 20 minutes, you have an aftermarket amp installed that has caps that stores power, when you power down, those caps release power back into the system, meaning that charges up the battery.

I may be being a bit stupid here, but that sounds like it could be the issue.

Fact that your starter is dead to me is the clue.

 

[Raybimmer]

I have similar prob with e36 325i . replaced regulator/brush holder ( bosch ) in alternator , no improvement . replace solenoid and brushes in starter , no luck . now park on down hills and run start ok . If battery is nearly flat ( rode car with starter out so alt lead was not connected to starter pos lead to charge battery !! ) then windows slow and car revs slow and misfires, but does not cut out .Get home,charge battery replace starter and bit better - maybe low voltage. When your car goes rough check if electrics work, does radio/cd play ok,windows wind ok, if not then may be voltage low .
Gremlins rule !!!!
Hope you get sorted, bmw heavy to push !!

---

Ok, time to think : will checking voltage at battery terminals with car running give say 13.5 volts and after say 15 or 20 mins show say 12.0 volts indicating battery losing charge/alternator charging too little ?:wave:

 

[zaleonardz]

Ray...

12V is enough to power the system, if you are getting 12V the car will run, so using your theory, 13.x volt and the battery is charging.

If the rate of charge drops too much, meanign that you are pulling more power then the altenator can supply, you will get a simple run down from 12 to say 10 or something, and it will then cut out.

Lets say you are getting 13v or 12.x volt, the rate of battery voltage under load will just simply decrease.

I would take your altenator to a specialist, it could be that it has shorted open circuit (which will not give you an alt light), and making the changes that you have indicated will not help.

The armeture could also have collapsed, meaning that the coils are not aligned with the windings, meaning no charge anyway.

I have a contact in the South, had the E34 altenator rebuilt for 400 bucks, I just really wished I had done the regulator at the same time, it charges, but only after say 2000 rpm, so when im sitting in traffic, if I dont keep the revs up, I actually run the battery flat, and stripping out a alt out of an M60 is like giving birth to a hedgehog

 

[Raybimmer]

Stripping a starter out of an e36 325i ...gives birth to new vocabulary !!
If battery gives reading of say 12.5 volts with car switched off and then say 13.5 with engine running then alt should be charging ??
Can alternator be charging less than battery is supplying,leading to flat battery?
( Pity battery is alone in boot , maybe belt drive off rear sideshaft to alt mounted under boot may be answer - short cables to battery :clap::excited
Any news StickShift ?

 

[StickShift]

Stripping a starter out of an e36 325i ...gives birth to new vocabulary !!
If battery gives reading of say 12.5 volts with car switched off and then say 13.5 with engine running then alt should be charging ??
Can alternator be charging less than battery is supplying,leading to flat battery?
( Pity battery is alone in boot , maybe belt drive off rear sideshaft to alt mounted under boot may be answer - short cables to battery :clap::excited
Any news StickShift ?

I am going to take the starter motor out and check the brushes and bearings and also check if the solenoid is getting stuck

 

[zaleonardz]

But a faulty starter would not cause the car to cut out.

Ray, my altenator does not charge at idle, or supplies too little, I can literaly run by battery flat while sitting in traffic.

Good luck Stickshift, let us know

 

[StickShift]

But a faulty starter would not cause the car to cut out.

Ray, my altenator does not charge at idle, or supplies too little, I can literaly run by battery flat while sitting in traffic.

Good luck Stickshift, let us know

I think i got two different problems. One with the starter and two the car cutting out

so i will look at the starter then try and diagnose the cutting out problem