power loss - BMW Forum

kevin71 · 08-23-2012, 07:19 PM

Hi all,

I have a E39 535i, 1997 model. I recently replaced the engine (M62). All was going well for about a week after engine replacement, then 2 days ago I was driving and the car started losing power. By losing power I mean losing spark, I'd be driving and the tachometer would drop to zero and I'd have no acceleration, all other electrics would stay on, this would last for about two seconds and then I'd get power back. I have noticed this only happens when the engine is warm, driving for at least 5 kilometers. also when the engine is warm it does stall when I come to a stop and it restarts sometimes first go and sometimes it takes two or three restarts. If I leave it off until the engine cools down it runs without incident for about five kilometers. I have cleaned the ICV, the ICV is my original one and it never gave me trouble before, same for the MAF sensor. Any Ideas what could be causing this issue?

Lord Vader · 08-24-2012, 02:50 PM

Have the DME and the OBD system scanned for trouble codes. That should give you a good starting point. If the car is randomly not sending a spark to the plug it may be a DME issue.

kevin71 · 08-24-2012, 06:53 PM

it's not giving any codes

Eliase · 08-25-2012, 01:27 AM

When it comes to BMW cars these are highly equipped with latest technologies and accessories. And I like these for driving. You would be amazed that I have 5 cars.

kevin71 · 08-25-2012, 08:07 AM

Quote:

Originally Posted by Eliase

When it comes to BMW cars these are highly equipped with latest technologies and accessories. And I like these for driving. You would be amazed that I have 5 cars.

and what has you having five cars got to do with the problem I am having with mine?

westin · 08-25-2012, 11:54 AM

did you check compression these bllocks did have a few problems

kevin71 · 08-25-2012, 06:35 PM

Quote:

Originally Posted by westin

did you check compression these bllocks did have a few problems

compression is fine, thinking it's an electrical issue that's not being picked up for some reason

Lord Vader · 08-25-2012, 10:30 PM

I will agree i think this is electrical. Best bet is to go through your engine bay and check all the wiring. Check and make sure all connectors are properly secured and tight. Check all other wiring looking for fraying or possible shorts. Its simple, but it may work. Lets start ruling things out one at a time.

What spark plugs did they put in?
Have you checked your coil packs?
Is their any cylinder in particular thats having issues?
Is your injectors and fuel rail properly installed and not loose?

Theirs a mess of wiring underneath the cabin air filter location atthe base of the windshield. Check that as well.