Throttle cut out and stalling

[sandrune]

So the m42 has been cutting out for a second while driving and then pick back up where it was. Jerks me as it happens. The check engine light and the anti lock light both come on for the second when this happens and then go away. Stomp test it and no codes are there. Was able to drive or a week or so with it happening but today it kept happening right after each other and just now it stalled out. Can sit and idle no problem. But try to drive again and it'll stall

What's going on.

Sent from my Pixel XL using Tapatalk

[sandrune]

Also doesn't seem to do it while I rev it out of gear

Sent from my Pixel XL using Tapatalk

[TobyB]

Main relay.

Engine ground.

Main harness has a break/ loose connection.

guessing over the internet,
t

[sandrune]

Main relay.

Engine ground.

Main harness has a break/ loose connection.

guessing over the internet,
t

Engine ground off the alternator could be a culprit? Mines got maybe a 1/4 still connected...So when I'm driving it jostles around and kills the power?

Sent from my Pixel XL using Tapatalk

[roguetoaster]

He's talking about the ground at the passenger engine mount to chassis, but alternator to engine mount arm/block is also one that needs to work to keep the charging system working. Basically, odd lights on the dash are often a sign of a weak charging system or a bad ground.

You can of course check battery voltage when running and determine if the charging system is weak. But you might as well replace suspect grounds for future peace of mind, although they are available new from BMW BavRest is also a good source for a kit of similar quality.

[sandrune]

He's talking about the ground at the passenger engine mount to chassis, but alternator to engine mount arm/block is also one that needs to work to keep the charging system working. Basically, odd lights on the dash are often a sign of a weak charging system or a bad ground.

You can of course check battery voltage when running and determine if the charging system is weak. But you might as well replace suspect grounds for future peace of mind, although they are available new from BMW BavRest is also a good source for a kit of similar quality.

Hmmm no that one still looks good. Just has some oil on it from a small leak somewhere

Sent from my Pixel XL using Tapatalk

[5Toes]

mine looked that way, maybe a bit worse, and caused a massive headache. replace it anyways its cheap!

crank sensor... ya I know everyone points the finger at it really quick but if your tach is not losing its signal then its likely good.

My other guess is a wonky air flow meter

[sandrune]

mine looked that way, maybe a bit worse, and caused a massive headache. replace it anyways its cheap!

crank sensor... ya I know everyone points the finger at it really quick but if your tach is not losing its signal then its likely good.

My other guess is a wonky air flow meter

Alright I'll go in a swap it. My speedometer has been fine but my tach has been a little weird lately. Some days it's says I'm at no rpms. I've got a spare engine I'm building on the side, so I can easily swap things and find out.

Sent from my Pixel XL using Tapatalk

[5Toes]

your cluster probably needs re-soldered. my m42 sedan's dash needs a smack some mornings nowadays for the tach to work.

bavrest makes great cables they just take a while to receive.

My car too starves for fuel when cornering hard. It is because I have a walbro 255 that does not pick up fuel as low as the stock pump... some food for thought. A hard fuel cut is very easy to identify though