Exhaust Solenoid

[rmoconnor41]

The car has struggled with an erratic idle when cold.

On the suggestion of @AntStark I disconnected both Vanos solenoids and the car started and ticked over perfectly. @AntStark and I changed the inlet solenoid last year so I started the car from cold again with only the exhaust solenoid unplugged. Car ran smoothly until I plugged the solenoid back in. The Vanos seals etc were all changed within the last 3000miles by @Lee so I know that was done properly.

Why would unplugging the solenoid correct the cold start erratic idle?

With the limited access to the exhaust solenoid, what is the best way to get this 27 year old solenoid out?

 

[Lee]

Have you changed that exhaust solenoid yet? Both those solenoids have an inline check valve too so that might need cleaning, located in the block I believe. Also oil quality and correct filter can affect the Vanos unit.

Scrap that no check valves on the M52.

 

[rmoconnor41]

Not changed yet because of the access to that Solenoid is a bit more tricky.
Other items are as specified by BMW

 

[Lee]

Not changed yet because of the access to that Solenoid is a bit more tricky.
Other items are as specified by BMW

Can’t think of what might be in the way, maybe the fan. Should be able to squeeze in a 32mm spanner.

 

[rmoconnor41]

 

[rmoconnor41]

The first photo is the solenoid with the connection removed the second is looking down from the top. Shroud and fan prevent access for a spanner

 

[Lee]

That’s the kiddy. Some crazy angle with the spanner or a crows foot 32mm will do it.

 

[rmoconnor41]

@AntStark and I weren’t sure why this solenoid would affect the Vanos at cold start which results in a terrible idle until warm.

 

[rmoconnor41]

That’s the kiddy. Some crazy angle with the spanner or a crows foot 32mm will do it.

27 year old solenoid will take some welly to undo I imagine

 

[Lee]

27 year old solenoid will take some welly to undo I imagine

Should be fine, if you fart trying to undo it might be worth waiting for @AntStark

 

[rmoconnor41]

Should be fine, if you fart trying to undo it might be worth waiting for @AntStark

@AntStark is my go to Z3 support. We thought a box spanner might be easiest.
Just waiting until my car is back next week from getting its new roof fitted. Found the roof tensioners in US for $40 rather than €170. They don’t post overseas. Luckily found a way round that.
Also planning the new throttle cable and some seat bushes too.

 

[AntStark]

@AntStark is my go to Z3 support.

It’s amazing how much pure enthusiasm compensates for complete lack of mechanical talent