KwS's not M3, M3 Project (or, the M328i)

[M3AN 4016]

Wow, way more complicated DME than on the single-unit MSS50 (S50B32).

Only observation/adjustment I'd make is that I'd remove the feeder tube from the expansion tank rather than bending/stressing it - I've had one crumble in my hands before.

 

[KwS 2425]

12 minutes ago, M3AN said:

Wow, way more complicated DME than on the single-unit MSS50 (S50B32).

Only observation/adjustment I'd make is that I'd remove the feeder tube from the expansion tank rather than bending/stressing it - I've had one crumble in my hands before.

 

Its a tad primitive. Its no wonder they changed to the Siemens on the B32

Good point on the tube. Mine doesn't seem bothered, but I made sure to unhook it further down the engine bay so it could move and not bend.

[qube 3570]

im so curious as to what the idle problem is.. 

[KwS 2425]

15 minutes ago, qube said:

im so curious as to what the idle problem is.. 

Not the only one!

Realistically it's not that bad, a slight stumble when warm and lumpy when cold. Just bothers me not knowing what it is!

[Secniv 182]

13 hours ago, KwS said:

Not the only one!

Realistically it's not that bad, a slight stumble when warm and lumpy when cold. Just bothers me not knowing what it is!

Interestingly Kelvin your old M3 has a lumpy idle around 600-650 when warmed up and no stumble. A bit hard to start when warm if you don't give a pre-start pump of the accelerator. Must check icv when I strike up the nerve to remove intake manifold or do you recall checking icv when you had it? 

[KwS 2425]

Interesting, that one idled like a dream. I recall I had the intake off at one point but dont remember why. Be worth checking the ICV and its piping. Also worth checking fuel pressure as that warm start issue is usually a sign of the fuel pump one-way valve failing and bleeding all the residual pressure away. Easiest to test the fuel pressure from under the car, at the outlet of the fuel filter, rather than trying to get at the fuel hose at the back of the rail.

In regards to the current one, I tested the fuel pressure today. The FPR is rated at a max of 3BAR (43psi). At idle, with the vac line attached, I had 50psi. With the vac line attached, according to the manual, I should see 6-10psi less than 43psi at idle, so should have about 35psi or so. New FPR is on the way, so will see what happens when I replace that. Fingers crossed.

Edited June 3, 2019 by KwS

[Olaf 3321]

Have you replaced the DME relay?   If it has 200+k kms and 25 years on it, those contacts have had a lot of current through them, could be a bit tarnished and worn.  Same for fuel pump relay.

EDIT:  Context for this comment is my e30 325i back in Blighty had hot start issues, and some very unusual behaviours.  Diagnosis with the RAC callout tech suggested new fuel pump relay.  This sorted the hot start.  Then I delved into my Bentley manual, and did some reading on line (back in 2001 there were some very helpful e30 sites), and came up with DME relay.  Sourced one, installed, issues resolved.  I guess clean power to the DME helped.  At the time the car was 13 years old with about 130k mi on the clock.

It's a relatively inexpensive part, worth a crack.  Hope that helps.

Edited June 3, 2019 by Olaf
Context for DME relay comment

[KwS 2425]

I havent, but will keep it in mind. My only issue is the rough idle, it starts first pop hot or cold. Will see what happens with the new FPR and maybe do the relays anyway later.

[bradgalbraith 218]

How's this coming along Kelvin? Any updates?

[qube 3570]

pretty sure hes sold this on?

[KwS 2425]

Yup, sold it back in June before i went overseas on holiday, to someone that randomly contacted me after I had stopped listing the car. Nothing I did fixed the idle issue, and the new owner wasnt bothered by it. Sold for 12 or 13k, as is with no reg/wof/cert. Should be up in Auckland again, and getting a widebody.

Edited September 10, 2019 by KwS