M3 Evo Vanos solenoids

[andye30m3]

Hi

Does anyone have and solenoids or a broken vanos with working solenoids?

I think my inlets ones are broken and would rather check this with a second hand set than buy new ones only to find out these aren't the problem.

Thanks in advance.

[teabagger]

i thought a specialist beemer garage (with the correct equipment) could run a vanos test which tests the solenoids.

this may be the cheapest way to do it in the long run.

[< FORZA WEST]

We can,I run the BM diag system which has the test program.

I would imagine a second hand vanos is like rocking horse stuff as they are exchange units

[andye30m3]

Will the test say if it's the solenoids or will it just come up with vanos failure?

I don't really want to have it tested to have it come back with a vanos failure with replacements at £1500-2000 when it could be the £200 solenoid which is broken.

[tjw110]

The soleniods are very easy to check if they have failed they will have gone open circuit. Take the bolts of the exhaust soleniod (you may need a new gasket) and stick an avo over the connections, it will read open or closed circuit. When my vanos unit went I was diagnosed with a faulty exhaust soleniod, I managed to get a set of second hand one's (checked em first) and replaced the soleniods (10 minute job) it seemed to cure the problem, but within 24 hours the problem was back (lumpy idle) Took out the soleniods and the replacment set had broken (Only one of the exhaust pair) I'd also lost the power increase at 2500rpm. The Vanos uint was shagged..!!! Got a new unit from BMW £1650 + VAT and a BMW specialist to fit it for £200 cash

Have you lost the power increase @ 2500rpm? and have the lumpy idle problem?

[andye30m3]

I'll have a look at that tonight.

You can see that the solenoid is damaged but wanted to check that was all.

The car seams to run fine after 2500 rpm but is lumpy on tick over and not great below 2500rpm.

[teabagger]

andye30m3 said:

You can see that the solenoid is damaged but wanted to check that was all.

how does it look damaged?

[andye30m3]

The very end where the smaller o-ring is has partly come away from the main solenoid so the smaller o-ring doesn't seal properly.

Its a bit hard to explain but its the bit on the end which forms the recess for the o-ring.

[Rupe]

andye30m3

This is exactly what happened to the exhaust solenoids on my M3 evo. I cured it by making up a bush for each which sat in the bottom of the housing to act as a new inner edge of the o-ring groove. I filed of the remains of the damaged original outer edge on the solenoid so that it sat inside the bush slightly. If you have access to a lathe then you could do the same, or look for some second hand solenoid units. New units are the other option at £210 per pair. If you are interested I could dig out the dimensions of bush you require. Check both solenoids read approx. 4 ohms from the middle pin of the 3 pin plug to each end in turn. If this is not correct then you will need to replace them anyway. In my view this is a design fault with the solenoids as the counterbore is unnecessary and comes too close to the bottom of the o-ring groove thus weakening it.

Rupe

[teabagger]

Rupe said:

andye30m3

This is exactly what happened to the exhaust solenoids on my M3 evo. I cured it by making up a bush for each which sat in the bottom of the housing to act as a new inner edge of the o-ring groove. I filed of the remains of the damaged original outer edge on the solenoid so that it sat inside the bush slightly. If you have access to a lathe then you could do the same, or look for some second hand solenoid units. New units are the other option at £210 per pair. If you are interested I could dig out the dimensions of bush you require. Check both solenoids read approx. 4 ohms from the middle pin of the 3 pin plug to each end in turn. If this is not correct then you will need to replace them anyway. In my view this is a design fault with the solenoids as the counterbore is unnecessary and comes too close to the bottom of the o-ring groove thus weakening it.

Rupe

this is good info but still hard to follow if as i, i have not seen the solenoids in the flesh.
how does the wear on the end of the solenoids cause the solenoid to fail and how does the bush rectify it?
http://www.realoem.com/bmw/showparts.do?model=BG92...

[andye30m3]

Rupe said:

andye30m3

This is exactly what happened to the exhaust solenoids on my M3 evo. I cured it by making up a bush for each which sat in the bottom of the housing to act as a new inner edge of the o-ring groove. I filed of the remains of the damaged original outer edge on the solenoid so that it sat inside the bush slightly. If you have access to a lathe then you could do the same, or look for some second hand solenoid units. New units are the other option at £210 per pair. If you are interested I could dig out the dimensions of bush you require. Check both solenoids read approx. 4 ohms from the middle pin of the 3 pin plug to each end in turn. If this is not correct then you will need to replace them anyway. In my view this is a design fault with the solenoids as the counterbore is unnecessary and comes too close to the bottom of the o-ring groove thus weakening it.

Rupe

Cheers for the reply, i'll check the resistance tomorrow, Would be very greatfull if you could find out the size of the bush as i know someone who might be able to make them up

Cheers andy

[wmg100]

There's one on ebay at the moment:

http://cgi.ebay.co.uk/BMW-m3-vanos-unit-FAULTY_W0Q...

(nothing to do with me BTW)

[joesnow]

I have a rough idle, and exhaust solenoid pressure problems (dealer diagnosed - new vanos required). I'm looking at changing the solenoid and all associated seals in the next couple of weeks. I'll keep my eye in this thread.

I have found this http://forums.bimmerforums.com/forum/showthread.ph...
this http://www.beisansystems.com/procedures/vanos_proc...
and this http://mukerji.co.uk/vanos/

which may be of use to you.

and here's something to ease the pain http://forums.bimmerforums.com/forum/showthread.ph...

Edited by joesnow on Wednesday 6th August 11:31

[Rupe]

Andye30m3

I read one of your earlier posts and see that you had vanos bolt failures, this is how mine started. I will find the bush sizes on Wednesday when I am back at work. Have you checked the solenoid resistances yet?

Rupe

[andye30m3]

Rupe said:

Andye30m3

I read one of your earlier posts and see that you had vanos bolt failures, this is how mine started. I will find the bush sizes on Wednesday when I am back at work. Have you checked the solenoid resistances yet?

Rupe

Cheers

I checked the resistances yesterday they came out at 4.5 and 4.5 for the inlet solenoids and 4.5 and 5.2 for the exhaust, not sure how significant the 5.2 is.

[Rupe]

Andy

The bushes I made were 17.45mm OD, 14.5mm ID and 6mm wide. I then filed off the rest of the partially broken outer edge of the o-ring groove so the the solenoids had just a square end that the o-ring would slip over. You may need to fettle the bore of the bush and the end of the solenoid so they just fit together with the o-ring between. I also needed to clean up the bores of the vanos unit where the solenoids fit as these were slightly burred up when the bolts had broken and the solenoids moved. You could come down on the OD of the bushes by 0.05 to 0.1mm to allow for any damage you may have, check the bores with your finger to see what they are like. I fitted all new o-rings and it has been working fine for nearly 2 years now. Incidentally I have just had a major blitz on my car, new rear brake pipes (the short 'S' pieces), new braided clutch hose and new lambda sensors. I will stick a post on here when I have done a few miles. Needs a major bodywork blitz next!

Rupe

[Rupe]

Andy

Forgot to mention, those resistance readings look ok to me.

Rupe