Jump to content
goosiegander

Vacuum issue m50? Solved =Dead coil pack!

Recommended Posts

Hey Guys!

 

Rough running, idle, and power loss over 2/3 throttle...

 

Hoses had perished in places so fixed that in good old pikey fashon, however,

 

http://bmwfans.info/parts/catalog/E34/Touring/Europe/525i-M50/RHD/M/1996/may/browse/engine/intake_manifold_system/

 

Item 9, the connector in the link feels loose and will wobble easily,

 

Saw other threads suggesting that plugs may cause running rough...

 

How screwed am I?

 

Is there an exhaustive list of items to replace to eliminate vacuum leaks?

 

TIA

 

Chris

Edited by goosiegander

Share this post


Link to post
Share on other sites

Temp behaving 

 

Plugs currently unchecked,

 

Throttle boot sealed up along with the two lower hose connections, the solid pipe in the link is wobbling in my hand, figure thats it as you can hear the whoosh as the throttle is blipped now...

 

:(

Share this post


Link to post
Share on other sites

As No.9 is wobbling, looks like its manifold off time, new seals/gaskets all round (you have to replace manifold seals anyway if the manifold comes off).

 

I would replace No.9 as well, it may be broken, more to the point, I wouldn't be taking everything off, save a few pennies by not replacing it, put everything back together again, only to find it still wobbles.

 

Also I would recommend changing all the air intake hoses from the MAF onwards, the vac hoses and the fuel hoses while you have easy access to them.  Give the idle control valve a clean, don't forget the vac hose to the fuel regulator as well.

 

As you have access, you could also change all the sensors over if your budget allows. 

 

Why do all this?  Well my vac hoses had perished on my 200K, 21year old iX so it was manifold off time to get access to them, in fiddling around, my mechanic moved the front fuel hose and that hose subsequently started leaking because it was so old and stiff. In the end, I just felt it was easier to eliminate all potential problems by changing sensors over replacing all gaskets/seals and changing all rubber hoses.  It didn't add up to a lot but the result was a smooth running engine performing to spec.

 

I would still check the plugs and when did the car last have a service, e.g. filter changes?

 

Thinking of other things, check the oil filler cap seal, again cheap to replace, what state are the rocker (cylinder head) gaskets in, etc, etc?

Share this post


Link to post
Share on other sites

Chris,

 

that connector between the manifold and ICV should be rock solid, my newly fitted one certainly is when I prod it (can't get my hand round there) which suggests that (1) the gasket, item no.10 has perished (likely) or (2)  the connector has broken (unlikely) or (3) the manifold has cracked (very unlikely).

 

It may also mean that item No.8 in this diagram, the manifold to ICV hose has perished, http://bmwfans.info/parts/catalog/E34/Touring/Europe/525i-M50/RHD/M/1996/may/browse/fuel_preparation_system/mass_air_flow_sensor/

Edited by Dongiov

Share this post


Link to post
Share on other sites

Thanks for that Geoff!

 

Plugs changed and idle stabilised slightly, correct NGK's were fitted but the usual gunk at the coil pack bases.

 

All vac hoses including plastic T attachment and gaskets for this/manifold to come off ordered for friday delivery at cooper ipswich, Friday evening should be fun...

Share this post


Link to post
Share on other sites

Does that mean you are going to change the rocker gaskets as well?

 

Keep the old stuff, if you come to sell the car, put it all back on again and keep the new stuff for your next M50.

Share this post


Link to post
Share on other sites

Indeed so Si,

 

Well the new gear is here and the inlet manifold is almost off,

 

Hoping to see horrific vac hoses otherwise its going to need further investigation, pictures of carnage shortly :D

Share this post


Link to post
Share on other sites

Right all thats done, no vacuum leaks so far as i can see/hear,

 

Had fault codes read, came back with TPS which was cleared and stayed cleared...

 

All i can think now is Fuel filter,

 

Any other thoughts?

Share this post


Link to post
Share on other sites

Why was the manifold to ICV connector moving?

Figure It's just the rubber section that was moving and my lack of experience with the M50

 

That should be the Vac leaks eliminated now, could be fuel P/P, cam/crank sensors, fuel filter, worst case ECU... and as Si mentioned MAF though when unplugged the engine

just dies...

 

Does seem worse in hot weather...

Share this post


Link to post
Share on other sites

MAF swapped, Lambda unplugged, Fuel filter changed, codes read all that came up was the knock sensor...

 

Fuse 30 was melted, so replaced, no joy...

 

Earth to the fuel pump was checked and bypassed, no joy...

 

Still misbehaving!

 

Fault codes clear...

 

Steven I still haven't changed the fuel pump over, had a go at releasing the spare but no joy, thinking it may be easier to swap the tanks!!

 

Behaviour seem slightly better with engine in a cooler environment, also with aircon off and less electrical load placed on the car by sterio/fan

 

Could it be a relay?

 

F**king car!!! :(

Share this post


Link to post
Share on other sites

Cats don't look new to be fair,

 

Car dead now, idles like a pig and won't rev. appears to be temp related as this morning 10+ degrees cooler in the shade it got me to work just fine...

 

Overfuelling as well by the smell of the zaust gas...

 

Don't know about the valve or carbon arrangements dude...

 

More and more annoying...

 

:?

Share this post


Link to post
Share on other sites

charcoal canister, its plumbing, or the evaporative purge valve?

this cause my tank to suck in and crushedmy fuel sender.

Share this post


Link to post
Share on other sites

engine temperature sensor for the engine management- might explain temperature-related aspect?

Going to order one up!

 

Mine was probably new with the car...

Share this post


Link to post
Share on other sites

Going to order one up!

 

Mine was probably new with the car...

Unfortunately, you'll probably have to take the manifold off again to get to it..... :rolleyes:

Share this post


Link to post
Share on other sites

Unfortunately, you'll probably have to take the manifold off again to get to it..... :rolleyes:

After all that drama last time i think i'll just accept skinned knuckles...

 

Either that or pay someone to do it for me

Share this post


Link to post
Share on other sites

MAF swapped, Lambda unplugged, Fuel filter changed, codes read all that came up was the knock sensor...

 

Fuse 30 was melted, so replaced, no joy...

 

Earth to the fuel pump was checked and bypassed, no joy...

 

Still misbehaving!

 

Fault codes clear...

 

Steven I still haven't changed the fuel pump over, had a go at releasing the spare but no joy, thinking it may be easier to swap the tanks!!

 

Behaviour seem slightly better with engine in a cooler environment, also with aircon off and less electrical load placed on the car by sterio/fan

 

Could it be a relay?

 

F**king car!!! :(

Correction, it was actually fuse 25!

 

Its still fine today :)

 

Shame about the other tonne and a half!  :x

Share this post


Link to post
Share on other sites

Changed the battery at lunchtime to a spanking new bosch S5,

 

NO joy, still sub 500 rpm idle, no revving...

 

:(

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×