IX Running Rough...

[95BMWIC]

Son came home from college - I had a few things to do on his car and I thought I could get through them in one day (speedometer gears and rotate tires). So I was a bit surprised when I jumped in the car to move it in the garage and the car was running rough..

It sounded like it was misfiring..

So I pulled the air cleaner, checked vacuum hoses and found a cracked crankcase to throttle body hose.. but I'm pretty sure that wasn't the complete issue..

I pulled the plugs and found that #5 was fouled up.. as you see in the pic the others weren't fouled and were all in similar shape.


So what can cause this?

[95BMWIC]

I plan on getting the proper Bosch WR8 plugs (the one that were in there are the Bosch platinum's)..

I pulled the cap and rotor.

Cap looked like normal wear..

The rotor looks like this.. A bit rougher around the edge than expected..

[95BMWIC]

Cap pic...

(Damn these things are expensive)


Car idled - didn't die.. didn't sound like a vacuum leak sons been driving it to work like this for a month or so (according to him).. ICV seemed ok - could hear the rattle.. Brain is a bit foggy this winter.. (so I thought I ask)

Anything else - that I could be forgetting? Or anything else to check?

[spdracrm3]

My 240k IX does this also (uses a quart between oil changes) alway #5 plug I just clean it and rotate it into another hole ,runs fine again
makes me wonder if that hole didn't get bored/honed properly or runs hottest a wears piston rings out faster than other holes

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[95BMWIC]

My 240k IX does this also (uses a quart between oil changes) alway #5 plug I just clean it and rotate it into another hole ,runs fine again
makes me wonder if that hole didn't get bored/honed properly or runs hottest a wears piston rings out faster than other holes

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Odd- Thanks for that..



I went ahead and ordered a couple of rotors and caps and 2 sets of plugs from BAVAUTO - the prices were better than Pelican and e-euro with the Cyber Monday and all.. might as well stock an extra set - since I own 3 E30s.. :(

[spdracrm3]

Just ordered front bilsteins and swaybar bushings for mine using that BavAuto sale, good deals, been waiting for this sale

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[EyExR]

Leaking valve cover gasket or cam plug can cause this. Or bad rings or valve guides? I would pull the valve cover and put a new one on with a little rtv at the plugs and corners. You might want to do a compression test and leak down to rule some things out.

[95BMWIC]

Leaking valve cover gasket or cam plug can cause this. Or bad rings or valve guides? I would pull the valve cover and put a new one on with a little rtv at the plugs and corners. You might want to do a compression test and leak down to rule some things out.

Good suggestion - I will try that this weekend - I think I have an extra gasket lying around (and some cam plugs).. I'll check compression then too and report back...

[berlow94]

Because of the harmonics of these motors, #5 will always be the first to show any signs of problems. Wether it be bearing wear, loss of compression, valve guides, etc...

[EyExR]

Good suggestion - I will try that this weekend - I think I have an extra gasket lying around (and some cam plugs).. I'll check compression then too and report back...

And if you could get it smoked I would. Rule out all your vac leaks as well.

[95BMWIC]

Paid a little extra for BOSCH.. and here is what I get..

Anyone ever seen this before... ?

:giggle:

Thankfully I ordered 2 -and can complete my son's tuneup this weekend..

[95BMWIC]

Update.

Finished installing all the components I ordered (Plugs, Cap, Rotor, crank case vacuum hose). I also cleaned ICV valve.

I also ran a compression check across all 6 cylinders - All were 150+ and held..

The car ran great after that..

Not sure what to think..

[squidmaster]

Glad you got it working! At this age the e30s can be finicky at times