To; 'Eggraid' re 740i rough running ? ! !

so as to benefit as many folks as possible with your common M60 running problem, please POST it so anyone can read your question and my thoughts on a resolution. as i've requested before, on common problems like yours, i prefer my ideas reach as many as possible with the least amount of keyboard time [or i really couldn't do this stuff] thanks for understanding............jb.

Hello All,

I had the code 1222 come up for a while on my 1993 BMW 740i. If I reset the codes, I could drive for 3 days or so perfectly. I have gone through this cycle twice now.

One thing this car has done for a while is on cold startup, really buck and idle rough, until you tap the gas a little and it would clear right up. (this may be related to a minor fuel starve problem though and unrelated to the CORE issue. I have tested the past few days leaving the key "on" for a few more seconds before cranking and the car is starting smoother. As though giving a few more seconds for the fuel pump to get the gas up there is helping.)

Most recently, the 1222 code hasn't been there for three days now, when for no reason at all while driving today, I got a 1213. This results in the car really bucking at idle (stop lights, etc.) and generally running rough. I have not reset the code yet as I would like to see what the group suggests.

I have looked, for what I know anyway, for vacuum leaks--obvious things like a vacuum hose pulled off, etc. The first time I examined the engine, I saw that the idle control valve seemed to not be seated into the throttle body as tight as it should--fixed that. Is there anything else I should look for that could cause a "lean reading?"

Thanks in advance for your help,

Egg Raid

thanks, i'll be back soon................jb.

i'm interested in how your pulling and clearing your DME codes, before proceding.....reasons will follow and sorry i didn't ask earlier, i'm still getting out of laid-back vacation mode.........jb.

I am pulling the codes via the CEL "5 pump" method with the key on and tapping the accelorator. Using the Bently manual for reference.


I was "clearing" the codes rather novice-like by disconnecting the negative battery cable. I tried to clear with the pump method to no avail--probably because the problem was still there, eh? :-\

okee, doekee, [sorry], OK....i try to be cautious relpying to these queries since i do this to help frustrated or inquisitive owners/do-it yourselfers, NOT OTHER TECHNICIANS.............as you may have found out, both codes are 'mixture out of range' faults but w/o a DIS tester, MoDiC or GT-1 unit, you don't know if it's rich or lean condition. to me, your symptoms and codes are problematic of a failing 'crankcase pressure control valve' located in and part of the rear intake cover. the diaphram cracks over time and symptoms can vary widely with temp., etc...to a worst case of barely running and blowing heavy blue [oil] smoke out the tailpipe and loud squealing sounds from the engine.
both are due to the extreme drop in crankcase pressure, caused by the failed valve, which literaly sucks oil into the combustion chambers from places not designed for such low pressures......the 'howling' or squealing' noise is ait being drawn in through the front or rear crankshaft seals...............hope this helps..................jb.
p.s....the 1222 is for the right bank, the 1213 is for the left side.....AND..... if the problem has gone on to long, i have seen the cam cover gaskets get sucked in a cause additional leaks but one step at a time....................jb.

YOU 'DA MAN...

Indeed, I failed to mention the loud squealing noise that also begins when the CEL comes on and the car is idling. FANTASTIC, this really gives me something to start with and I will be sure to keep you and others in this forum updated as to the results of my (and your) efforts.

I really appreciate this!

ER

good fortune to you................jb.

Too bad the Bentley manual does not help too much in this regard. I have posted on their site to see if there is anything else in the way of removal/replacement instructions. Might be a situation of simply buying the part and getting a good look at it.

ER

You called it: 'crankcase pressure control valve' and I found only a very small reference to a crankcase pressue ventilation valve, which I am assuming is the same thing. Would you agree?

Also, my online part searches aren't showing either. Would there be another name for this part?
Thanks again,

ER

try 'rear intake manifold cover'....here's a list from my head, i'll try to post the part #'s by Tues.
a. rear intake cover
b. " " " gasket
c. small vacuum plug
d. large " "
e. (7) cover bolts [ 6X20mm i think ]

THE big problem in replacing the cover with the manifold on the car is straight/square/axial access to the lower (4) [i think] cover bolts, [ on the rear of the intake manifold ]. you'll need fresh[new] 'male' TORX socket T25 or T30 [i'm home now and can't recall]. the trick is not to 'round-off' or damage the bolt heads trying to loosen them and they'll be tight.........personally, i usually remove and reseal the complete intake manifold since all the gaskets are the same material and will harden and leak with age...........it might be easier for me as i do this repair often and want to do a thorough job for my customers after explaining the + & - 's of the two options..........sometimes complete removal is required when the cover bolts won't loosen but this is rare...........jb.

jb,

Sorry to bother you on this again. Have you by any chance located the part numbers on this? This would be a huge help for me. I unfortunately am not getting the help I require from the local BMW parts department.

We bought this car in January, and this will be the first time I really "dig" into the engine. Past experiences are both Dodge and Ford pick-ups! :) A change I know, but shouldn't be too bad with some patience.

As a reminder, the car is a 1993 740i, M60.

Best,

ER

sorry i left them @ work ! ? * # % ! I'll post them on 6/28/04 for you ! enjoy the weekend...........jb.

i made a new post with all the PN's you'll need, soory for the delay. best to you!.....................jb.

For the record, The car has been repaired as advised in this post, and it is running stellar! Thanks for the great advice. Driven for the past few days to ensure the symptoms don't return--none so far.

EggRaid

wish you the best......................................jeff b.

JB you are a GURU!!! I had the same exact prob. w/my 1995 740i, and if im not mistaken i got that troubleshooting tip from 1 of your posts.THANX if it werent for real knowhow guys like yourself i my have sold my car. Ive also got a 1998 540i and if anything goes wrong again ill look you up