Yet another victim of Nikasil...sob.

[uberhahn]

I just bought a '94 530i. 91k miles. Rough idle. No vacuum leaks. Bought for steal. Just took to dealer to investigate idle. He's doing the test today.

I'm hoping for some positive news.

-uberhahn

[DueyT]

Ask for a hard copy print out of the leakdown test, then come back here. If he just does the diagnostics test through the DME, I wouldn't be so quick to send the car to the heap.

How long has the rough idle been happening? With the colder weather? How doest the car start? Extended cranking, difficulty starting, etc...?

Cheers
Duey

[George M]

sounds like a suitable candidate for a 4.0L transplant.
The American thing to do :p
George

[bimmerd00d]

bored 4.4 liter, i smell a 4.6-4.8 stroker :-D

[George M]

even better ;)

[uberhahn]

Ask for a hard copy print out of the leakdown test, then come back here. If he just does the diagnostics test through the DME, I wouldn't be so quick to send the car to the heap.

How long has the rough idle been happening? With the colder weather? How doest the car start? Extended cranking, difficulty starting, etc...?

Cheers
Duey

They're doing a full leakdown. I will scan and post here as I get it. The cold weather has really brought the prob out. Starts just fine, very little cranking. However it will not hold at idle. Stalls immediately without throttle input. As it warms, it gets better, but I still can't coast in neutral, or at a stoplight.

uberhahn

[DueyT]

If it always did that for you, then Nikitis may be an issue.

If, however, its undrivability/idleability only became unacceptable after the colder weather really set in, I'd be betting on a cracked inlet manifold gasket or the PVC plate...

My 2 ¢

Duey

[Johntee540]

The Cold weather Onset bothers me. I am betting more than $50 its a vacuum leak. PVC Plate or intake Manifold gasket. If it ran fine when weather was warm then no reason to expect a sudden onset of Nikititis. These things are often mis diagnosed. At this age these cars have more Vacuum leaks due to organic failure than block failure. Who wants to bet? - JT

[MarkD]

If it always did that for you, then Nikitis may be an issue.

If, however, its undrivability/idleability only became unacceptable after the colder weather really set in, I'd be betting on a cracked inlet manifold gasket or the PVC plate...

My 2 ¢

Duey

Or it could be running too rich when cold. May need to change the coolant temp. sensor.

[winfred]

throw in a clogged cat on one side with a blown plate and they run real good, or a weak fuel pump. disconnect the battery for a few minutes reconnect and start it and see how it runs, if it is a leak it should run better


The Cold weather Onset bothers me. I am betting more than $50 its a vacuum leak. PVC Plate or intake Manifold gasket. If it ran fine when weather was warm then no reason to expect a sudden onset of Nikititis. These things are often mis diagnosed. At this age these cars have more Vacuum leaks due to organic failure than block failure. Who wants to bet? - JT

[wengenstein]

werd


The Cold weather Onset bothers me. I am betting more than $50 its a vacuum leak. PVC Plate or intake Manifold gasket. If it ran fine when weather was warm then no reason to expect a sudden onset of Nikititis. These things are often mis diagnosed. At this age these cars have more Vacuum leaks due to organic failure than block failure. Who wants to bet? - JT

[George M]

the dealer will want to sell you a new motor. I would be very leary of anything they tell you. I may even be distrustful of any leak down results they provide unless you know for sure they were from your motor. You are much further ahead if you are mechanical and own an aging bimmer so you can do the work yourself. Even money it is not a worn block but other issues addressed in this thread. Whatever the problem, you have 20% chance of getting the straight story from the stealer.
Good Luck,
George

[DueyT]

I echo George's sentiment. Kind of water under the bridge, but I'd have a leakdown done by an independant...not the stealer. Not to hack on the dealers too bad, some of them have little pockets of cools guys that love the cars, but I think it's fair to say, overall the servicing mentality is to help out the profit margin primarily on the backs of well off folks who buys these cars off the showroom floor. I know there are exceptions, but they're well hidden. As well, as George notes, these cars are getting to an age where a whole host of issues start popping up just based on age of components, kind of like a wave right about after you've gone through two suspensions...

Cheers,
Duey