Mechanics

MIS-FIRE, AND TIMING CHAIN TENSIONER

2000 BMW 540i

Engine Mechanical problem
2000 BMW 540i V8 Two Wheel Drive Automatic 170xxx miles

2000 540iT
Car: 170, xxx miles
Motor: 64, xxx miles (long block rebuild)

Greetings.

I'm getting a cylinder 1 and cylinder 7 mis-fire when attempting to do any real acceleration (merging in traffic, on-ramps, etc). However, I am un-able to replcate this on-demand. The car was a private party sale, and I've had a pre-buy inspection done. I've had the car for about 2 weeks.

In the inspection, it was noted that the valve cover gaskets are leaking, and the timing chain tensioner needs replacement. I've tried to be reasonably gentile, but if I didn't care about performance, I'd use my '89 accord as a daily driver.

Plugs were done at 170,006. I've checked all 8 coil packs for engine oil in the pack/connector. Most recent attempt (0 miles ago) was swapping packs 1/2, and 6/7. I have not yet driven the car, though it does start w/o error.

The timing chain tensioner looks fairly straight forward, but I'm concerned about skipping teeth, or putting excess tension on the chain. Thoughts?
Avatar
Chubblez
July 14, 2010.




The work you are looking at taking on is quite involved, do you need to have some coaching around that? If you have not done internal work on the M-62 motor, you may wish to seek out a tech that has experience.

Dr. Hagerty
Jul 15, 2010.
From the reasearch I've done the timing chain tensioner didn't look overly involved. Er, well, no more so then plugs or a compression test.

It would appear that I'm missing something, however. Any input you can offer would be greatly appreciated, Dr. Hagerty.

In a strange twist of events, I now have a donor vehicle as well. It's a 2002 540iT. It was a my daily driver before it was rear ended and totaled. My understanding is that most of the major parts (motor, transmission, etc) are interchangable.

Tiny
Chubblez
Jul 15, 2010.
The M-62 motor at the mileage suggested is prone to issues internally and not just the cam rail tensioner, the cam chain rails are somewhat fragile as they mature and the gasketing material BMW has wisely(?) Chosen to use has a definite lifespan, I recommend caution in your diagnosis. The noise, if indeed is just the tensioner and not the rails, then it is an easy job for most and perhaps not outside of your skill sets.

Dr. Hagerty
Jul 15, 2010.
My incliniation at this time is to take the car to BMW NW and have them look at it. To that end, I have an appointment set for Friday the 23rd.

Though sense I've change coil packs (1< -> 2, 6< -> 7) I'm now getting a mis-fire on cylinder 4.

What kind of internal work were you thinking needs to be done?

Tiny
Chubblez
Jul 15, 2010.
I it hasn't already been done, valley pan, valve cover gaskets, intake plate profile gasket and PCV plate, a bulletin about loose oil pump bolts, and several software related problems. This represents the big stuff, the little stuff like window regulators is next.

Dr. Hagerty
Jul 15, 2010.
In 2007 BMW NW put a Bavarian Auto rebuild M62 long block in the car. Is this something that would be normally done in standard maint?

Tiny
Chubblez
Jul 15, 2010.
So, I figured I'd post an update.

Having received the car back from BMW NW, I had the following work done - Valve cover gaskets, thrust arm bushings, oil change, coil pack on cylinder 1 & 7, battery, and alternator.

I've also done tires, because someone cut mine.

Tiny
Chubblez
Jul 29, 2010.
Thanks for the update, how is the car now?

Dr. Hagerty
Jul 30, 2010.
>: ) Fun
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Tiny
Chubblez
Jul 30, 2010.
All good

Dr. Hagerty
Jul 30, 2010.

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