XSeries-forum

Ive bought another E53 4.4 2001 and have only had it a week. It was cheap so i expected a few things to sort. It has a fsh
Anyway, I am not sure if it has a bit of a misfire so ideas please.
If i drive it steadily in any gear at about 1500-2000 rpm the engine seems to cut out / hesitate for a fraction of a second every minute or so. The rpm drops about 50-100rpm but then goes back up to what it was before. Its so quick it's barely noticable.  I tried to replicate it on the drive but it didnt do it. Only when actually driving the car.
There are no codes stored and it starts / idles ok. Fuel consumption is ok.
On the odd occasion when gently accelerating, again at between 1500/2000rpm, the car shudders for a few seconds. If I accelerate a bit harder it will not do it.
Can the plug coils fail on a certain load/ engine speed?  Could it be fuel related?

Any ides are welcome. Thanks

Nobody got any suggestions? I'll have to get a diagnostic done I think..

Ive been diagnosing it myself.. I think it may be transmission/torque convertor trouble. Every now and then i get a judder circa 1500rpm @ about 30-40mph. I dont think the TC is locking up (not sure if it is supposed to) in top gear when cruising at about 50-60mph. I think it's momentarily jumping out of drive but only for a fraction of a second which feels like a misfire. It only does it when up to temp so could poss be trans fluid/pressure related.
If anyone has experience or ideas please feel free to post.
I want to fix this as the rest of the car is really good (apart from drivers door mirror-grrr) and i dont like giving up.

If you have access to diagnostic kit it should be possible to get a transmission code read.  I had no warning lights with mine but the fault code showed 2 clutch packs and a brake pack failure.  In my case it was a TC failure that triggered the disaster (it all happened in seconds with no pre warning).

Yes the lock up clutch should work.

Hmm. I'll put my C110 on it tomorrow to see what's there. I may just do a fluid and filter change anyway. £150 and a few hrs under the car may just be worth it...