Piston Slap: Not Totally Enamored With E39 Upkeep?

Sajeev:

I was recently greeted with the warm, orange glow of a check engine light on my 2002 BMW 530iA with 93,000 miles. I took the car to AutoZone and had the code read. It’s a P0741, which indicates a failing torque converter. This is apparently a common issue on E39s with the ZF 5 speed automatic, as the seals in the torque converters tend to deteriorate.

Although it could also indicate other problems, I think this code probably means I have a transmission problem, as I’ve been experiencing some strange lock up behavior, especially on the interstate where the car will lurch and the revs will jump when I accelerate in fifth gear. I have an appointment at a local independent mechanic in a few days, but I’m not looking forward to hearing the diagnosis. Here’s the question: should I bite the bullet and spend $1200-$1800+ for a new/rebuilt torque converter to be installed, or do I sell the car and spend ten grand or so on a mid 2000s Honda with 80,000-100,000 miles?

I do like the Bimmer quite a bit, but it’s an expensive car to maintain, and I’m not totally enamored with the idea of spending so much time at the mechanic in the future. I’d be perfectly happy with a less luxurious Honda, but I would take a hit on the money I’ve put into this car already (new cooling system, some new suspension components, new MAF sensor, etc.)

Sajeev answers:

Can it really indicate other problems? I always thought P0741 is about ye olde torque converter…or a bad circuit between the lock up solenoid and engine computer. Plus, your “strange lock up behavior” on the highway proves my point.

Odds are you need a new converter, maybe the solenoid plus miscellaneous bits your mechanic will spot when the E39 is on the lift. And since you aren’t especially thrilled with owning a fantastic car with Germanic levels of wallet molesting…well…

Enjoy your new Honda. You’ll be far better off, even if us car peeps wish you’d keep the E39.

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.