Piston Slap: A DHS, A Darn Hard Situation

Chuck writes:

My son enjoys being able to spread out when driving and also appreciates the convenience of hauling several of his buds around. He drives a 2001 Cadillac DHS. He has just moved to Massachusetts and registered the car there. It failed inspection with OBD codes P1860 and P0741. He has 60 days to resolve the problem. A little internet searching informs that these codes are related to the torque converter clutch circuit and the solenoid valve.

The codes may indicate anything from a bad electrical connection to a failed plastic solenoid (I hate plastic) to a worn TC clutch. Other than the not so likely electrical connection fix, labor is at least 12 hours, even for the solenoid. I don’t see this as an emissions or safety issue, but then I’m not the state of Massachusetts.

I see his options as: a) rebuild the transmission for from 1/3rd to 2/3rds (dealer platinum level rip-off) the value of the car , OR b) get an economic hardship waiver for a year and figure out what to do – an alternative is selling the car in a state that isn’t as awful as MA c) clear the codes and drive veeery slowly to the inspection station (mixed forum opinions on whether this could work). On the ethics of selling a car with a possibly dodgy transmission – he’ll disclose it and furthermore the transmission could stop working tomorrow or could last much longer, according to the Caddy forums.

I’ve taken that gamble in the past and won more often than I’ve lost. In this instance, many comments in the forums suggest the impact is likely just a 1 MPG penalty from not having lockup – BFD. You get that penalty from moderately underinflated tires.

Any other suggestions, beyond drive the thing into Back Bay? Moving is not an option, certainly not in 60 days.

Sajeev answers:

First off, you can’t clear the codes and pass inspection: the shop will notice the lack of data and ask you to come back after driving the car a coupla days. That’s the beauty of OBD-II electrics, you bow down before them, as you are at their mercy! Well, sometimes…

But that’s not the point. The economic hardship paperwork is your son’s best choice until he can find someone to dig into the transaxle for a reasonable price. If this was a 2001 Lincoln Continental with it’s less-well-known transaxle, I’d just give up and find a different car. That’s because your average transmission shop, for one reason or another, usually knows how to rebuild a GM transmission blindfolded. And other oddball trannies are, well, out of luck. You experience may vary, maybe I’ve just been that unlucky.

For sure, have someone examine the plastic connector(s), because that’s cheap and easy. Many transmission shops do free diagnosis, and a free quote to do the work afterwards. But no matter what, I always recommend a full rebuild if you’re going in there. Its just a waste of labor if you do not replace all the wear items when they dig in there.

My advice? Sell that ‘Lac to someone in the American South who could use a decent foundation for a Swanga. Just kidding. But only a little bit.

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry.