Piston Slap: Metering a Prince's Air Flow?

TTAC Commentator haroldhill writes:

Dear Sajeev,

My wife is driving (and loving) her 2009 MINI Cooper which has been a delight and remarkably trouble-free for 10 years. However, it recently developed a problem which has befuddled us and our highly reputable independent mechanic as well.

Under certain conditions the engine stumbles, feeling somewhat like an erratic misfire on one cylinder or fuel starvation; however, the stumbling vanishes when accelerator load is increased. The required conditions are: fully warmed up (10-15 minutes of driving), engine speed between 2700 and 3300 rpm, and light throttle appropriate to steady cruising. The stumbling will eventually bring on the “check engine” light and a P115C error code (Mass Air Flow).

If the engine is turned off for a few minutes (e.g. for a highway rest stop) the stumbling will disappear and won’t reappear until the car has been driven for another ten minutes, suggesting the fault is something remote enough from the engine that it can cool substantially in five minutes. After a few uneventful driving cycles, of course, the “check engine” light turns itself off. Thanks for nothing. On the other hand, this would be how I got it through emissions inspection…

Thus far the Mass Air Flow Meter has been replaced twice and the Throttle Body once. The latter seemed to help for awhile but I can’t be sure because it’s only recently that I’ve pinned down the exact conditions that will reliably bring this problem on. My wife, who does most of the driving, is a bit of a leadfoot and generally has much less trouble with this stumbling.

Our wonderful mechanic would appreciate any ideas or suggestions.

Read more
Piston Slap: E39 M5, Labor of Lust?

Still The Ultimate...

Jul writes:

Hey Man, I’d like to have your opinion: What do you think of the E39 M5?

Let me rephrase: What would you think about a 98000 miles absolutely mint condition, owned by an older gentleman with 3 or 4 other cars (the E39 not being his daily driver), with VANOS changed, clutch changed, and everything that could break down been changed as a preventive measure, E39 M5? … For $15K?

Wondering if I would treat myself to a potential money pit here buying this beast (that I already test drove, I’m in Love) knowing that I will not be driving it more than…5000 miles a year for the next two years MAX!

THANKS!

Read more
  • FreedMike I was lucky enough to grow up in a household with the two best German luxury sedans of the time - a manual '81 733i, and a '75 Mercedes 450SE. The BMW was a joy on back roads, and the Benz was a superb highway car. Good times. And both were dramatically better than the junkheap American luxury cars Dad had before.
  • Wjtinfwb A Celebrity Diesel... that is a unicorn. Those early A-bodies were much maligned and I'm sure the diesel didn't help that, but they developed into very decent and reliable transportation. Hopefully this oil-burner Chevy can do the same, it's worth keeping.
  • Wjtinfwb After S-classes crested the 40k mark in the early '80s, my dad moved from M-B to a BMW 733i Automatic. Anthracite gray over red leather, it was a spectacular driving car and insanely comfortable and reassuring on long interstate hauls. My mom, not really a car person, used the BMW to shuttle her elderly Mom back home to Pennsylvania from Miami. Mom and grandma both gushed with praise for the big BMW, stating she could have driven straight through the car was so comfortable and confidence inspiring. A truly great car that improved through the E38 generation, at which point the drugs apparently took hold of BMW styling and engineering and they went completely off the rails. The newest 7 series is a 100k abomination.
  • Vatchy If you want to talk about global warming, you might start here: https://en.wikipedia.org/wiki/Darvaza_gas_crater
  • 28-Cars-Later $55,218 for a new GR Corolla: https://www.reddit.com/r/COROLLA/comments/zcw10i/toyota_needs_to_know_the_demand_is_there_but_this/"But if OTD prices get beyond 50k there are better options"That's what people were arguing in that thread.