I'm looking at a 2008 MDX with 33K miles. The owner spends winters down in Florida, so when I picked up the MDX, it hadn't been run in a couple of months.

My first drive was about 45 minutes. No problems. Stopped for dinner and then got back on the road about 45 minutes later. As I was accelerating to get on the highway, the check engine light came on, and the multi-indicator display showed 2 errors:
1) Check Emission System
2) Check SH-AWD System

The 2nd error was accompanied by a verbal warning saying that, due to the AWD problem, the vehicle was likely running in 2 wheel drive. It also said to stop the car at my earliest convenience and shut it off to reset the error. Sure enough, shutting it down and restarting it cleared the error (and here I thought this was an Acura and not a Microsoft product ;-)). Anyway, the error has returned 4 times over the last 4 days...every time when accelerating. And the rear wheels definitely lost all power each time.

I brought it into the dealership. First, they told me that there were no error codes from the SH-AWD, and that the CEL (Check Engine Light) error was caused by a cylinder mis-fire. I can accept the misfire as being a result of the car having sat for a while...but when they said that there were no obvious problems with the SH-AWD, I reiterated that it happened 4 times in a week. They said that they would take it out for another test drive.

They called back an hour later and said that accelerating while the CEL was on caused the MDX to go into "Limp Mode", which shut down the rear wheels. After reading a bit about Limp Mode, I know that it exists...but can't info that would indicate one way or another if an emission problem and/or cylinder misfire could cause the rear transmission to be shut down.

I haven't actually bought the vehicle yet and can walk away from it...and I'm a bit concerned that the dealership's initial response was "there's nothing wrong". Does anyone out there have any experience with this kind of problem ?

I'd appreciate your feedback.

Thanks,
Jeff

 

Walk away.

There are many mdx's out there and they shouldn't be going into "limp mode'' or flashing cel's. Look for another one

 

Thanks for your advice !

 

I test drove a few before buying mine pre=owned. Some of those lease return cars are beat up, but if you take your time you'll find t he right one.

2008 at 31K miles is what I ended up with. Stayed away from the color white, as I seen many of them with lot damager and colors are mismatched.

 

Thanks Mr Wilson.
At this point, I'm walking away from this one...the dealership has had it for going on 3 days and, aside from the CEL code of a cylinder misfire, they say they can find nothing wrong with it.

I also posted on another forum, where a couple of people suggested that it was bad gas (from the car sitting around), and that I should have the gas tank flushed, plugs and wires changed, etc.

I still can't find any information about "limp mode" beyond that when it kicks in, it changes the fuel mixture so that it runs rough/slower so you can't damage the engine. I couldn't find anything about limp mode affecting the rear transmission. And even if it does, if limp mode is supposed to protect the engine AND transmission, why does the mode shut off after stopping and restarting the car ?

 

I wouldn't be suprised if it's the gas issue..my neighbors who have boats/atv's etc....are going nuts over teh issues with etheynol

 

***** I have experienced problems with ethanol and outboard motors...but that's with my 10 year old 2 stroke motor that was never designed to run on gas/ethanol mixes.

Honestly, I have to wonder whether I really would want a vehicle that is so sensitive that the rear transmission can shut down because of bad gas.

And I'm still a bit suspicious about being told that this was limp mode...what good is a "safety" mode like that if you can reset it by turning the car off and restarting it ?

In the end, it was a leased vehicle that I was considering. The lease is up, and I decided not to buy it, so Acura has it now and it will shortly be some poor, unsuspecting person's problem.

 

I bet the owner used regular gas all the time to save a buck or two and didn't fill the tank when he left for FL (How many winters did it set?); probably an old geezer who shouldn't own an MDX if he isn't going to drive it.

 

mdx emblems on front doors and oem all weather mats ? Really ? BWAHAHAHAHAHAHA
BWAHAHAHAHAHAHAHAHAHAHAHAHAHAHA
BWAHAHAHAHAHAHAHAHAHAHAHAHAHAHA