So I have had my 2006 MCS about three months now. Yesterday was a pretty hot day about 100 degrees. So here's what happen.

Leave to go grab some lunch. Went through drive thru leaving parking lot turning right and all the sudden stepped on throttle and no power all lights came on. About a mile later at five mph of driving the battery light goes off. I limp it back to the house I was working on. Shut the car off turn it on and it runs fine.
After work start it up and drive to the mechanic with no problems only light that's on is the service engine soon light.

Mechanic hooks up the car to his scanner and couldn't get the car to register. We unhook it start it up and the SES light is off. Drove home like normal without any issues it ran like normal.

No all I can hear different it a slight belt squeak. Other than that it's running perfect. Any ideas ?

 

Gremlins!
...but I digress.
Broad spectrum electronic anomalies generally indicate a battery on it's last legs, the ECU pitches a total fit when it starts to die. The next obvious question is fuel. Are you using nothing but top tier 91 octane or higher? Improper fuel will eventually smoke the knock sensor which will throw codes and turn on lights. Don't know if either of those is much help but they represent the more common causes of error codes.

 

The battery is brand new it died the second day I had the car. My wife does drive the car and told me when she filled it up for me she put regular gas in it. I guess I could add an octane booster to that tank but I would think that regular gas would just get worse gas milage ?

I reset the computer but now am just a little worried pulling into traffic now for a whole since I can't find anything wrong. The belt is squeaking so could be another component or just the belt maybe.

 

The Service Engine Soon light won't throw a code right? Just if the EML light is on which that is off.

 

When that happened to Artoo, my 2003 MCS, it was the BPV. But turning it off and then restarting brought it out of limp mode.

That said I am not sure how you check the BPV and what code it would have thrown.

Happy 4th everyone!

///Rich

 

I'm not sure what that BPV is ? Guessing maybe a back pressure valve for the supercharger maybe.

 

Bypass Valve. It sort of looks like a throttle body. I replaced mine with a stock one but lots of people like the Detroit Tuned one with a heaver spring and also adjusted to close tighter.

The OEM is a bit over $100 and takes an hour to replace. But I am not sure how to tell if that is “your” problem. Helix used to have a video of how to replace it which seems not to be available any more. :-(

Rich

 

Something is squeaking under there. Just a little. I am gonna research the symptoms of a failing supercharger just to rule that out.

 

My '05 MCS did the limp mode right when about coming back a parking garage in SC. Now I'm to Lincoln for a packing to move there. She's in the university garage parking. It went to LIMP mode and service engine light came on, not the check engine light. I stopped and checked all, then started up,and it ran fine for only a few miles until I got to the parking garage. Then it happened again. Not sure what's going on. I can't check the dam thing for 2 weeks. What do I look at?

 

Always look at the crank damper....sometimes when it slips the sudden loss of boost will cause limp mode...then it cools....grabs...
Other possibility is the sc boots can leak...cause an issue....
Still...check with an odb2 reader....codes will help tons in pinning down the issue.

 

P.S.
Using "regular gas", aka 87 or even 89 octane can cause several thousand dollars in damage to the valves....
Good luck.

 

This is great to check too. I'll finally get to see her in 2 weeks. Sad! She's just in the parking garage. No worries though, coverd and paid for.

We'll hope for the best!
Wow! I miss the drive taking the Rav4 and Camry out getting ready for the next drive to SC from NE> Booooorrrring At least they're running fine.

 

Zippy nailed it. I had a major failure today while trying to figure out what was wrong. Belt locked up and then limp mode. Pulled over checked and it was barely spinning. Was a couple blocks from home so limped it back. Started it back up at home and the harmonic balancer has come apart.

Now for the bigger question. Do I just take it in me warranty the work or do I get the balancer and swap it out myself ? I'm guessing this has been the issue because the car has done exactly what Zippy described.

 

Pretty common with the OEM part....
The prw gel damper and the ati superdamper are options..
About $350-450 for the part and maybe an hours labor.... OEM is similar...then add s $30 belt....
Getting the old one off can be a pain....but if you do not diy it. 100% get a tow...

 

Zippy I was looking at the Super Damper and was wondering if the 2% uses the stock length belt ?

Obviously the puller is needed to get the old one off but how does the new one get pressed on ?

 

Yes you can use the stock belt with the 2% ATI damper.

The ATI Damper comes with a longer bolt and fat washer to help you pull it onto the crankshaft. Not a bad job to do. And you'll even notice the car will idle smoother when you install the ATI.

 

I ended up getting the PRW pulley.

 

Zippy! You're great! I think this indeed may also be my problem. Can't wait to get out there and do it. I'll get a good mechanic rather that diy. I'm a piano technician, not a car guy. Just love to drive!

 

Pno2nr , mine was going straight into limp mode , lights would come on and the battery light was on and off depending on when the damper was grabbing. Smell of burnt rubber was a definite. Just FYI

 

hmmmm. No battery light and no burnt rubber smell that I could detect. Maybe something completely different.