Hard shift, traction control service on, no solenoid codes
 

Just started doing this the other day when my wife was driving it. Traction control is off, says service traction, shifts hard--most of the time but not always.

CEL codes are only O2 sensor, evap solenoid, and Low MAS. changed the air filter and cleaned the MAS runs same, shifts same. Would I have to reset and clear the codes to get it to make a difference?

Could something that doesn't set a code cause this?

My apologies, 07, 2.4

Please get the codes reread and post them , sounds like maybe the VVT solenoids

Thanks. Do I need to reset before getting the codes reread?

No...and just post the numerical and letter codes.. Example, P0014 (note zero's not O's).

Ok. Will do. But it will probably be Friday before I'll be able to get back to it.

I was hoping it was the intake or exhaust solenoid but it wasn't popping those codes.

What about "CEL codes are only O2 sensor, evap solenoid," Where they supposed to be fixed by cleaning the MAF (not MAS I'm guessing)?

You might consider checking the fuses. You should make sure the MAF is plugged in correctly.

The VVT valves don't always set codes.

I didn't replace the air sensor. I cleaned it. It is plugged in properly and I cleaned the contacts also. Is there a possibility that the o2 sensor or evap are going to cause this issue? Otherwise I don't really want to spend time or money on them. I'm pretty sure they've been set for a while. But not much more than an annoyance on the taguchi loss function curve. The evap just makes it a little hard to crank after a fill up.

Oh, BTW, went thru the related fuses and relays and hit them all with contact cleaner and reseated them.

I am interested that you say the vvt solenoids don't necessarily trip codes, because other threads I read said only replace them if the codes for them were set? If they don't always trip codes should I just replace them?

Depending on the codes you actually have, yes they could cause the problem you are having.

Until you get them there really is no use talking about it.

There are a lot of O2 sensor codes and EVAP codes. And a lot of codes that may be misconstrued as one of those.

Donbrew is right - the solenoids COULD cause the problem you are having - but there is no direct evidence AT ALL, that the solenoids are at fault. And you are right in that the solenoids don't necessarily trip codes (due to drive cycles I suspect).

He is also right about it being rather futile discussing the issue until you get the actual codes downloaded and posted.

There are so many other codes and defective parts that can cause the hard shifting and T/C issues so suspecting the solenoids without any evidence to back it up is likely to result in you just throwing your money away.

Thanks for all of your responses and help so far. Codes

P0449
P0030
P0036
P0053
P0054
P0102
P0443

All of those codes together lead me to an electrical problem, most likely a fuse or 2 and/or a wire burned or frayed.

check under hood fuse #33 (controls all of the codes).

http://www.obd-codes.com/p0449

http://www.obd-codes.com/p0443

http://www.obd-codes.com/p0030

http://www.obd-codes.com/p0036

P0053 - OBD-II Trouble Code | BestRide.com

P0054 - OBD-II Trouble Code | BestRide.com

http://www.obd-codes.com/p0102

All these have a common denominator, electrical!
Loose or burnt fuses, loose or burnt ground wires!!
Loose connection, bent pins in the connections

If you find #33 is blown, find out why before you replace it. Probably a wire laying on the exhaust or rubbing on the engine.

Thanks don. I'll check both as soon as I get it back from my wife. She found a nursing job with one of her former employers where they promised she wouldn't have to do any lifting and she needs it to get back and forth to work since her 16 year old Benz is down, again. But she won't get rid of it because it was her late husband's.

If anybody wants to complain about GM, try working on and buying parts for a 16 year old Benz!

That's during the Chrysler debacle!:lol:

Yeah, she gets upset when I call it a Mercedes Dodge. :)

But I should have more respect for the Mopar name. My brothers stock 340 duster could dust my trans am. Mine had 140 on the speedometer and I was doing it when he went around me.

But, at the end of the day, mine was a trans am!

I can't say the current Mercedes is in any better shape than it was though, a friend bought a c class a few years ago and it's been in the shop for three years because they installed the wrong radio in it. Messed up every system in it. But she's content driving all the loaners they've given her because it's keeping the miles off of hers

Don, you are a genius! Fuse 33 is toast!

Thanks to everyone else too. Now I just have to go on a treasure hunt and find the likely assignable cause.

Did the new fuse poop out too?

Didn't try blue. Looking for the reason first