markinnaples

OK, car had an irratic idle and surging at constant speed, so I took the following steps:

1. Fixed the defective $12 hose; small improvement
2. Car ran better for a while then crapped the bed and went into "limp mode" one night
3. Sprayed MAF with CRC MAF cleaner; ran perfect for a while then right back to "limp mode"
4. Replaced the MAF with a new one; ran better for a while then now occasionally surges a little and the idle is not bad but is occasionally a little erratic again
5. Now what? New O2 sensors?

Thanks for all of the great info you all provide on here.

C230 Sport Coup

Seafoam's new Medical marijuana treatment mon!
Your car will go a little slower, and the exhaust smells a little....funny,
but you know it's working when
your car intermittently plays Bob Marley all by itself!
Don't worry, be happy.

OK seriously I don't have an answer.

Javvy

if I may.....limp modes is an indication that some thing is going on in the tranny that is throwing the car in limp mode to protect the tranny....have you checked the pilot bushing on the transmission. These bushings have a rubber gasket that is prone to leak and force the tranny fluid up the harness and when this happens the contacts kindof shorts and this throws the tranny in limp mode...have that bushing checked out ASAP ...it is a $12 part, after it happned to me once I have 2 extra with me one I carry with me in the car and other in stock in the garage........hope that is not the case with you......

javvy

Glyn M Ruck

Is this car storing any codes? Clean all breathers including EGR circuit & check the throttle body.

markinnaples

I am going to get and OBD II scanner this weekend and check out the codes, thanks.

C230 Sport Coup

Is your CEL on?
If not, and you are going into limp mode, you'll need STAR diag to
really get a handle on it. But OBD is a good starting point.

I only went into limp mode twice.
Once when I installed an aftermarket HID kit, when turning on it generated
a voltage spike that caused havoc, and one other time,
the whole car died, would run, but the dash was dead completely and headlights on constant.
Sat in the shop for a few days...and it fixed itself....he couldn't read the codes since the
CANBUS wasn't working and in the end, it just started working again, and never had the problem return.

markinnaples

Yes, the CEL is on.

SunnyRayToronto

I'm with Javvy,... check transmission pilot bushing adaptor (transmission plug),.... search.

Also, the irratic idle and surging at constant speed could be leaking cam magnet sensor dripping oil onto ecu plug and O2 sensor.

Most places like Autozone or pep boys will do simple obd2 scan for free.