Hello,
Today i was driving on the high way and all of the sudden the "Restricted Performance" lights up on my odometer as well as the check engine light .
The car now feels a bit slugish. Why is this happening?

Any opinions are greatly appreciated.
-Alex

 

What are the OBD codes?

 

I got one of those this last week! Code was a P0174...lean bank 1 IIRC. The RP light was on for maybe 5 seconds. The CEL stayed on. CEL did go away on its own after a few days, but I did a MAF sensor cleaning nonetheless (cuz the JTIS seemed to think it may be sensor related), hard reset the car, and it hasn't returned. <knock on wood>

 

Here are the codes.

P0171 x2
P0128
P1111

 

P0171 = System too lean(Bank1)
P0128 = Coolant thermostat(Coolant temp below thermostat regulating temperature)
P1111 = System Pass

 

See below the possible causes (P0171) but the simple question is when is the last time you cleaned your MAF sensor? (I live in a dusty climate, use a K&N Air fliter and always clean my MAF after oiling and every 4 months)

Engine misfire:

• Air intake leak between MAF Sensor and cylinder head

• Fuel filter / system restriction

• Fuel injector restriction

• IP Sensor fault (low fuel pressure)

• Low fuel pump output

• HO2 Sensor(s) (1/1, 1/2) harness wiring condition fault

• EFT Sensor fault (low fuel temperature)

• MAF Sensor fault (low intake air flow)

• Exhaust leak (before catalyst)

• ECM receiving incorrect signal from one or more of the following components:ECT Sensor, MAF Sensor, IAT Sensor, IP Sensor, EFT Sensor, TP Sensor

 

sounds very similar to mine (w/o the coolant temp low code)

MAF sensor, clean and clear (the code that is) and report back ASAP.

BTW, how can you have 0171 x2? If you have both banks lean, look for air leaks inbetween the air box and TB. But if only one bank code, i'm still leaning towards the MAF sensor.

The sluggishness was never a symptom of mine however. You could very well have a vacuum leak.