Hello,
My check engine light comes on if I abruptly brake. Then it goes away after sometime (4-5 days). Any idea what could be wrong. I am planning to buy a code reader, any suggestions which one should I buy?

Thanks a bunch.

 

Your typcial auto parts store should carry an OBD II scanner. These work on 1996 models and later. I used my scanner on my 02 E320. Works great.

Good luck

 

I bought INNOVA reader and scanned the car (99 ML320). It gave read bunch of codes. Here are they:

P0100 - Mass or Volume airflow circuit
P0170 - Fuel Trim (Bank 1)
P0173 - Fuel Trim (Bank 2)
P0130 - O2 Circuit (Bank 1 Sensor 1)
10135 - O2 Heater Circuit (Bank 1 Sensor 1)

I just changes the plugs and fuel filter. Why would trim codes show up. Should I talk to dealer for this?

I want to know what can I fix myself. I am an engineer and have done some work on small motors.

If there are any procedures available please point me to them.

Thank you much.
Pradeep

 

those are MAF sensor codes so you might need a new MAF insert from germanstar maybe the MAF is causing your 02 sensors to throw codes. How is your truck running?

 

Hello,

Truck is running fine with a bit of power loss periodically. I an just concernt hat it might cause damage to other parts in the system.

I asked the local dealership to change it. They are charging $675 to replace it.

I have recently changed spark plugs and fuel filter.

thanks
Pradeep

 

MAF is sub $200 and takes 5 min to replace.

 

Check your vaccum lines going to the intake.

 

Thanks for your help guys. I cleaned MAF and truck is running great. But the light came back on. with P0170 and 173. These codes are telling me that my fuel trims are malfunctioning.

Are these easy to fix?

thanks
Pradeepp

 

Sometimes cleaning the MAF helps but usually the codes come back so its best to change the MAF insert which can be obtained from Germanstar

 

Hello,

I finally chnaged the MAF sensor and the fuel trim code are still there. I am guessing that it is some leak somewhere. Is my understanding right?

thanks
Pradeepp

 

I finally chnaged the MAF sensor got it from autohausaz for 173. Installed it and drove about 60 miles and CE light turned off. After 5-6 day of driving CE light came back on. I drove it another day and accelerated/floored the car while ideling for 5 6 secs cos I was mad. Then I turned it off and called it a day. In the morning CE light did not come on. But now I feel a bit loss of power.

Can someone please suggest what can I do to improve the feel of acceleration.