Hello guys i have a 2004 mb C230 and this saturday i was driving around the city when the check engine light came on i didnt notice anything abnormal so i kept driving, it has been 5 days today and i finally had the time to take it to auto zone to check for the codes "its free there" so anyways the codes i got are P0172 and P0301 the only problem i have is that they didnt have the book that tells what the code means. any suggestions ? also my car has 52450 miles on it.

thanks for the replies

 

i forgot to say that today i noticed when i start the engine and its on park the rpm go from 1000 to 1500 slowly then drop back to around 700 then after let say 30 seconds it goes back to 1000 to 1500. but when i turn the a/c it runs at 700 steady is this normal ? i never noticed but again never had any problems with this car before.

 

i dont have a code reader but the simptoms sound like a air flow metter or iddle sensor

 

yup that could be i just took apart the air filter and it looks like crap i replaced it a while ago, im buying a new one at the MB dealer lets hope this fixes the problem. i deleted the codes and the check engine hasnt come back on so lets see

 

what i did to my old irflow metter i cllean it with contac cleaner and i did this with the battery disconected and everithing went fine