boisehomes

My car will sometimes idle up from 500 to 2000 over and over again! The AC compressor will make it stop when it is running but it still seems to idle a little high? Pulled the air mass sensor and cleaned it with a suluion specificaly for that but still the same problem? Also anyone know what the other sensor by the air mass is? I can get a Bosch sensor for $262.00 from Autozone. Will this fix my idle or waste my money?? Any advice would really help me. I am very close to trading this car towards a 2006 Suburu WRX STi for autocrossing if I cant fix it!!!!

Thanks,
Troy

patrick_y

Yes, the 2000 RPM is definitely too high. I'm not sure if it's the air sensor, this could be more difficult and odd problems.

What kind of fuels have you been using? Have you been keeping up with regular service? This could become a very expensive fix.

I haven't driven the Subaru WRX STi, however, I have driven the "regular" version. Absolutely sublime. I think the Subaru WRX STi would be a great car to own and have. Some say the Lancer EVO is a nice car, but I disagree.

Musikmann

Nice stable of vehicles there Troy! I am not a mechanic, so if I were in your situation, I'd have the E420 diagnosed by someone who is. The last time I had my E430 looked at (Check Engine Light) a dealer told me up-front that there was a $95 charge. I went ahead with it, and they found a faulty O2 sensor; they had the part so just had them replace it.

Going to a dealer is probably NOT going to be the least expensive solution to your problem, but IMO, you WILL get to the bottom of it.

Paranthetically, out of your 3 fine autos, I think I would fix the Benz and trade your BMW

boisehomes

I always run chevron supreme! All maintenance has been performed! It is very strange as though I was slowly reving it up to 2000 then back to 500? AC commpressor running prevents it! I have absolutely no clue what it is! The last thing I did to the car was a radiator about 2 weeks ago. It Started a few days after that. Anyone ever had this happen?
and I always perform the work myself! Codes said something like fuel trim bank 2 etc. etc.
Thanks,
Troy

jmcdoogie

I had a post on here a couple of weeks ago about those same trouble codes, and Fatchance and Staplegun on this Board clued me in that it means BAD MAF. I did some more research based on their recommendations and learned some things.
BTW, the local MB dealer wanted to charge me $95 to check the error codes - so I drove over to Schucks Auto Parts who did it for free. Subsequently at Harbor Freight Tools I bought a Code checker for $50 that I'm going to use for all the OBDII cars in my personal "fleet" from now on.
If cleaning it didn't work, it might be FUBAR. Kind of ridiculous that an electronic part like the MAF would be considered a "wear" item.