I took my car b/c it was not shifting. The dealer's rep informed me that it was the floor shifter which was stuck at one speed. Paid about $850 for that repair. They were also supposed to check the cause of "Check engine light" (CEL) which had been on several months; but the light came back on soon after I left the dealership (car battery was disconnected and re-connected, so it takes about 45 minutes driving for my 2001 E320 to re-diagnose itself and display malfunctions). Took it back to the dealer (rep said he would not charge me again to re-check), and I was told it was the mass air flow sensor, and dealer quoted $832 to replace. I asked for the part number and went home. Did find it online (Bosch which is identical to the OEM one) for around $225, brand new! I installed it myself today and drove for about an hour and the "check engine light" stayed on until I got home where I turned the car off, and then, I re-started it, and sure enough the CEL is now off/gone!! I'm taking it tomorrow for a smog check as required for California registartion renewal, I'm hoping it will now pass smog check!! I'm happy I saved over $600 for doing it myself! The E320 car runs better now too. I hope this info will be useful to someone. Sadek1

 

Well your right. The computer will do a self-diagnosis or "driveability check" on itself in about 15 to 45 minutes of driving depending on codes. I have replaced a few coils on my car, took it out for a short drive, and sure enough the check engine light will go away after a restart.

Good job on doing it yourself. Its good to save money!

Jeff

 

the drive cycle program if the code cleared and the battery was disconnected the I/M status are going to read not ready for at least 3 values,and they will not test you.
the purpose of completing an OBD II drive cycle is to force the vehicle to run its onboard diagnostics. Some form of a drive cycle needs to be performed after DTCs have been erased from the PCM’s memory or after the battery has been disconnected. Running through a vehicle’s complete drive cycle will “set” the readiness monitors so that future faults can be detected (and potentially to pass inspection). Drive cycles vary depending on the vehicle and the monitor that needs to be re-set. Whenever possible, follow the drive trace prescribed for the specific vehicle/monitor in question. Some vehicle-specific drive cycles can be found in the vehicle’s Owner’s Manual.

The following “universal” drive cycle can be used as a guide to assist with re-setting monitors when a vehicle specific drive cycle cannot be located. This generic OBDII drive cycle begins with a cold start (coolant temperature below 122 degrees F and the coolant and air temperature sensors within 11 degrees of one another). This condition can be achieved by allowing the vehicle to “sit” overnight, and then by beginning the drive cycle the next day. Most drive cycles will be difficult to follow exactly under normal driving conditions, so the driver should exercise caution, road safety, and courtesy to others.

* Start the engine. Idle the engine in drive for two and a half minutes with the A/C and rear defroster on.
* Turn the A/C and rear defrost off, and accelerate to 55 mph at half throttle.
* Hold at a steady speed of 55 mph for three minutes.
* Decelerate (coast down) to 20 mph without braking or depressing the clutch.
* Accelerate back to 55 to 60 mph at ¾ throttle.
* Hold at a steady speed of 55 to 60 mph for five minutes.
* Decelerate (coast down) to a stop without braking.
get the i/m read at autozone for free it will tell you if the o2 sensors are in a ready state,same with the cats,etc.if not you are wasting time going to the smog test till they are ready,they have nothing to do with the cleared light from the maf r/r.they are emissions related items.

"GOT CODES?"
p.s. next time save yourself a possible big repair bill,don't drive around a long time with a cel on,a bad maf changes the fuel curve and can result in frying your o2 sensors,sh*t runs down hill!And find a good indie shop,if your not going to do your own repairs,the dealer will kill your wallet.

 

I need to do this as well. Are there any DIY tips posted anywhere .... or can you tell me how to do this ?

 

not clear on what you need to do.......
post the job,we can tell you how to do it.
ohlord
"GOT CODES?"

 

my check engine light is on ... and from reading - it sounds like I need to change the mass air flow sensor. Just looking for alitlle help - instead of taking it to the delaer or another shop.

 

Congrats Rossi430! I did the same thing on my 00 E430. Feels good when you can save $$$!

 

and I was told it was the mass air flow sensor, and dealer quoted $832 to replace.

I would report the dealer to the BBB. I would also stop by and ask to see the dealer's general manager to ask him why he was trying to steal your money. That is an outrageous overcharged for labor/parts. I want to see the dealer make money however, that is theft by deception. The maf cost them 200 dollars and 5 mins labor to replace.

 

if you think that your maf is malfunctioning, try cleaning it with maf cleaner or electronics cleaner. worked like a charm for me approximately 9 months ago. it's really easy to do. take the maf out of the car. you'll see two torx screws. take those out and seperate the element from the maf housing. spray the element liberally. let dry for 30 minutes put back together and install. if that doesn't work then you order one for $225. imho i would try to clean it first, probably get another 10000 miles out of it, you will eventually have to replace it though......oh and it will take a while for your cel to go out like it says above.

 

use anything but the crc maf cleaner if you clean it,and don't touch any part of the inserts fine wires with anything but the spray.Inserts,which are the part that get contaminated or burned out or falls out of range in the thermistor,are only 129 bucks at www.germanstar.net Ron has them for most years and engines.
ohlord
"GOT CODES?"
as to the diy,go to benzworld.org w210 forum diy section,the cleaning and r/r are written up quite nicely,pics and all.

And get the code reader at harbor freight or get them read at pep boys or kraggens etc. and post the codes before you do the maf.May as well confirm what the codes are pointing to before doing it and finding out the dealer did not know sh*t..........which is often the case.