Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 02-20-2012, 04:32 PM
777funk's Avatar
Registered User
 
Join Date: Dec 2006
Posts: 1,031
Anyone revived a MAF by cleaning it?

I may have a bad MAF in the 94 E320. Just checked and I have a new harness. Not sure about the throttle body or OVP Relay.

But I notice that if I unplug the MAF it'll run great (well as great as limp mode can be). If I plug it back in, it stalls and is all but un-useable once the engine warms up and enters normal run temp mode.

I'm really thinking this equals bad MAF sensor.

I sprayed a good amount of the cleaner on the wire/sensor portion of the insert and no change.

Curious if there's anything else I can do or if anyone else has had any luck with this?


If it's not something I can revive somehow, is there a way to buy just the Bosch insert? Any idea on how well aftermarket would work or otherwise?
I'm sketchy on whether or not this is my problem so I'd hate to dump a ton of cash into it.

__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.

Last edited by 777funk; 02-20-2012 at 04:55 PM.
Reply With Quote
  #2  
Old 02-20-2012, 04:39 PM
TX76513's Avatar
Platinum Member
 
Join Date: Apr 2003
Location: Brandon, Mississippi
Posts: 5,209
I have on the BMW but not the Benz. Becareful of what cleaning soloution is used - some have suggested that simple green is to strong and leaves a residue. Electronic contact cleaner is recommended and using a cue-tip on the sensors.
__________________
BENZ THERE DONE THAThttp://www.peachparts.com/shopforum/...c/progress.gif
15 VW Passat TDI
00 E420
98 E300 DT
97 E420 Donor Car - NEED PARTS? PM ME!
97 S500
97 E300D
86 Holden Jackaroo Turbo D
86 300SDL
(o\|/o)
Reply With Quote
  #3  
Old 02-20-2012, 06:08 PM
Graham's Avatar
Registered User
 
Join Date: Nov 2004
Location: Ontario, Canada
Posts: 4,393
Quote:
Originally Posted by TX76513 View Post
I have on the BMW but not the Benz. Becareful of what cleaning soloution is used - some have suggested that simple green is to strong and leaves a residue. Electronic contact cleaner is recommended and using a cue-tip on the sensors.
I did clean the MAF on my W210 early on. It lasted for about 6 months. By that time new ones had come down in price so I replaced it. No further problems. The Chinese inserts are now so cheap, they are worth a try.

I tried all sorts of cleaners including SG, contact cleaner etc. What you need to clean, is the actual hot film or wire (not sure what a 94 used). Problem is that whatever reached the hot surface is now baked on. Solvents probably won't remove it. I never tried it, but something like oven cleaner is probably needed! I think I tried Q-tips, but also pulled something back and forth to try and abrade the dirt off.

My memory is bad, but whatever I did, it did extend the life. But now, I would just buy a replacement.
__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5
Reply With Quote
  #4  
Old 02-20-2012, 07:45 PM
olpos's Avatar
Registered User
 
Join Date: Sep 2003
Location: san diego.ca.
Posts: 323
After going crazy trying to fix my maf code on a 1996 C280 it turned out to be OVP relay.This fixed 2 codes for me.If that does not work buy a german maf,not a cheapee.Cheap ones run good,no codes on new cars but can rich or lean and you will not know till you go for smog.Then thinking you have a good maf other parts will be changed instead.Not worth the savings for a cheap maf.
Thanks
Rich
__________________
88 300E White, sold 9-04
88 190E Black 2.3 sold
90 300CE White, Grey sold 12-24-04
92 400E White,Grey Sold 5-06
90 300CE 91K Signal Red,Black Sold 2007
1989 300CE Smoke silver,Tan Sold 1-08
1993 300E 3.2 M104 motor
1991 300CE White,Grey
1994 E420 beautiful car,gone to new home
1994 E320 Smoke an Parchment.Beautiful car
Reply With Quote
  #5  
Old 02-20-2012, 10:39 PM
Registered User
 
Join Date: Aug 2003
Location: Phoenix
Posts: 3,726
Cleaning is not usually very effective on hot film because dirty is not really the problem. They just get worn out and tired. Hot wire often cleans up nicely. I'll say there is no insert available for a 94, and we'll see if someone can come up with a link to one. German Star has a nice summary of available inserts - Mercedes MAF Sensor

What are the fault codes telling you?
Reply With Quote
  #6  
Old 02-20-2012, 10:56 PM
777funk's Avatar
Registered User
 
Join Date: Dec 2006
Posts: 1,031
I checked the codes (after clearing them and making sure all sensors were connected and running for a bit).

Got a 4 and a 13, there was a 24 in there too but it didn't come back after it was cleared. Who knows how old that code was.

Definitely a MAF code in there though.
__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.
Reply With Quote
  #7  
Old 02-20-2012, 10:58 PM
compu_85's Avatar
Cruisin on Electric Ave.
 
Join Date: May 2008
Location: La Conner, WA
Posts: 5,234
Is it a hot film or hot wire MAF? If it's hot wire I think you have a better chance of success. Many auto parts stores have MAF cleaning spray.

-J
__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.
Reply With Quote
  #8  
Old 02-21-2012, 02:13 AM
Can't Know's Avatar
Registered Slacker
 
Join Date: Sep 2010
Location: Sunny CA
Posts: 733
Cleaning a maf works great...if the problem is that the maf is dirty. At least with benz that seems rarely to be the case.

Personally I'd replace it with an OE Bosch; the aftermarket ones are too unreliable, and finding a quality insert seems to be a challenge. Considering how long they last, and how critical they are to so much, the extra money for a quality part isn't that extreme. If you shop around there are affordable ones.

That said, however, unplugging a MAF sensor is a hit-or-miss test. When it's out of the loop, everything is set to defaults, so if there is something else causing the problem (say a different sensor, or even a vacuum leak) the default settings can mask that, took. However, with the MAF code showing up, that reinforces the idea.

Good luck.
Reply With Quote
  #9  
Old 02-21-2012, 02:03 PM
Registered User
 
Join Date: Aug 2003
Location: Phoenix
Posts: 3,726
Quote:
Originally Posted by 777funk View Post
I checked the codes (after clearing them and making sure all sensors were connected and running for a bit).

Got a 4 and a 13, there was a 24 in there too but it didn't come back after it was cleared. Who knows how old that code was.

Definitely a MAF code in there though.
Can we assume you're talking about codes on the DM? Have you checked the other pins? Why do you say you're getting an MAF code? Nothing but questions for now.
Reply With Quote
  #10  
Old 02-24-2012, 01:38 PM
777funk's Avatar
Registered User
 
Join Date: Dec 2006
Posts: 1,031
Quote:
Originally Posted by deanyel View Post
Can we assume you're talking about codes on the DM? Have you checked the other pins? Why do you say you're getting an MAF code? Nothing but questions for now.
That was with the Arthur Dalton push button code reader. I think pin 8. According to my list that was a MAF code.
__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.
Reply With Quote
  #11  
Old 02-24-2012, 07:09 PM
Registered User
 
Join Date: Aug 2003
Location: Phoenix
Posts: 3,726
Which pin it was is really important. Most people giving code numbers without a pin number are testing just the DM on the built in LED. I think you're right - on pin 8 it's an MAF code.
Reply With Quote
  #12  
Old 02-27-2012, 01:28 PM
777funk's Avatar
Registered User
 
Join Date: Dec 2006
Posts: 1,031
Pin 8.

To update the thread: The problem ended up being the MAF sensor. Changed it and I've got an idle again.

__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 05:54 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page