P0170 help!
Thread Starter
Junior Member
Joined: Nov 2010
Posts: 44
Likes: 1
s430
P0170 help!
I have a code reader and I get p0170 so I came on here and saw that I should start with the maf sensor so I tried cleaning it first and the cel went away for about a week but it came back so I replaced the maf with an oem unit and the code is still there and I went ahead and checked the vacuum lines and everything seems ok any help would be great!
MBWorld Fanatic!
Joined: Apr 2007
Posts: 6,171
Likes: 16
300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
Maf
codes related to fuel trim come in the dual codes of 0170 and 0173.
One code only could be triggered by the pre cat o2 on your passenger side engine bank,or a vac leak,or a dirty fuel filter.
I suspect that you erased the code after cleaning the maf and the condition never really went away all it did was erase from view for a week and return.
Make sure the maf is properly seated on both ends.
Reinspect any lines on the pass side engine bank.
You are at enough miles (if over 100K) to need o2 sensors
Replace fuel filter(it is due)
These are all things that need to be done anyway
and if you go to a shop they will do them at much greater cost to try and solve the issue.
autohausaz.com has the fuel filter
also replace your air filter (not K/N)
One code only could be triggered by the pre cat o2 on your passenger side engine bank,or a vac leak,or a dirty fuel filter.
I suspect that you erased the code after cleaning the maf and the condition never really went away all it did was erase from view for a week and return.
Make sure the maf is properly seated on both ends.
Reinspect any lines on the pass side engine bank.
You are at enough miles (if over 100K) to need o2 sensors
Replace fuel filter(it is due)
These are all things that need to be done anyway
and if you go to a shop they will do them at much greater cost to try and solve the issue.
autohausaz.com has the fuel filter
also replace your air filter (not K/N)
Junior Member
Joined: Dec 2007
Posts: 59
Likes: 0
From: Philly, PA
2001 s 430 84Kmiles black on black
Bump! Driving from work today and getting "very pretty" check engine light on. Stopped at two locations to inspect and found Pending codes P0170 & P0173 . Some issues that i have noticed within past 2-3 weeks:
- misreading fuel gauge time to time,
- little "jerking" (similar to cylinder misfire) once or twice
- fuel consumption went up slightly (or its the gas prices @ $4/ gallon ? )))
other times runs just great, accelerate fine and all
Recently i did oil change and changed air filter. after reading a lot of posts on this forum and other websites looks like i have a MAF Mass Air Flow sensor going bad. So i will try to clean it first with CRC Mass Air Flow sensor cleaner. Im going to do some photo or video DIY for 2001 S430 . If its not gonna help - i will order MAF from Autohausz ($143 plus shipping i guess, made by BOSCH) or BOSCH OEM on ebay (i think its $135 free shipping) and will change it to see if it will solve the issues.
As of right now, my tech reset the CEL (Check Engine Light) and checked & tightened my Fuel Cap. Codes went away. Lets see if they will come up again, and if so - im up for some photo&video DIY!!!
- misreading fuel gauge time to time,
- little "jerking" (similar to cylinder misfire) once or twice
- fuel consumption went up slightly (or its the gas prices @ $4/ gallon ? )))
other times runs just great, accelerate fine and all
Recently i did oil change and changed air filter. after reading a lot of posts on this forum and other websites looks like i have a MAF Mass Air Flow sensor going bad. So i will try to clean it first with CRC Mass Air Flow sensor cleaner. Im going to do some photo or video DIY for 2001 S430 . If its not gonna help - i will order MAF from Autohausz ($143 plus shipping i guess, made by BOSCH) or BOSCH OEM on ebay (i think its $135 free shipping) and will change it to see if it will solve the issues.
As of right now, my tech reset the CEL (Check Engine Light) and checked & tightened my Fuel Cap. Codes went away. Lets see if they will come up again, and if so - im up for some photo&video DIY!!!
Last edited by mobilusa; Mar 16, 2011 at 08:19 PM.
Junior Member
Joined: Dec 2007
Posts: 59
Likes: 0
From: Philly, PA
2001 s 430 84Kmiles black on black
Here we go! After driving for 20 miles the CEL is on again. I gues im proceeding to step 2 - cleaning my MAF sensor. Already got a CRC MAF Sensor cleaner at Advance Auto Parts for $7 and found very detailed image, illustrating HOW TO CLEAN MAF SENSOR. It's for 2000 CLK430 but has same engine and airintake setup as w220's.
MBWorld Fanatic!
Joined: Apr 2007
Posts: 6,171
Likes: 16
300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
Use crc
maf cleaner not electronic part cleaner.
GGet a security bit set and remove the insert from the maf,that is the best way to clean it. DIY for doing that on www.benzworld.org w210 diy section.
Although I would save the 7 bucks and put it towards the new autohausaz maf for surely a cleaning will only be a temporary solution if a rare solution at all.
When you get 0170 and 0173 the maf is usually done in range wise.
Not much of a tech if he thinks tightening the gas cap is going to do anything related to 0170 0173 fuel trim codes. Maf is intake related. Gas cap is emissions related gross leak codes. You don't have those codes so no amount of gas cap screwing is going to solve your problem. Get a new mechanic while you are waiting for the new maf,the guy is clueless
get your own code reader they are only about 60 bucks at harborfreight tools. That way you won't need to go near that incompetent anymore.
GGet a security bit set and remove the insert from the maf,that is the best way to clean it. DIY for doing that on www.benzworld.org w210 diy section.
Although I would save the 7 bucks and put it towards the new autohausaz maf for surely a cleaning will only be a temporary solution if a rare solution at all.
When you get 0170 and 0173 the maf is usually done in range wise.
Not much of a tech if he thinks tightening the gas cap is going to do anything related to 0170 0173 fuel trim codes. Maf is intake related. Gas cap is emissions related gross leak codes. You don't have those codes so no amount of gas cap screwing is going to solve your problem. Get a new mechanic while you are waiting for the new maf,the guy is clueless
get your own code reader they are only about 60 bucks at harborfreight tools. That way you won't need to go near that incompetent anymore.
Junior Member
Joined: Dec 2007
Posts: 59
Likes: 0
From: Philly, PA
2001 s 430 84Kmiles black on black
maf cleaner not electronic part cleaner.
GGet a security bit set and remove the insert from the maf,that is the best way to clean it. DIY for doing that on www.benzworld.org w210 diy section.
Although I would save the 7 bucks and put it towards the new autohausaz maf for surely a cleaning will only be a temporary solution if a rare solution at all.
When you get 0170 and 0173 the maf is usually done in range wise.
Not much of a tech if he thinks tightening the gas cap is going to do anything related to 0170 0173 fuel trim codes. Maf is intake related. Gas cap is emissions related gross leak codes. You don't have those codes so no amount of gas cap screwing is going to solve your problem. Get a new mechanic while you are waiting for the new maf,the guy is clueless
get your own code reader they are only about 60 bucks at harborfreight tools. That way you won't need to go near that incompetent anymore.
GGet a security bit set and remove the insert from the maf,that is the best way to clean it. DIY for doing that on www.benzworld.org w210 diy section.
Although I would save the 7 bucks and put it towards the new autohausaz maf for surely a cleaning will only be a temporary solution if a rare solution at all.
When you get 0170 and 0173 the maf is usually done in range wise.
Not much of a tech if he thinks tightening the gas cap is going to do anything related to 0170 0173 fuel trim codes. Maf is intake related. Gas cap is emissions related gross leak codes. You don't have those codes so no amount of gas cap screwing is going to solve your problem. Get a new mechanic while you are waiting for the new maf,the guy is clueless
get your own code reader they are only about 60 bucks at harborfreight tools. That way you won't need to go near that incompetent anymore.
Regarding the fuel cap - no joke i had almost the same issue with my BMW 740il in the past. the air was leaking inside of the tank due to old fuel cap and i had CEL light on (dont remember the codes). After replacing the fuel cap with new one problem went away.
Anyway, most of the small repairs/changes i do on my own and love it!!!
