Mass air flow sensor or CPS will not start when engine is warm.
10-29-2010, 02:56 AM
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Mercedes ML430
Mass air flow sensor or CPS will not start when engine is warm.
I have a 2001 Mercedes ML 430 that has a problem where it will not start when the engine is warm. Is this a mass air flow sensor problem or the CPS? Also, would either of these make the check engine light come on? I got a code PO 170 and PO 173. Thank you
10-29-2010, 07:40 PM
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
looks like
you have both issues.
cps usually no code but hot stall or warm fail issue
maf is p0170 p0173
both parts less than $200 total at www.autohausaz.com and about 30 minutes to replace.
don't erase the code or disconnect the battery just let the new maf adapt the ecu it will clear itself
cps usually no code but hot stall or warm fail issue
maf is p0170 p0173
both parts less than $200 total at www.autohausaz.com and about 30 minutes to replace.
don't erase the code or disconnect the battery just let the new maf adapt the ecu it will clear itself
10-30-2010, 12:44 AM
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I don't think that's how OBD II works..
Someone on the forum will correct me if I am wrong.
As for the original problem, if no codes are set, it is most likely CPS. MAF causes fault codes to be set.
The ML needs a new CPS & MAF between the 100k/120k mile range - doesn't hurt to replace both and live in peace with them for the next 75k-100k miles...
10-30-2010, 01:30 AM
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
You be wrong
and I will correct you.
MAF will adapt the ecu back into range
takes several drive cycles until it adapts clearing the code will not adapt it and clearing the code via a hhs or disconnecting the battery will not adapt it and when it does adapt a so called hard reset will only serve to clear the light and set all your i/m readiness functions to not ready.
So the maf adapts and you go to get a smog test and fail for I/M issues not related to the maf at all and no check engine light on either.
Just install it and drive it.
maf diy and cps diy on the diy section www.benzworld.org w210 forum
same for the m112 and the m113 engine in your car
MAF will adapt the ecu back into range
takes several drive cycles until it adapts clearing the code will not adapt it and clearing the code via a hhs or disconnecting the battery will not adapt it and when it does adapt a so called hard reset will only serve to clear the light and set all your i/m readiness functions to not ready.
So the maf adapts and you go to get a smog test and fail for I/M issues not related to the maf at all and no check engine light on either.
Just install it and drive it.
maf diy and cps diy on the diy section www.benzworld.org w210 forum
same for the m112 and the m113 engine in your car
Last edited by ohlord; 10-30-2010 at 01:33 AM.
10-30-2010, 01:35 AM
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Mercedes ML430
Do you happen to know if it will pass smog inspection with the check engine light on? Does the MAF affect smog controls?
Thanks again!
Lance
Thanks again!
Lance
10-30-2010, 02:02 AM
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
The maf affects fuel trim
Which affects fuel which sets emission codes when unable to keep within a certain percentage of ideal.
So as long as the condition exists you won't pass smog test even if you clear the code or disconnect the battery.
In california the last test they do is look at the light.
Replace the maf and let it adapt
either that or you will be asking me how to do the convoluted drive cycle procedures to get your I/M systems ready
So as long as the condition exists you won't pass smog test even if you clear the code or disconnect the battery.
In california the last test they do is look at the light.
Replace the maf and let it adapt
either that or you will be asking me how to do the convoluted drive cycle procedures to get your I/M systems ready
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11-03-2010, 06:59 PM
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I agree that the ECU will self adapt after a MAF change over time...
and I will correct you.
MAF will adapt the ecu back into range
takes several drive cycles until it adapts clearing the code will not adapt it and clearing the code via a hhs or disconnecting the battery will not adapt it and when it does adapt a so called hard reset will only serve to clear the light and set all your i/m readiness functions to not ready.
So the maf adapts and you go to get a smog test and fail for I/M issues not related to the maf at all and no check engine light on either.
Just install it and drive it.
maf diy and cps diy on the diy section www.benzworld.org w210 forum
same for the m112 and the m113 engine in your car
MAF will adapt the ecu back into range
takes several drive cycles until it adapts clearing the code will not adapt it and clearing the code via a hhs or disconnecting the battery will not adapt it and when it does adapt a so called hard reset will only serve to clear the light and set all your i/m readiness functions to not ready.
So the maf adapts and you go to get a smog test and fail for I/M issues not related to the maf at all and no check engine light on either.
Just install it and drive it.
maf diy and cps diy on the diy section www.benzworld.org w210 forum
same for the m112 and the m113 engine in your car
I doubl't if a SMOG station will clear you for smog if you have fuel injection related fault codes registered...
11-03-2010, 10:08 PM
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
tHE P0170
AND P0173 WILL CLEAR THEMSELVES.
oNCE AGAIN AFTER THE MAF IS REPLACED there is no need to erase anything it will adapt the ecu and the light will shut off. Doing it that way v.s. your way keeps the i/m monitors ready and allows a pass on the test if the cel is off.
When it is off for real instead of just erased there are no more issues.
oNCE AGAIN AFTER THE MAF IS REPLACED there is no need to erase anything it will adapt the ecu and the light will shut off. Doing it that way v.s. your way keeps the i/m monitors ready and allows a pass on the test if the cel is off.
When it is off for real instead of just erased there are no more issues.
