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Discussion Starter · #1 ·
My check engine light keeps coming on despite checking the gas cap and replacing the "purge valve". I scanned it and came up with
P0170 Bank 1 Fuel trim Malf
P0173 Bank 3 Fuel trim Malf

Also is there a trick to the fuel cap? It seems pretty straight forward.

Anybody have any ideas on where to start, it is a 2000 G500 45,000 miles

Thanks in advance
Bill
 

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As a confirmed dieselhead, I'll defer to others with more knowledge. That being said, the error codes sound more like the ECU feels that it has gone to the limit on how much it can adjust the fuel quanity. Most likely a fuel pressure or fuel filter problem. Especially so since it is happening on both sides. The filter is likely easy to swap and cheap. If it hasn't been changed recently I do that first.
 

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Fuel Filter

AlanMcR - 2/7/2005 4:38 PM

As a confirmed dieselhead, I'll defer to others with more knowledge. That being said, the error codes sound more like the ECU feels that it has gone to the limit on how much it can adjust the fuel quanity. Most likely a fuel pressure or fuel filter problem. Especially so since it is happening on both sides. The filter is likely easy to swap and cheap.
Cheap it's not. It now has the pressure regulator and retun line built into it. It's €100,34 in Europe right now.
 

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Mass Air Flow Sensor

discap - 2/7/2005 3:37 PM

My check engine light keeps coming on despite checking the gas cap and replacing the "purge valve". I scanned it and came up with
P0170 Bank 1 Fuel trim Malf
P0173 Bank 3 Fuel trim Malf

Also is there a trick to the fuel cap? It seems pretty straight forward.

Anybody have any ideas on where to start, it is a 2000 G500 45,000 miles

Thanks in advance
Bill
Give Europa a call and ask Jason what they might mean; but my guess is that it's the MAF, which is a fairly common problem on the M112 and M113 engines. It can be had on the discount parts market waaayyyyy cheaper than from a dealer or Europa; and I understand it's pretty simple to swap out.

When you refer to the "purge valve", are you referring to the one located under the hood on the right side near the rear of the engine?
 

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at about 37k miles my fuel filter died and took the pump with it... at least that's what the shop said and i makes some sense that a clogged filter could kill a pump... though my honda survived which quite a bit of abuse (clogged filter). Shouldn't have to be changed for like 60k miles, but oh well. i want to say i felt it hesitate a few times on the highway before that when using cruise control, but who knows. I never got a warning code for that though, it just died.

I get P0140 "small evap emission control leak" about every 1k-3k miles (about once every month or two). I heard 3 things can typically cuase it, gas cap, purge valve and i don't know the 3rd. I've changed none of them though i have a purge valve ready... i'm lazy just because i hate to change something non-critical that really isn't malfunctioning but evey once in a while.


Hey, while were on this subject, my fuel gage stops moving just after i hit the 4 gallon mark when the fuel light comes on. Doesn't really bug me because it does a good job tellin me when i have 4 gallons left, and i know my mileage, but any quick service i can do?... or ask a shop to do?

THis happened with my fuel pump/filter death. Any reason i can blame the shop who did the fix?, or the fuel level meter just took some damage in the fall?

Thanks ahead of time.
 

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P0140 - 3rd Cause

ewalberg - 2/7/2005 5:07 PM



I get P0140 "small evap emission control leak" about every 1k-3k miles (about once every month or two). I heard 3 things can typically cuase it, gas cap, purge valve and i don't know the 3rd.
The 3rd cause can be the valve (don't know the name) that's located above the liner in the RR wheel well. It's way down the list in probability. 1st is the vlve up under the hood and the right side near the rea of the engine.
 

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Discussion Starter · #7 ·
Thanks for the tips. I have a call in to Europa and am waiting for a call back. Is there a list of Error codes and meaning anywhere. I understand that manuals are not available for this engine. What is a guy to do?

Where is the fuel filter?

Yes the "purge valve" I swapped is the little guy on the passenger side. When I searched the archives it was often pointed out as a potential problem, so I swapped it out.

Where did you guys get the info that you are offering?

Thanks
Bill
 

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discap - 2/7/2005 5:17 PM

Thanks for the tips. I have a call in to Europa and am waiting for a call back. Is there a list of Error codes and meaning anywhere. I understand that manuals are not available for this engine. What is a guy to do?

Where is the fuel filter?

Yes the "purge valve" I swapped is the little guy on the passenger side. When I searched the archives it was often pointed out as a potential problem, so I swapped it out.

Where did you guys get the info that you are offering?

Thanks
Bill
Don't hold your breath on a call back.

As for the P0170 & P0173 codes, there's another fourm with a lot of professional technical available; and those codes are almost always referred to the MAF to fix.
 

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Discussion Starter · #9 ·
Where is the other forum?

What is the MAF?

Where is the Fuel Filter?

Come to think of it I have called Europa a couple of times before and am still waiting on the call back. Does asking for Jason work better than just calling service?

Thanks
Bill
 

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My check engine light/check gas cap message turned out to be the RR valve - part# 000 476 67 32 for $71.28

Harald
 

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Second try at a better picture of "does this help"
 

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Discussion Starter · #12 ·
Thanks for all the input.

JR I cannot read your picture. Where did it come from? I even printed it out and used a 4X loupe.

I just reread my original post and I don't know if it makes a difference or not but P0173 should read Bank 2 not Bank 3 (typo)

Hey Europa is calling back got to go
 

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JRBrown, try cropping the right side of the picture (that's just blank space) and then rotating 90 degrees. Posting picture with the long way vertically will get you more detail. That's what i did when i posted the diff locker wiring diagram.
 

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ewalberg - 2/7/2005 2:07 PM
Hey, while were on this subject, my fuel gage stops moving just after i hit the 4 gallon mark when the fuel light comes on. Doesn't really bug me because it does a good job tellin me when i have 4 gallons left, and i know my mileage, but any quick service i can do?... or ask a shop to do?

THis happened with my fuel pump/filter death. Any reason i can blame the shop who did the fix?, or the fuel level meter just took some damage in the fall?

Thanks ahead of time.
Mine also stops when the light goes on. I assumed that was a "feature" rather then a bug. I suppose that there could be crud on the slide wires. That would be pretty likely if the previous owner always filled up right when the light came on.
 

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I Repeat

discap - 2/7/2005 6:18 PM

Thanks for all the input.

JR I cannot read your picture. Where did it come from? I even printed it out and used a 4X loupe.

I just reread my original post and I don't know if it makes a difference or not but P0173 should read Bank 2 not Bank 3 (typo)

Hey Europa is calling back got to go
P0170 & P0173 indicate a bad Mass Air Flow Sensor. Common problem in the M112 & M113 engines. It's located in the air intake pipe at the top back of the engine.

I haven't done the job myself, but it's supposedly a pretty simple screwdriver job to replace.

What did Europa say?
 

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it actually read all the way to empty before the filter and pump got replaced... that's what makes me wonder if there's any way the shop could have accidentally caused the problem.
 

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EW....

Thanks for the hint on posting a pic. Sure wish we could post ADOBE....

How does the new pic look? I reposted inot the original posting.
 

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Fuel Filter Location

discap - 2/7/2005 5:45 PM



Where is the Fuel Filter?
The fuel filter is located next to the longitudinal frame member on the driver's side. It is an aluminum can with four (4) hoses connected to it - two to the front and two to the rear. It is just above a horizontal cross member and right next to the differential lock fluid intensifiers just about directly under the driver's seat.
 

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ewalberg - 2/7/2005 4:07 PM

at about 37k miles my fuel filter died and took the pump with it... at least that's what the shop said and i makes some sense that a clogged filter could kill a pump... though my honda survived which quite a bit of abuse (clogged filter). Shouldn't have to be changed for like 60k miles, but oh well. i want to say i felt it hesitate a few times on the highway before that when using cruise control, but who knows. I never got a warning code for that though, it just died.

I get P0140 "small evap emission control leak" about every 1k-3k miles (about once every month or two). I heard 3 things can typically cuase it, gas cap, purge valve and i don't know the 3rd. I've changed none of them though i have a purge valve ready... i'm lazy just because i hate to change something non-critical that really isn't malfunctioning but evey once in a while.


Hey, while were on this subject, my fuel gage stops moving just after i hit the 4 gallon mark when the fuel light comes on. Doesn't really bug me because it does a good job tellin me when i have 4 gallons left, and i know my mileage, but any quick service i can do?... or ask a shop to do?

THis happened with my fuel pump/filter death. Any reason i can blame the shop who did the fix?, or the fuel level meter just took some damage in the fall?

Thanks ahead of time.
In the 02+ the fuel pump and the level gauge are integrated - or so I've been told. It could be the shop's fault.
 
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