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Discussion Starter #1 (Edited)
A funny thing happened to me. It´s the second time that I try to push the car, not extremely but fairly much, and the car loses power dramaticaly. It refuses to pull at high revs. When I stop the car and restart it, the problem disapears. Anyone experienced this before? Does anybody have any indications on what i might be? MAFS? Cylinder malfunction?

Thx
/Ice
 

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I am going through the exact same scenario as you are Ice, best that I can use to describe the condition is "limp mode". won't go above 3k RPM and fuel curves are basically that of a 92 Ford Aerostar minivan. ouich

Last night I decided to take a look at the MAF sensors on some advise from a great ///M resource locally and I didn't really notice anything "dirty" on them per sey, but decided to run through the motions of cleaning them in any case. All I can recommend is that you definately should give it a shot for what little time and resource goes into it. I took it out for a test after completion and if I were blindfolded I would have sworn I was NOT riding in the same car! :1:The power was quite a bit stronger, sooner and definately impressed my butt-dyno. The only problem was that on the way back, I believe my ailing clutch went
"I haven't had this much power in years...what's this??" as I experienced some slipping clutch in 3rd and 4th @ WOT, though from what I've read here, I should expect this from an almost 50k mile OEM clutch. I think the power being brought back highlited the need for a new clutch, on the upside, I don't believe I have a serious issue. I am still taking it to a very good dealer first thing on monday just to make sure (for my own comfort) and I'll be looking for a new clutch soon.

I can't say that it's the same problem you are experiencing, but for the little time and cost it takes to clean your MAF sensors, I would definately give it a shot. Good luck and happy ///Motoring! :cheers:

IceGBG said:
A funny thing happened to me. It´s the second time that I try to push the car, not extremely but fairly much, and the car loses power dramaticaly. It refuses to pull at high revs. When I stop the car and restart it, the problem disapears. Anyone experienced this before? Does anybody have any indications on what i might be? MAFS? Cylinder malfunction?

Thx
/Ice
 

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Discussion Starter #3
Thanks a bunch Sean

I also think the "limp home mode" is activated but I can´t figure out why.

I remember seeing a "do it yourself" MAF cleaning procedure here somewhere, but I can´t find it. Do you happen to have the link?

Many thanks
Ice
 

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Are you guys running K&N or OEM air filters?
 

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this is the one I used for mine and it worked great, hopefully it will have great results for you too! Click Here


Marcvip: I'm using new OEM (Mann) filters

:cheers:
IceGBG said:
Thanks a bunch Sean

I also think the "limp home mode" is activated but I can´t figure out why.

I remember seeing a "do it yourself" MAF cleaning procedure here somewhere, but I can´t find it. Do you happen to have the link?

Many thanks
Ice
 

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I have a very similar problem happening on my 2000 M5. It drives great when driven moderately, but when I go WOT, it seems to always set off the SES light and the car starts driving like it is misfiring. When I try to accelerate it makes a "blatt blatt" type of sound and you can feel that the car is running rough. The last time this happened, the codes that popped up were:

170 - Min secondary air flow
57 - mass air flow sensor
38 - O2 Heater ... Before ... (couldn't read mechanics notes??)
129 - internal index
196 - Misfire cylinder #1
0 - No description??
6 - (ABS) front right wheel speed sensor
7 - (ABS) front left wheel speed sensor

I hope it is just the MAF's that I have been reading about. It doesn't make any strange noises when I start it up cold. Pictures and description on the cleaning would be great.

Any of you technical experts care to comment on what the codes are telling me??cherrsagai
 

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If you follow the link that I posted for Mr. IceGBG, it is a very simple and completely picture directed guide to this very easy and much recommended project which takes less than 20 minutes to do and provides MUCH gratification.


Sean

Ducman69 said:
I have a very similar problem happening on my 2000 M5. It drives great when driven moderately, but when I go WOT, it seems to always set off the SES light and the car starts driving like it is misfiring. When I try to accelerate it makes a "blatt blatt" type of sound and you can feel that the car is running rough. The last time this happened, the codes that popped up were:

170 - Min secondary air flow
57 - mass air flow sensor
38 - O2 Heater ... Before ... (couldn't read mechanics notes??)
129 - internal index
196 - Misfire cylinder #1
0 - No description??
6 - (ABS) front right wheel speed sensor
7 - (ABS) front left wheel speed sensor

I hope it is just the MAF's that I have been reading about. It doesn't make any strange noises when I start it up cold. Pictures and description on the cleaning would be great.

Any of you technical experts care to comment on what the codes are telling me??cherrsagai
 

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Ducman69 said:
Pictures and description on the cleaning would be great.

Any of you technical experts care to comment on what the codes are telling me??cherrsagai

Member louv did a great write up about cleaning the mafs, it's linked a couple posts above.

I'd say your codes are consistant with a bad mafs, but i don't see it telling which side.
Mike
 

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Discussion Starter #10
Wow. what a differance. I clenaed the MAFS today. The lefte one (standing in front of the car) was really greasy. Afterwards the engine hesitated a bit at idle, but the car really is fast now at higher revs. It does not hesitate any longer.

Sean, thanks again for the tip.
 

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most welcome, the thanks go to louv for the fantastic writeup and pictures. If you are still experiencing some rough idle, you may want to try reseting the DME, that seemed to help mine out. :thumbsup:

IceGBG said:
Wow. what a differance. I clenaed the MAFS today. The lefte one (standing in front of the car) was really greasy. Afterwards the engine hesitated a bit at idle, but the car really is fast now at higher revs. It does not hesitate any longer.

Sean, thanks again for the tip.
 

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In all honesty, there is probably a fuse to pull for a few minutes that will reset the DME (if anyone has the Bentley manual and can assist?). I don't have the manuals myself so I can't tell you and I didn't know so I just pulled the negative terminal off the battery while I was cleaning MAF's and then hooked it back up. This way obviously will reset all your preset items on your NAV and computer so if that doesn't bother you, it's a quick and easy method. Does anyone have the easier/non-clearing method for the DME?

Hope this helps you out also, it did for me.

:cheers:

Sean
 

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I also developed hesitation on acceleration and I followed the procedure by Icegbg but used Formula 409 instead of simplegreen to get a better clean......works like a champ...

<TABLE cellSpacing=0 cellPadding=0 width=754 border=0><TBODY><TR><TD class=leftPane vAlign=top rowSpan=2><TABLE cellSpacing=0 cellPadding=2 width="95%" border=0><TBODY><TR><TD>
</TD></TR></TBODY></TABLE></TD><TD class=midPane vAlign=top>
</TD></TR><TR><TD class=midPane vAlign=top>
<TABLE cellSpacing=0 cellPadding=3 width=358 align=right border=0><TBODY><TR><TD vAlign=top>Formula 409 Orange Power Daily Kitchen Cleaner dissolves through kitchen messes on contact, even grease. With its natural orange scent and streak-free formula, it gives your kitchen a sparkling clean with the cool scent of freshly peeled oranges everyday!

</TD></TR></TBODY></TABLE></TD></TR></TBODY></TABLE>
 

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Discussion Starter #15
I used Ajax Al-clean, cleaned the MAFS with some q-tips and then rinsed them with some alcohol and it worked like a charm. The downside is that the idle is playing a little bit. I´m going to try to disconnect the neg.pole on the battery to see if it helps.
 

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Thanks to everyone on the great picture summary on the MAF cleaning procedure. I plan on doing this this weekend.
What a great place this is!!! :blabla: :blabla: :cheers:
 

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My beast if 5 years old with 30,000 miles, mostly local driving. I don't feel any performance problems, don't have any error codes or SES lights on right now. Is there any reason to clean the MAFs?
 
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