Chip + Mass airflow sensor question
06-14-2009, 04:10 PM
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Chip + Mass airflow sensor question
Hi everybody,
I bought my C4 last summer with some modifications done to it. It has a FVD tuning kit including : 964 turbo (left side) exhaust, BMC air intake, lightweight flywheel, chip and mass airflow sensor from the 964 turbo (or 993, not sure).
However the chip and MAF aren't installed right now, and the previous owner of the car suggest that I don't use them. He said that if I put the chip, I have to replace the original MAF with the one that comes in the tuning kit because the mapping settings of the car is different (that's why the original MAF won't do it and I need to plug the upgraded one from the turbo 911).
On top of that, he told me that the MAF from the 911 turbo is very sensitive to humidity and rain, and that while driving under those conditions the car will start behaving horribly (it won't be smooth, it will hesitate during accelerations, struggle etc...), and then you have to buy an other MAF that costs a few hundreds...
Did some of you guys have such problems ? Is there some kind of maintenance that we can do so that the MAF stays clean ?
Is it impossible to just replace the original eprom with a 'racing' chip without changing the MAF ?
Thanks a lot for helping me,
have a nice day
I bought my C4 last summer with some modifications done to it. It has a FVD tuning kit including : 964 turbo (left side) exhaust, BMC air intake, lightweight flywheel, chip and mass airflow sensor from the 964 turbo (or 993, not sure).
However the chip and MAF aren't installed right now, and the previous owner of the car suggest that I don't use them. He said that if I put the chip, I have to replace the original MAF with the one that comes in the tuning kit because the mapping settings of the car is different (that's why the original MAF won't do it and I need to plug the upgraded one from the turbo 911).
On top of that, he told me that the MAF from the 911 turbo is very sensitive to humidity and rain, and that while driving under those conditions the car will start behaving horribly (it won't be smooth, it will hesitate during accelerations, struggle etc...), and then you have to buy an other MAF that costs a few hundreds...
Did some of you guys have such problems ? Is there some kind of maintenance that we can do so that the MAF stays clean ?
Is it impossible to just replace the original eprom with a 'racing' chip without changing the MAF ?
Thanks a lot for helping me,
have a nice day
06-14-2009, 04:27 PM
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I don't know how to help with your specific situation, but I would check out Steve Wong's offerings. He knows a ton about this, and might be able to help you with a custom offering.
http://911chips.com
http://911chips.com
06-14-2009, 05:15 PM
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Believe me, I am not an expert by any means, but there are so many different possible answers depending upon what you really have going with your modifications and potential modifications.
First the chip/MAF. The chip that is installed now, must have been reprogrammed already to account for the turbo and who knows what else, i.e Larger injectors, fuel pump, etc.
Also, I was a bit confused by what you wrote> Do you already have a MAF installed and are just thinking about swapping it out for a different one or do you currently have an AFM installed and want to change the AFM to a MAF? If the latter is the case, yes you will need another re-mapping. If you are changing one MAF for another, I don't know if you would need a re-mapping or not. Regardless, I have 993 MAF installed and have no problems and was a great improvement over the AFM, at least where I live in the high altitude environment of 9,000 feet.
First the chip/MAF. The chip that is installed now, must have been reprogrammed already to account for the turbo and who knows what else, i.e Larger injectors, fuel pump, etc.
Also, I was a bit confused by what you wrote> Do you already have a MAF installed and are just thinking about swapping it out for a different one or do you currently have an AFM installed and want to change the AFM to a MAF? If the latter is the case, yes you will need another re-mapping. If you are changing one MAF for another, I don't know if you would need a re-mapping or not. Regardless, I have 993 MAF installed and have no problems and was a great improvement over the AFM, at least where I live in the high altitude environment of 9,000 feet.
06-14-2009, 06:14 PM
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Ok, it sounds a little bit confusing, I know.
Let's say things this way.
The car has a kit (with the parts I mentioned in first post) with everything installed except the custom chip and MAF from 911 turbo (964 or 993).
Why ? Because when the previous owner drove the car with the custom chip + aftermarket maf installed, the car started behaving bad during humid/rainy weather, and decided to put the original chip and MAF back.
When I bought the car, he gave me the custom chip and MAF (that comes from the 911 turbo), and told me that I shouldn't use them or I will have problems with the car because of the MAF getting dirt due to bad weather. Or else, I can install them but only during summer when there's no rain.
So, I asked him if I can install only the custom chip and leave the original MAF. He told me that if I put the custom chip then I have to put the MAF also because of different mappings. And then I will have problems when it's rainy, the car will "bounce", it will be impossible to drive properly.
How it comes I've never heard people with 911 turbos complaining about their MAF failing quickly during bad weather ? Is there some maintenance I can do on the MAF so it stays clean ?
@psiegel :
the chip that is installed now is the original one and original MAF too.
what do you mean by "AFM", is it "aftermarket" ?
Let's say things this way.
The car has a kit (with the parts I mentioned in first post) with everything installed except the custom chip and MAF from 911 turbo (964 or 993).
Why ? Because when the previous owner drove the car with the custom chip + aftermarket maf installed, the car started behaving bad during humid/rainy weather, and decided to put the original chip and MAF back.
When I bought the car, he gave me the custom chip and MAF (that comes from the 911 turbo), and told me that I shouldn't use them or I will have problems with the car because of the MAF getting dirt due to bad weather. Or else, I can install them but only during summer when there's no rain.
So, I asked him if I can install only the custom chip and leave the original MAF. He told me that if I put the custom chip then I have to put the MAF also because of different mappings. And then I will have problems when it's rainy, the car will "bounce", it will be impossible to drive properly.
How it comes I've never heard people with 911 turbos complaining about their MAF failing quickly during bad weather ? Is there some maintenance I can do on the MAF so it stays clean ?
@psiegel :
the chip that is installed now is the original one and original MAF too.
what do you mean by "AFM", is it "aftermarket" ?
06-14-2009, 08:40 PM
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Without knowing what you have installed (MAF or AFM) and what MAF you have thats not installed its hard to know.
A few more thoughts and ideas;
1st you can clean a MAF with a spray type cleaner that is specific for the a MAF. You can get it at any auto parts store. It has to be for a MAF NOT a carb cleaner.
But, that doesn't sound like your problem if poor running happens only in the rain.
I would seek out and talk to who ever installed the turbo. If it was FVD themselves, they are good and should be able to help you sort through the issues. Regardless, speak with the installer. A few other questions in the meantime. Have you inspected the MAF, that is not installed? Does it have any part numbers? Is it a black cylinder? What is installed? Does it look like a silver box, with is generally what a AFM looks like.
Here is a photo of a 993 MAF installed in the C4. Does yours look anything like this?
A few more thoughts and ideas;
1st you can clean a MAF with a spray type cleaner that is specific for the a MAF. You can get it at any auto parts store. It has to be for a MAF NOT a carb cleaner.
But, that doesn't sound like your problem if poor running happens only in the rain.
I would seek out and talk to who ever installed the turbo. If it was FVD themselves, they are good and should be able to help you sort through the issues. Regardless, speak with the installer. A few other questions in the meantime. Have you inspected the MAF, that is not installed? Does it have any part numbers? Is it a black cylinder? What is installed? Does it look like a silver box, with is generally what a AFM looks like.
Here is a photo of a 993 MAF installed in the C4. Does yours look anything like this?
06-15-2009, 04:57 AM
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@crg53
Thanks I didn't know that. Then, what is the point of changing the AFM to a MAF ?
@psiegel
My car doesn't have any turbo, I didn't turbocharge it yet (it's something that I might do in the near future), the only 'turbo' spare part that I have is the MAF that comes from the 911 turbo (964 or 993). I have an AFM installed.
Thank you for the tips about cleaning a MAF.
I will check the MAF and look for part numbers, if you want I can take a picture of it.
Here's what I have :
http://shop.fvd.de/us/en/Porsche-0/9...964-89-94.html
Do you guys suggest that I change from AFM to MAF ? If yes, didn't you have troubles with MAF during some weather conditions ?
Thanks I didn't know that. Then, what is the point of changing the AFM to a MAF ?
@psiegel
My car doesn't have any turbo, I didn't turbocharge it yet (it's something that I might do in the near future), the only 'turbo' spare part that I have is the MAF that comes from the 911 turbo (964 or 993). I have an AFM installed.
Thank you for the tips about cleaning a MAF.
I will check the MAF and look for part numbers, if you want I can take a picture of it.
Here's what I have :
http://shop.fvd.de/us/en/Porsche-0/9...964-89-94.html
Do you guys suggest that I change from AFM to MAF ? If yes, didn't you have troubles with MAF during some weather conditions ?
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06-15-2009, 06:31 AM
#8
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The point of a MAF upgrade is to remove the big barn door flap in the AFM and provide more accurate metering. MY kit is a Vitesse Racing one and I'm driving it around at the moment in winter conditions with no undesirable effects.
Given the simplicity of the system it seems unlikely that the issues the previous owner had are related to the kit. FVD have a good reputation and it's unlikely that the kit would not function under all weather conditions. Normally there is a plug lead on the MAF kit designed to accept the standard 964 AFM plug and a couple of wires to provide 12v power.
It's a good kit in my opinion and I am very happy with mine. With a Cat bypass, secondary bypass and the MAF kit my car dynoed an average of just under 294 hp at the flywheel. Similar numbers are reported from other users with MAF kits of differing makes.
Neil
Given the simplicity of the system it seems unlikely that the issues the previous owner had are related to the kit. FVD have a good reputation and it's unlikely that the kit would not function under all weather conditions. Normally there is a plug lead on the MAF kit designed to accept the standard 964 AFM plug and a couple of wires to provide 12v power.
It's a good kit in my opinion and I am very happy with mine. With a Cat bypass, secondary bypass and the MAF kit my car dynoed an average of just under 294 hp at the flywheel. Similar numbers are reported from other users with MAF kits of differing makes.
Neil
06-15-2009, 09:24 AM
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Ok, this all makes sense now except for the cold weather problem. Call FVD maybe something is wrong with the temp sensor or the chip values. But I agree with Neil, its a nice simple upgrade that should not have problems.
Good luck and let us know how it turns out.
Good luck and let us know how it turns out.
06-15-2009, 10:01 AM
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@rotorheadcase
Thanks for those informations! I will try to install the FVD chip and MAF soon and see what I get.
@psiegel
I don't think there's anything wrong with the temp sensor or chip settings, because the previous owner told me that when the MAF would get dirty because of humidity (he says it's very sensitive to humidity), he would order a new one from FVD and the car would then work perfectly again until the new MAF gets dirty again.
I know it is a fact that bosch MAF fail easily on Audi's, VW's... and according to the previous owner of my car, on a Porsche it would fail even faster because if there's rain, it affects the engine area immediately (because the area is open) and the humidity gets the MAF dirty.
So I find it very interesting that you don't have those troubles, and I'm wondering what can I do in order to maintain the MAF in perfect condition, because I don't feel like buying a new one everytime it get's rainy.
Thanks for those informations! I will try to install the FVD chip and MAF soon and see what I get.
@psiegel
I don't think there's anything wrong with the temp sensor or chip settings, because the previous owner told me that when the MAF would get dirty because of humidity (he says it's very sensitive to humidity), he would order a new one from FVD and the car would then work perfectly again until the new MAF gets dirty again.
I know it is a fact that bosch MAF fail easily on Audi's, VW's... and according to the previous owner of my car, on a Porsche it would fail even faster because if there's rain, it affects the engine area immediately (because the area is open) and the humidity gets the MAF dirty.
So I find it very interesting that you don't have those troubles, and I'm wondering what can I do in order to maintain the MAF in perfect condition, because I don't feel like buying a new one everytime it get's rainy.
