Turbos Cut Out
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Hi Felix,
No, I haven't. I've had the car checked for a list of possible cuprits which Kevin helped me with (e.g. wiring, spark plugs, N75 frequency valve, fuel pump, etc.). I've installed a boost gauge and have been monitoring boost with pump and race fuel... Boost is around 16psi with normal fuel... and I've also been having great fun checking the boost with race fuel, which hits 17-18psi
Any suggestions?
Thanks
No, I haven't. I've had the car checked for a list of possible cuprits which Kevin helped me with (e.g. wiring, spark plugs, N75 frequency valve, fuel pump, etc.). I've installed a boost gauge and have been monitoring boost with pump and race fuel... Boost is around 16psi with normal fuel... and I've also been having great fun checking the boost with race fuel, which hits 17-18psi
Any suggestions?
Thanks
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I get the same problem when my MAF gets dirty. I just take out the two screws holding it in place, pull it out and spray some carburator cleaner. Then I get the remaining dirt with a paper towel.
If you have a K&N type air filter,this will happen every couple of months. Do not use the K&N oil on the filter.
BTW - I do this around every 2 months and I have never damaged the MAF sensor with carburator cleaner.
If that doesnt help, shoot me an email and ill help you out.
If you have a K&N type air filter,this will happen every couple of months. Do not use the K&N oil on the filter.
BTW - I do this around every 2 months and I have never damaged the MAF sensor with carburator cleaner.
If that doesnt help, shoot me an email and ill help you out.
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Originally Posted by expressmechanic
If you have a K&N type air filter,this will happen every couple of months.
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Originally Posted by Ziad
Hi Felix,
No, I haven't. I've had the car checked for a list of possible cuprits which Kevin helped me with (e.g. wiring, spark plugs, N75 frequency valve, fuel pump, etc.). I've installed a boost gauge and have been monitoring boost with pump and race fuel... Boost is around 16psi with normal fuel... and I've also been having great fun checking the boost with race fuel, which hits 17-18psi
Any suggestions?
Thanks
No, I haven't. I've had the car checked for a list of possible cuprits which Kevin helped me with (e.g. wiring, spark plugs, N75 frequency valve, fuel pump, etc.). I've installed a boost gauge and have been monitoring boost with pump and race fuel... Boost is around 16psi with normal fuel... and I've also been having great fun checking the boost with race fuel, which hits 17-18psi
Any suggestions?
Thanks
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This sounds like the MAF limit of the Motronic ecu is being reached prematurely. As far as I know, the Motronic ecu monitors the voltage of the MAF circuit and if a predetermined limit is reached it cuts the ignition/boost to bring the MAF voltage back into line. This always happens at peak torque which roughly coincides with the peak efficiency of the turbo/engine combination. If it is this problem there is no immediate and simple fix as the code is buried in the ecu chip. If you have a standard car I do not know why you are reaching the MAF limit unless there is a fault somewhere.
I think the way most tuners get around this issue is to fit a resistor in the MAF supply to reduce the voltage seen by the ecu for any given demand and then rescale the fuel table accordingly to compensate for the change. I have always seen this as a bit of a bodge, but there are other solutions which get around the chip code location problem, like fitting a larger AFM body which flows more air through for any given velocity. We don't work with the Motronic ecu so unfortunately I cannot help any further.
I think the way most tuners get around this issue is to fit a resistor in the MAF supply to reduce the voltage seen by the ecu for any given demand and then rescale the fuel table accordingly to compensate for the change. I have always seen this as a bit of a bodge, but there are other solutions which get around the chip code location problem, like fitting a larger AFM body which flows more air through for any given velocity. We don't work with the Motronic ecu so unfortunately I cannot help any further.
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Originally Posted by NineMeister
there are other solutions which get around the chip code location problem, like fitting a larger AFM body which flows more air through for any given velocity. We don't work with the Motronic ecu so unfortunately I cannot help any further.
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Originally Posted by Acropora
Where does one come by this larger AFM body? My understanding is that the MAF is the bottleneck in higher power engines and I'd be interested if there's a larger one available somewhere.
Does anyone know how Todd or RS get around the stock ecu's MAF voltage limit or do they just frigg it with a resistor (I'm sorry - please read this as "use a voltage clamp") like everyone else?
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Hello Mark
I had a lot of components checked. In the end, I don't think I changed anything cos nothing needed changing. The problem just never came back...
I had a lot of components checked. In the end, I don't think I changed anything cos nothing needed changing. The problem just never came back...