GTI-R rev limiter after idling for extended period

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CoZZm0
 

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GTI-R rev limiter after idling for extended period

Post by CoZZm0 »

I read this in a thread a few weeks back and Matt mentioned he wasn't able to figure out where in the code this occurred for the Silvia. After allowing the car to idle for a few minutes a very low rev limiter of ~2krpm is imposed no matter how much throttle is applied. Switching the car off and back on restores function.

I saw a similar issue raised on the GTI-R forums the other day and unplugging the CAT TEMP SENSOR fixed the issue that the guy was having (the cat temp light was also lit on the dash, hence the reason he decided to unplug it, depsite the car being cold).

I was not aware that the cat temp sensor was in any way connected to the ECU and after trawling the workshop manuals for the GTI-R i couldn't even find mention of it. I don't own a GTI-R, but i'm wondering if the Silvias may have a similar cat temp sensor which could somehow, even perhaps by a signal sent from the cluster through another sensor input that will flag the ECU to lower the rev limit if the sensor is not connected, faulty, or the wiring is otherwise damaged.

Just a thought, probably not related but as it was quite a mystery (and i was sure it wouldn't have any effect on the issue) when it fixed it was rather surprised.
Fusion Ed
 

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Re: GTI-R rev limiter after idling for extended period

Post by Fusion Ed »

Make sure the base image matches that of the one on the ECU. I've seen this several times. (I.e. do not mix EU with JDM base images)
CoZZm0
 

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Re: GTI-R rev limiter after idling for extended period

Post by CoZZm0 »

The car is running a factory ECU.
PL
 

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Re: GTI-R rev limiter after idling for extended period

Post by PL »

I've seen this on the S14 SR20DET 69F00 ECU. Swapped to 74F00 image and it fixes it. I'll investigate the wiring...

Thanks
PL
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