Don't update this thread much these days as I don't do much to the car spend all my time tatting with the TT. The car has been uber reliable but did have an issue with it the other week after I noticed wet patches on the drive. Turned out to be diesel leaking from the extra diesel pump I fitted to help keep the fuel pressure up.
On the CAPA with the CP3 pump there is an in tank pump delivering fuel to the injection pump. On the CCWA the intank pump delivers fuel to a 5 bar electric pump that then passes the fuel onto the injection pump.
The extra pump I fitted was a generic Ebay item thats been on there a few years and now seems to be leaking from the crimped joint on the end of the body. So initially I removed the extra pump to see how the car went. Drives fine 99% of the time but found it very occasionally went into limp mode with low fuel pressure, not the best when you are half way past somebody overtaking them.
Doing some logging on VCDS. The actual pressure cannot follow the specified closely at high RPM and large injection amounts. I actually had it go into limp mode when I was doing a logging run. It seems if actual lags specified by 200 bar it will go into limp mode.
Normal injection pressure on a CAPA is 1600 Bar. Mine is mapped to 1800 Bar. This log without the extra pump.
Decided to buy a secondhand pump off a 2.0 TDI B8 with the CP4 pump, the same pump as used on CCWA engines. Cheap enough at £30 and it fits perfectly as it's designed to fit where the filter is.
8K0906095B

Done some testing tonight and normal service is resumed
. No limp mode even when running car to the red line through the gears
.
Actual pressure doesn't always meet specified but it's a lot closer so won't go into limp mode now.
On the CAPA with the CP3 pump there is an in tank pump delivering fuel to the injection pump. On the CCWA the intank pump delivers fuel to a 5 bar electric pump that then passes the fuel onto the injection pump.
The extra pump I fitted was a generic Ebay item thats been on there a few years and now seems to be leaking from the crimped joint on the end of the body. So initially I removed the extra pump to see how the car went. Drives fine 99% of the time but found it very occasionally went into limp mode with low fuel pressure, not the best when you are half way past somebody overtaking them.
Doing some logging on VCDS. The actual pressure cannot follow the specified closely at high RPM and large injection amounts. I actually had it go into limp mode when I was doing a logging run. It seems if actual lags specified by 200 bar it will go into limp mode.
Normal injection pressure on a CAPA is 1600 Bar. Mine is mapped to 1800 Bar. This log without the extra pump.
Decided to buy a secondhand pump off a 2.0 TDI B8 with the CP4 pump, the same pump as used on CCWA engines. Cheap enough at £30 and it fits perfectly as it's designed to fit where the filter is.
8K0906095B

Done some testing tonight and normal service is resumed
Actual pressure doesn't always meet specified but it's a lot closer so won't go into limp mode now.
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