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I have upgraded my turbo/ecu/injectors/cooler/fuel pump on my R33 GTS25t but have kept the stock fuel reg. my car is not running properly on any more than half throttle, but fine with anything less than that. the fuel pump is very noisy (Bosch 040) and is the 3rd brand new pump I have used. I am convinced its not the pump or the pump install.

My question is, could the car be in need of an adjustable fuel reg with the level of mods? Could not having an adjustable fuel reg cause any problems and what might the symptoms be? I have had all these mods fitted with 400rwhp in sight but due to this problem I have not been able to drive the car for nearly 2mths and its getting very annoying. before the mods were fitted the stock fuel pump and fuel reg were in 100% working order. About a week after fitting the mods, the problems started. Can anyone offer any advice?

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Not sure, but I thought an adj. fuel reg was for too small an injector size?

What size injectors did you get?

Half throttle???? Not anything to do with your secocnd stage advance??

What ecu you got??

yeah half throttle or less, car runs fine doesnt miss or anything. pump is still noisy though. once you put your foot into it, as it comes up on boost, it feels like a big fuel surge and the car doesnt rev. almost feels like it hits a fuel cut.

I have no been on the same pump for about 6wks. Would a f*cked pump last that long? The weird thing is it drives fine off boost.

Pump is noisy when the car is hot, and even early in the morning when its cold.

Injectors are 740cc and ECU is PFC with a Z32 AFM.

Use the diagnosis abilities of the power FC. Select the sensors/inputs screen on the Commander and watch the readings when the problem occurs. Look for unusual changes in voltage etc.

:P cheers :O

check the fuel pressure, that will tell you if you have a fuel problem. Get a bodgy autometer gauge, tee it in line and tape it to the outside of your windscreen, then go for a drive and see if the pressure changes inline with vacuum/boost.

I had 350rwkw/24psi Stock fuel reg.

Its perfectly fine.

If your reg was faulty, it would blow fuel @ idle if you give it a good rev. Thats how we picked my dead reg.

Or you could pressure test. Either way for 400rwhp, no problem on the stock item

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