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hey guys, i am suspecting a block posibly of my return line for my fuel and hence high pressure. i have nismo 555cc injectors and a stock FPR and a GTR pump in my R33 GTST. running power fc with 66.5% correction and 0.18ms lag correction. on idle my car is running at like 9 afr!!! you can just smell the fuel for days but then when she is driving it all seems to be fine, but still a little too rich for my liking...

is there a way of checking the fuel pressure short of buying a guage? or at least checking if the return line has a small blockage and hence increasing the pressure?

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well then i will buy a gauge....thats not the answer i was looking for...thats the easy option...

well theres a way to test the return line

try to blow down it

or to clean to blow compressed air down it,

well then i will buy a gauge....thats not the answer i was looking for...thats the easy option...

sorry but there isnt! unless you know someone with one, there is no other way to get a reading.

Blocked return line would normally cause a ramped effect with the AFR's since at idle the std earthing reduces the voltage at the pump to slow down flow - so it would get worse as it revs up.

ok so i have blown out the lines with an air gun. the send line seemed to be clear but a whole lotta gunk came out of the return line, may have been caught in the check valve. went to my mechanic to test the fuel pressur and on idle it sits at 2 bar (32psi) is this correct? when it goes on the dyno soon i'll check it right up to 7000rpm...

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