won't pull past 5000rpm

datdrift · #1 05-06-2006, 13:50

when under full load the motor won't pull past around 5 - 5.5 rpm.....i thought it might have been due to advanced timing, but now im thinking it may be down to lack of fuel getting to the engine

the fuel pump has been making occasional strange noises so i thought maybe its on its last legs?? anyone have any ideas, it has had this problem since i have had it when it was running a non-intercooled 8psi but it seems to be worse now im pushing more fuel thru.
thinking about it i havent changed the fuel filter since ive had it so maybe this is partly blocked??? i need to change the oil so i'll prob grab a fuel filter off nissan at the same time and see if it makes any difference

any ideas

adzs12 · #2 05-06-2006, 14:18

Check your injector plugs mate, i know pukka had a very similar problem and he found one of them was only making half contact

datdrift · #3 05-06-2006, 15:37

i'll have a look.....
just fitted a new fuel filter, and found the bit of fuel hose below it was well craked and perished, so put a new bit on, started her up and it started idleing at about 1500 - 1800rpm

when before its always idled at 8-900rpm

datdrift · #4 05-06-2006, 16:46

i took all the injector plugs off and gave then a little scrub with a bit of sand paper, re-gapped all the spark plugs and its still no better.......

+ its still ideling between 1500 - 2000rpm.....

northerner · #5 05-06-2006, 17:04

Is that Idle from cold as the Choke should be on. Also could be an Air leak from aroudn the Turbo etc

datdrift · #6 05-06-2006, 17:25

idle from warm and still doing it when hot, i don't think the choke works, cos its never idled higher than around 1000rpm.....could be an air leak, but all i changed was the fuel filter and one fuel pipe so i dident disturb any boost pipes......
in second gear its more like 4 - 4500rpm that it hesitates at

anyone think of any parts i should try changing as ive got a few spares

northerner · #7 05-06-2006, 17:41

Fuel pressure regulator or blocked fuel pump could be causes. High idle though makes me think choke unit !

datdrift · #8 06-06-2006, 14:07

just ran the diagnostics and got 3 codes.....
23 - throttle valve or circuit
24 - ????
31 - no fault

datdrift · #9 06-06-2006, 14:53

changed the throttle position sensor, and it sort of fixed the idle.....for a bit, but then it started rising again. did the diagnostics again and it just came up 44.....

datdrift · #10 06-06-2006, 16:57

took the fuel pump out to see if it was blocked at all, and it seemed fine, put a spare one in to see if any difference but still the same so i guess next is to change the fuel regulator and/or injectors......
i think it must be fueling, as the more boost i run the earlier in the rev range it happens