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Hey guys,

Got a new fuel pump last week car runs perfects then this week i have the same problem i was trying to get rid off for quite some time.

From 2nd to 3rd gear my car splutters and has like a one second delay then has to build up boost again.....also if i rev my car all the way out it hits about 4500rpm then the car climbs up the speed extremely slow like some on has grabbed it around its neck and is choking it.

When my car did run perfect it was extremely fast now its slugish.

I did a ECU test and it comes up saying "34" Knock sensor but i dont think this would be the issue?

I got a RB20det in my silvia with a front mount, BOV, Pod, Splitfire coilpacks, Iridium Sparkplugs, 12psi, 500HP fuel pump brand new and also a turbo smart boost-tee manual boost controller they ones u wind...u think that could be the issue?

What do u think it could be.

Thanks guys please help.

- Luke

Edited by RB20DET_Silvia
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I did a ECU test and it comes up saying "34" Knock sensor but i dont think this would be the issue?

If the ECU is getting error 34, then the knock sensors are either unplugged or faulty. This means the ecu will be using the safe fuel and ignition maps, this means retarded ignition and rich fuel mixtures so that will be why your car feels so slow.

I would check the connections for the knock sensors first, could just be unplugged or need a bit of a clean. If not then you will need new knock sensors.

My ECU was coming up with code 13 which was the Engine Coolant Temperature Sensor - i read up further on it and it seemed to be controlling the amount of petrol flow depending on the car's temperature.. I checked the plugs and they were cooked..So i rectified it and ECU came up with code 55 but the car still stutters/starves up top end..

I remember someone saying that one his tuners grounded one of the ECU pinout's as a 'temporary' fix..which? I have no idea..

Im going to get my car put on the dyno to diagnose the problem..I'll let you guys know how i go..

RB20DET Silvia - i suggest you check your plugs/sensors as they may have corroded etc; over time..As a rule of thumb, as soon as the ECU comes up with a fault, it should be looked into ASAP and not be put into the "but i dont think this would be the issue" bin :)

Merry Xmas

i'm having the same on my skyline r33 s1... it's been going on for about 3 months now.. feels like the car has it's hand brakes on! i've tried everything! but still nothing. problem is still there! it's annoying not knowing what it is.....

hey just wondering how do you find out the ecu thingy. coming up with numbers??? the codes i mean..

thanks

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