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Rb25Neo Crank Angel Sensor (cas)

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hey guys ive got a 1997 Skyline r33 series 2 with a RB25 Neo engine in it, ive got 1000cc injectors with a 460 Walbro fuel pump and running of a microtech LT12 ecu...

Ever since ive upgraded the fuel system a few weeks ago, ive been having constant misfires on idle and struggle to start the vehicle when its warm... also on high RPM i tend to lose power and back fire alot more on high Revs.

A few nights ago i was crusing down my street untill all of a sudden all my cylinders started to drop out one by one untill there was nothing left and the car stopped in the middle of the street on me and would not fire up again, it would crank like normal but constant and not firing, At first i thought spark plugs coil packs, so i towed it back to the workshop and put fresh sparks plugs and testes the coils were all fine, i kept chasing the problem and assumed the Crank Angel Sensor (CAS) so i tested it today and started pulsing the injectors with the Ignition on and after i put it all back in, My car started up but on two Cylinders Number 1 and 5, chased it up and all my other injectors were not getting any signal...

would this be a Faulty CAS sensor?

It is starting to leave me abit brain dead on whether i should buy a new one for $600 or keep chasing the problem... im just confused abit because when i tested the CAS sensor it was pulsing the Injectors. Any tips or advise before i spend $600 only to find out its not the Cas sensor And could of put it towards better upgrades...

Bassel Darwich

first year apprentice

Brisbane, Australia ✌

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Given your symptoms I'd suspect that the CAS is not going to be your issue. You need to do some more diagnostics before you can decide what the problem is. The Microtech might make things a little more difficult as I'm not too sure how much diagnostic data is available in terms of the ref and sync inputs. Essentially though if you're getting any injection or ignition events I'd think the ECU is getting the required signals. I'd start by scoping the trigger inputs at the ECU so you can rule out the CAS. Next I'd be looking at the injection and ignition outputs from the ECU. It could be that you've got a faulty ignitor module or something similar. Given that your problem appears to be linked to the fuel system changes I'd also be suspicious that there is something going on there. Have you watched fuel pressure when this problem is occurring?

Heys ive been going through the hand controller and says error CHK1 and 2... i had it under the passenger floor and suspesion of my passenger might of kicked the buttons and changed something on the hand controller... Aswell as i have watched the fuel reg says 2 bar but when i test spin the cas sensor the fuel reg jumps from 3 to 2 and back, could it be faulty signal from the cas? Still waiting to get a microtech adaptor so i can see more on my laptop

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