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R32 barely runs under load

Sooo... My friend/customer has a really neat 89 m spec 20DET manual and I've offered to fix it up on the cheap because he's been f**ked around for a while and it's about time the car seen some road time. The car will rev on the spot clean and sharp without the slightest miss to 5.5-6k before it drops Spark (can hear the unburnt fuel popping in the exhaust) and when test driving it is barely driveable (as in 20kmh a struggle) with any throttle basically resulting in misfire and breaking down. Much to my dismay I'm now at the the swap parts and see stage of mechanics, after diagnosing the car has not given any obvious stuff. I have changed the plugs to BPR6ES-085 (.85gap) the coil packs have been changed by the owner less than 12months ago to OE style aftermarket coils. I have also had parts from a perfect running r32 gts-t swapped one at a time these include AFM, ECU, Igniter and Cam Sensor. I have checked the white wire supplying the the igniter for voltage at idle (14v) and under load (13.9v) and also checked the timing belt which is certainly old but all timing marks line up at 0 TDC. Our Autel Maxisys diagnostic tool has Nissan consult also which the ecu has no stored fault codes using the tool and putting the ecu in factory diagnostic mode it displays 55 currently although the consult port does continue to disconnect form the unit due to "improper connection". During live data the TPS reads .4V at idle and 4.2V wide open the ecu coolant sensor reads around 70ish degrees the rpm count matches the tacho and afm and I used the tool and a timing light to set the timing to 20 BTDC and the idle is at 800RPM. I believe the issue is related the connection problem at the consult port is going to lead to the actual problem (happy to be proven wrong though) and I'm leaning toward a earth or wiring issue with the car, also there has been moisture coming in through a slight leak in the front window if that helps. Hoping someone with some skyline experience can throw some good suggestions out there please ?

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Also thought I should add the coilpack wiring is a new aftermarket loom and the car has been fitted with an older 040 fuel pump from a silva drift car... this is also something that bothers me about the car as there seems to be excessive fuel although the owner assures me it went ok for a couple of months after it was fitted before the trouble really started and ... although that said it's never been an outstanding performer since he's owned the car. I have wondered if the fuel reg has given up due to the massive fuel pump making it bypass and/or the oxy sensor causing the ecu to run rich which results in tonnes of fuel due to the overbearing pump. 

Edited by Spark Automotive
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What do you mean by OEM style coils? The only coils we like are proper OEM or Splitfires. The rest are varying degrees of rubbish. Can you swap out the coils from the known good car (assuming they are the same?  BCPR5ES should have been fine but plugs are probably not the problem. O2 sensor should not be a factor under power. Do you have a fuel pressure tester? More likely to suspect too little rather than too much fuel. Not a fan of putting old fuel pumps of any sort in a car - they are a hassle to fit and new pumps are quite cheap so would prefer to do it once and be sure. Have you pressure tested the intercooler  piping? Pull the hose off the turbo and put some kind of fitting with a tyre valve and make sure there are no leaks up to about 15 to 20 psi just to be sure.

thanks for the reply, 

I'll try the coil packs today I was aware that OEM or split fire was the preferred choice but I would have thought the even the cheapo ones would offer an improvement over clapped out stock coils... that said I'll grab the coils from the runner and check the fuel pressure and report back. 

This one is solved... Brought a EFI testing kit today and the fuel pump is smoked. 38 psi at idle 44 vac removed and under load it drops off to 15 psi I'll get a new pump ordered in today and bang it in. Swapped coils too and no difference at all between oem and the ones he had on there so that's a bit of a positive I guess the car is stock though so I'd imagine the won't be any good once he adds extra boost into the mix.

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