Need Help Please

[StormR34]

Good day everyone, my name is Zaid I'm new to this sight. I'm hoping some will beable to assist me. I have a skyline r34, it has the rb25det neo motor, I have an issue that nobody can seem to solve, please can someone advise or give help. I'm from south africa and we don't get the skyline this side, so I had to import mine, so not many guys have experience in fixing this car. Firstly the car was stock.when I came upon this issue,the car would loose power like it dropped a valve, but it would only happen every now and again, I had it checked out I was told my spark plugs were wrong so I did research on sights got the right plugs and even gapped it to 0.8mm the car ran fine for awhile then the same issue returned about a month later, I then replaced the coils, thinking one or a few must be faulty , once again it worked for a month then the problem returned, some said my earthing of the car was not right. I sorted that out but the problem was still there, I then changed my injectors found out one was faulty. The car worked fine for about 3 months then the issue came back and shortly after that the piston melted and the conrod cracked through the block I replaces the motor and put a spitronics management system in now my engine light doesn't want to go off and the new motor is giving the same problem. I don't know how to fix this issue. Please some advice would be great. I'm not to clued up on some of the terms you guys use so please reply like you righting to a person that knows nothing about cars. Thanks in advance

[pedro skyline]

Hi there try and check the MAF sensor first. Then

Try the coilpack loom. Then check for vacuum leaks se é if this helps

[StormR34]

Hi, thanks for the responce, I am assuming maf sensor is my air flow meter, if that is the case it's been removed since I have a engine management system in. I'll check for leaks and the loom, thanks again

[Dev RB25]

new motor, new coil packs, new ecu, new plugs, but same prob... maybe its somewhere in the fueling, fuel pump, fuel lines, fuel filter, or even the fuel itself.

If you have a buddy with a wideband, and if ur ecu (not familiar with spittronics) can do datalogs, this would be quite handy to help see what is actually happening when the power loss kicks in.

if you melted a piston i believe you could have a severe fueling issue or spark. and you covered alot on spark...

[Dev RB25]

regarding the checklight, since the management was jst done, it could be a wiring issue, is it a standalone or piggyback ?

[StormR34]

Thanks Dev, I did reply a while ago but I.don't see my reply here, not sure why, anyway it's a stand alone management, it possibly could be fuel but if so, won't a dyno pick up that. I notice my spark plugs die very quick, sometimes only lasts 3 months if I replace them then the power returns. I'm out of town for awhile so.I won't beable to check.thoughs ideas at the moment, but I'll check on the fuel

[StormR34]

When Im back

[Nismo 3.2ish]

I think running too lean can do damage and quickly, such as melt a piston, but I am just guessing ?

[StormR34]

For sure that is true, it's exactly what the mechanic said, running lean melted the piston.

[Dev RB25]

Thanks Dev, I did reply a while ago but I.don't see my reply here, not sure why, anyway it's a stand alone management, it possibly could be fuel but if so, won't a dyno pick up that. I notice my spark plugs die very quick, sometimes only lasts 3 months if I replace them then the power returns. I'm out of town for awhile so.I won't beable to check.thoughs ideas at the moment, but I'll check on the fuel

if the car was dynotuned, then yeah definitely they should have picked up an fueling issue if it was lean or rich..but since you mentioned the problem comes and goes... perhaps that is why nothing was detected...

a bad fuel pump and/or fuel pressure regulator could make the car possibly run lean, maybe that was the case with the old motor melting the piston.

[tridentt150v]

maybe the spitronics spat the dummy?