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tell ypu guys wat. As you guys know about 2 ,omths agp i wemt amd got ,y car tumed with power Fc . Got the car back and it ran perfect. But from time to time the car will feel like it lost power for a millisecond amd i called racpace which is my tuner. And they said that its the power Fc cos its too sensitive. Its getting reading from the sensors all the time and sometimes the sensors send a blank info to the ECU therefore the "loss of power for a split millesecond. I dont know how true is it though. It doesnt do it all the time though. So...

If it's what I'm thinking, it's a typical Power FC thing, every car I know that runs a Power FC has a mid-low RPM miss in it, it only does it for a split millisecond. Nothing really to worry about...

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If it's what I'm thinking, it's a typical Power FC thing, every car I know that runs a Power FC has a mid-low RPM miss in it, it only does it for a split millisecond. Nothing really to worry about...

ok thanks for confirming this pal

If it's what I'm thinking, it's a typical Power FC thing, every car I know that runs a Power FC has a mid-low RPM miss in it, it only does it for a split millisecond. Nothing really to worry about...

I have had 5 Skylines with Power FC's, 2 currently, and none of them have that problem. It is easily eliminated with some attention to the off boost and low boost load points on the ignition maps. The default maps are a bit retarded in several places and most tuners only pay attention to the on boost load points and ignore the others.

>_< cheers :happy:

This is a little off topic but still in the same ball park so I'll save starting another thread...

Now I don't know if this is a missfire or just the ecu cutting power just before a shift (I know some auto toyotas do this to save the auto on wot gear changes). But basically I put my foot right down and at pretty much 6000rpm it sounds like a rev limiter but faster and smoother (if that makes sense at all) and then shifts and the process starts again. There is no missfire from idle to anywhere else in the rev range at all and runs perfectly even under boost, just at this point. But if I put the car in netural and rev it to this point it will do the same thing. Its really hard to describe but missfires are usually harsh (depending on how servere they are). It really feels and sound like a cut out from the ecu. But I wouldn't think it would do this with me just free reving it. And usually with a missfire if your just revving the car it may not miss until you put some load on the motor.

Any ideads....

I've got a set of iridium's which look perfect and gapped to .8 (auctuall I've gapped them down further atm to see if there was any difference) and checked the coil packs over but I have another set I can try if need be. But it doesn't seem like a usual missfire.

All auto Nissans have ignition retard and/or cut on the gearchange. It helps protect the band/clutchpacks from excessive loading. It also smooooths out the gearchange.

>_< cheers :happy:

If it's what I'm thinking, it's a typical Power FC thing, every car I know that runs a Power FC has a mid-low RPM miss in it, it only does it for a split millisecond. Nothing really to worry about...

after tuning more PowerFC's than i had hot dinners (especially of late) i am yet to experience this miss..... i figure there is a hole in your map somewhere.

after tuning more PowerFC's than i had hot dinners (especially of late) i am yet to experience this miss..... i figure there is a hole in your map somewhere.

So wat you are saying is theres a "flaw" in the tune?

All auto Nissans have ignition retard and/or cut on the gearchange. It helps protect the band/clutchpacks from excessive loading. It also smooooths out the gearchange.

:mellow: cheers :laugh:

Thats what I was thinking (as I know toyotas are the same). It doesn't really bother me as your basically out of the power band by 6000 anyway (with standard turbo etc....) just wanted to make sure that its nothing else. It really didn't feel like a miss. But what about people doing the manual conversion and keeping the Auto ecu. I did the same thing when I converted my 180 from manual to auto and there was no problem. But I don't remember there being a hard cut on gear changesin that car but that was some time ago now. What did strike me as being strange though as it would hit this cut at the same point even if I had the car in netural but. Now for the people that have a shift kit (like the MV automatics one for eg.) does this make it more noticable or actually improve it. Also (not that I want to do it at this stage) can you disable it?

That’s has been my experience. Although "flaw" may be a bit heavy, more like " an untuned area".

:mellow: cheers :laugh:

If thats the case how do you repair this problem? Take it back to the tuner for a retune?

If thats the case how do you repair this problem? Take it back to the tuner for a retune?

Yep, tell him the rpm and load where the problem occurs and he should be able to fix it in a few minutes. The Commander map tracer function is good for performing that diagnosis.

:) cheers :D

Yep, tell him the rpm and load where the problem occurs and he should be able to fix it in a few minutes. The Commander map tracer function is good for performing that diagnosis.

:) cheers :D

OK Sk will do it when im back into the country. THanks

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