Monky

Good man thanks Paul. Yeah I see what you mean with the highlight, disconnected one and it did just that. I do seem to be getting a lot of knock with the hesitation, the cat light flashes sometimes on boost. As far as I am aware this is down to injector duty cylce being maxed or high knock levels? This is why I thought MAF's were dodgy as they would cause it to run lean I am sure. Abbey Motorsport are near me who are Skyline specialists (http://www.abbeymotorsport.co.uk/main.htm), hopefully they should be able to un-lock and see what is going on. I've just noticed I've got one OEM coilpack for some reason, the other 5 are Spitfires. Maybe this has happened before? Well at least we are getting somewhere, 10 stars mate really appreciate your time on this ten fold great forum... I wanna send you some beer money T

Hi Paul, Sure does, I spoke to a tuner and they said it's probably as the MAP is locked, I think this is what you were getting at. Is is possible that even though the AFM's are showing good voltage that the sensors are buggered? I've got Z32's here, shall I go for a remap? When there we can maybe swap coils, amplifier, plugs etc and see what we come up with? Cheers mate, M

Sump

Hi Paul, Am back now, here we go: 1) Sensor check - MAF 1 slightly lower voltage at around 1.0v and MAF 2 around 1.15v. Although they have voltage could the thin metal sensor be damaged in some way? 2) Airflow settings - All on 0% The car was spot on, started developing a mis-fire, got worse and now I am here. Sometimes it picks up fine, after a little drive it starts to mis-fire and as mentioned sounds like it drops a few cylinders. I just thought it was the MAF's as they are quite messy, siliconed up and it looks like someone had issues with them before but who knows. I've never changed the settings on the Power FC and when I bought the car it pulled like a train, well it should do for 600hp! As mentioned it was live mapped by RB Motorsports here in the UK. Thanks for your time on this. M

Thanks for your kind reply. I'm in London at the moment but as soon as i'm back i'll take some photo's or a video. Defo on 0, i'll also do a sensor check. Will it show results for both Maf's? Once again thanks, the car was built and mapped by RB Motorsport but before i bought the car. They are quite well known over here but regardless something isn't right due to hesitation and sounds like it sometimes drops a cylinder or two. M

Sorry to be thick how do I do this and what am I looking out for? Thanks for your time much appreciated. M

Hi all, I just want some help to confirm that it's defo my MAF sensors that are on there way out on my GTR. I have RB20 MAF's, they are pretty tired, have been siliconed up a few times from the looks of things before I had the car. I've managed to borrow a friends RB20 MAF so I replaced one of them, it did make a hell of a difference for a short while as before it would hesitate, it didn't anywhere near as bad when I replaced the one. The car was fine when I bought it but developed a slight mis over time which got a little worse. In basic, if I disconnet the good MAF, the car stalls instantly which is what I am sure it is supposed to do, BUT, if I disconnet the other MAF (old one) the car doesn't stall it just keeps running. This makes me think that it's not recognising the other MAF therefore it must be faulty? Secondly, on the power fc when I go to airflow settings their isn't an option for RB20 MAF just RB25, does this matter? The car was fine before so I'm guessing it's not an issue. When you scroll into the RB25 setting it has all the voltage values except everyone has 0% next to it, is this right? Any help is really appreciated, I'm pretty sure I've hit the nail on the head but just want some help from you guys to be absolutely sure. All the best, M

Hi all, 1) Does anyone have a wiring diagram to convert from RB20 MAF's to Z32 MAF's on a GTR? 2) I'm running power fc, will the car need a remap or can I simply select the different map and it will run fine? The last option I have on the power fc is VG30, is that the correct one for Z32? (Other options are stock 32/33, power something, RB25 and VG30) 3) If VG30 is the correct setting, how do I select it? I can scroll down to it, get into the parameters but when I come out, exit, and go back in it goes back to RB25? Thanks all, M

Thanks for the info defo going to get it looked at as unsure what else it could be. I thought though when a MAF/AFM fails it effected idle and would also give lean conditions, this was a common problem on the Scoobies. I did clean my AFM's with carb cleaner and may have gone a bit overboard. Regardless I have Z32 MAF's on the way as the current ones are silconed where they have cracked and fell apart when I took them apart! Once I have the new Z32's it will need a remap so will get everything checked and leave her to rest for now. M

Hey mate thanks for the fast reply. I've just tried the old plugs, still just as bad. When I rev the car on idle it hesitates, after 4k it clears kind of but a real mission to get up there due to stutter. I'm getting lots of knock just from reving on idle, when it hesitates it knocks and the dash light flashes as power fc is detecting knock around 3k. Does this give any clues if its knocking? I'm thinking dodgy mafs as she now struggles to idle and i'm getting knocking maybe from lean conditions, that's what a dodgy maf did on my scooby, any ideas?? M

Hi all, I'm currently running greddy 8's in my RB26 which are made to JIS (slightly longer plug when compared to ISO). The NGK BCPR8ES are also made to JIS but I can't seem to get them here in the UK. They only do 6's and 7's and I need to colder grade (600bhp 1.5 bar HKS 2860 7's). Does anyone know if they are still made, I've been told they are discontinued. I've tried BCR8ES & BKR8EIX but both of these give really bad hesitation, my guess as they are shorter ISO. With the Greddy plugs it was completely fine, it started to get a intermitent mild hesitation low down coming on boost so I thought spark plugs could do with a refresh whislt not looking that worn. I swapped plugs for the slightly shorter ones, still grade 8 and it was 10 x worse so I attributed the hesitation to spark plugs? Car is running spitfire coilpacks. When I drive the powerfc is setting off the cat light when it hesitates even just plodding around slowly, barely on boost. I know the light flashes either if you have maxed injector duty, too much knock or air flow. Knock levels were reading high around 40, I thought powerfc flashed if it was above 50? My car does have agressive cams and makes a bloody lot of noise but am still concerned as to what it could be. The car also won't idle properly anymore, it used to be around 1100 with very lumpy idle but now it struggles at 800 and tries to stall all the time. I'm going to try the old plugs to see if it makes a difference with the hesitation and will report back. Thanks, M

Thanks for the detailed replies everyone. What I'm doing now is running 0.5l extra which helps reduce the oil pressure drop when accelerating in low gears. I'm running relocated filter, oil cooler, tomei baffles and N1 pump. I guess without running the extra oil it can't return to the sump quick enough. Even if I leave the car after a long run for 45 minutes plus it still barely registers on the dipstick. I know Sydneykid mentioned it would take a while for it to drain back to the dipstick area, but if it's showing little oil in the sump isn't it wise to add a little more? Now that I run 0.5l more, when I turn the car off when hot and check after a short while the level is 100% to the max. I basically topped it up when warm until it went to the max. When I check when cold it's up at the start of the bend, when I check when warm it's at the max line. Oil pressure drop has also been reduced. I will also look at replacing the Greddy gauge or at least find out what needs replacing. Will also make sure I don't warm up idling now I know that the gauge is buggered! Cheers all this is a top forum! M

Okay Cheers Paul, did you get a drop in clutch fluid from the master reservoir? I've checked mine daily and it hasn't moved, still full so not sure if I have a leak although there could be air in the system, it does look a little dirty as well. Would you suggest a clutch bleed and refill before anything else? Fingers crossed this will cure it, what about adjusting the biting point out a little? And original poster let us know what it was! :-) M

Took ages for me on my 15" laptop screen with crusty wireless connection but looks ace

Nice