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

Just heard back from RB Motorsport, they did indeed drill the 5 holes into the sump wall. Strange one eh, I'm using 15w 50 silkolene which is pretty gloopy but even then it shouldn't take this long, they said no more than 5 minutes when the oil is up to temp. M

@ MrK - Thanks, going to get one as well :-) @ GT - I can't believe it's that cool either, but then why does it take so long to drain past the baffles, i.e. overnight unless femno is on the money with the holes but I can't see someone like RB getting it wrong, awaiting there reply. Does anyone know if it's physically possible for the oil to be at 30 degrees after an hour of driving, if not then no doubt then temp sender is foobared. @ Moodles - Again thanks, I'll replace the sender first, make sure the gauge is 100% accurate then re-evaluate everything. It gets quite cold here so a thermostat is really needed although I can't believe the gauge is reading right, although it would explain the oil taking so long to drain but even at cold temps it shouldn't take that long to get passed the baffles. M

Cheers Paul, mine may not be the same as your issue as I don't get any crunching just hard to get in gear, like the original poster. I'm gonna PM him to see what he found in the end. It's not all gears, well all a bit stiff but esp 1st, 2nd and 3rd. DS what symtoms are you getting, crunching, hard to get in gear or both? M

Thanks for the reply Paul, do you think having air in the system contributed to your clutch failure or would you say it was worn regardless? I'll have a look at my slave and master shortly and see anything dodgy. My car is running just shy of 600hp so it's possible mine is just worn from use. M

@ blind - Thanks for the reply :-). I never check oil levels after immediate shut down as obviously it needs time to drain, I'm talking 10-15 minutues later not instantly. The 5w40 I was referring too was Shell Helix, currently using Silkolene 15w50 so the rates are quite different and thought it may be worth a try. What I'm saying is that even after 1 hour of motorway driving the oil temp gauge will only show 30 degrees unless the gauge is faulty but this would explain the length of time the oil takes to drain back over night. I just check levels when cold and make sure 100%, I then monitor oil pressure while driving. @ Moodles - Star! Did you find you were running abnormal oil temps, i.e. too low? I'm going to test the gauge/sensor first, make sure it's accurate then look at blocking the oil cooler to see if the temp rises. @ Femno - Again thanks for the help, I didn't install the baffle kit. Everything was done by the previous owner, and he had the engine built at RB Motorsport here in the UK. They have a good repuation here and would be surprised if they didn;t do this but I will ask the questions regardless. It's not a massive problem as I know there is plenty of oil in there but not being able to check true level inbetween driving is a pain as you can imagine! Is it even possible to run at 30 degrees oil temp after an hour of motorway driving, surely it would be higher? I would expect at least 50 degrees even with a good oil cooler installed. I've had oil temp gauges on many cars and have never seen this low even with an oil cooler installed. Cheers, M

Yeah what was the verdict I have the exact same problem, 1st and reverse are almost impossible which makes traffic lights interesting. Can you let us know what it was, from what I have ready usually clutch related i.e worn cover, pressure plate or both. I'm running a OS Giken twin plate which has already been refurbished back in 2006, loooks like it's time again! M

Hi all, Right I found out whats going on! It's what I thought with a slightly different twist. Basically the oil isn't getting up to temperature, therefore it takes a huge amount of time for the oil to drain past the baffles back to the area where the dipstick goes in the sump. This makes it looks like there is no oil after starting. I'm looking into getting a oil thermostat or maybe using something like a 5w40 instead of the 10w50 to help the oil get up to temp quicker. At present I have to sit for over 30mins at 2k to get the oil to 60 degrees! Once it's up it stays up but if you don't do this it will never get up to temp, I guess due to overcooling? Also the oil cooler is a laminova unit, does anyone know if you can get thermostats for them? Cheers for all your time. M

Hi guys, Thanks for the replies. @ Moodles - Do I still fill to the hump even if I have the tomei baffles? From what I was told you only do that if you have a completely stock sump, i.e stock baffles where as I have tomei baffles. It's roughly another litre to the bottom of the hump so I can add it if needed I just wasn't sure as people on the GTR forum using the tomei baffles were telling me to fill to the normal level regardless? @ R31 - No catch can, it just has the normal breather pipes with the last vented to atmosphere, there is no oil coming from this pipe, no residue at all. I thought at first the oil was being retained in the head but surely it would come out from the breather pipe. I've read of people empyting a litre of oil into there catch can on a drag run due to oil retention in the head but seeing as I have no oil collecting it surely can't be this, the head must have a tomei restrictor. @ RR - The car has a remote oil filter kit yes and it also has an oil cooler but surely it can't retain 1.5litres +? To give you an idea, I leave the car overnight so oil has been allowed to drain. I check in morning, engine cold, oil level is 100% at the max line. I literally run the engine for 5 seconds, turn off and re-check and oil level on the dipstick is just touching the very bottom, as in not the low level marker right at the bottom? Does anyone else get this exact problem with Tomei baffles? The Tomei baffles have trap doors so I assumed it just took a long time for the oil to seap back through to the dipstick area. Will get there in the end just a little concerning at the momemnt!

Below is a picture of a stock sump with the tomei baffle kit. I've circled in red where I think the dipstick goes. If the dipstick does go here then no wonder it shows no oil after running. All the oil is retained around the oil pick up in the square and it must take a while for the oil to drain back where the dipstick would go. This would maybe explain why it shows no oil after turning off but does show oil after leaving it over night. Does that make sense?

Hi all, Trying to get a better understanding of my cars setup and wondered if anyone could help. I did a lot of research on my engines build and know that it is running a tomei baffled sump (stock sump with tomei baffles) and a N1 pump, if anyone could answer these questions I would appreciate it: 1) I'm aware that I need to run my oil level higher than normal, just before the hump on the dipstick, is this correct? I still have a stock sump only with Tomei baffles. Are you only meant to overfill oil on track with a stock sump? 2) Very very occasionally I have noticed oil pressure dropping in the lower gears on WOT (running circa 600hp) to around 2.5 bar, I assume this is oil surge. Even though I have the tomei baffles I take it this still isn't enough and ideally I need an extended sump? Most of the time circa 6bar. Most importantly: 3) When I check oil when cold the level is 100% fine, I then turn the engine over and literally re-check it there and then it barely registers on the dipstick. Now I know their is oil in there 100% but why does it do this? Is it something to do with the baffles and is the sump literally being sucked dry, is the oil stuck in the head? The car also has an N1 oil pump. I know that some fit drains from the head back to the sump but do I have an issue? It has a restrictor as well. I'm just worried about what I should be doing as the engine has had a small fortune invested and it wasn't be the previous owner so hard to ask the questions. It just seems strange that it's not registering on the dipstick. If I overfill to the hump, run the car, re-check then the oil level is 100% fine but only when I overfill. If I don't overfill it shows nearly nothing and takes a whole night of standing for it all to drain back. Any help really appreciated as I am a little confused! Thanks, M