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hi guys, need help to find out what the hells going on with my engine... lol, car is a r33 gtst s2 latly the car has been running fine but sometimes and for the last week im having engine problems. if and when the car wants to start, it will only rev to 2500 rpm.

somedays it will do this for 5 min to 30 min but pritty much this last week its been doing this,

can anyone help me with this issue???

have you tried anything to fix it yet?

save people suggesting things you have already tried

nah mate havent done anything yet, just seeing if anyone has had this problem first so i can do it myself... would of taking it to a machanic but dont have time... and being a sunday n all... got a perfictly good garage, was just gonna start cleaning out some hoses and sences, but if ive got a good idea on where to start that would be good too.

What do you mean by won't rev past that, does it struggle when it gets to 2500 or does it try to stall or what?

Maybe a boost leak somewhere, causing overfuelling?

Hook up a boost gauge to it and see what is going on with the turbo. It sounds like it has something to do with it given it's happening around the point where boost comes on.

What do you mean by won't rev past that, does it struggle when it gets to 2500 or does it try to stall or what?

Maybe a boost leak somewhere, causing overfuelling?

Hook up a boost gauge to it and see what is going on with the turbo. It sounds like it has something to do with it given it's happening around the point where boost comes on.

nah the car works fine, it doesnt struggle at all it just wont rev past 2500rpm. just cuts out like its restricting itself. like while driving i have to keep it under 2500, it such a pain in the ass... lol

it use to do this a few times every cople of months but its been a week non stop now, and it sometime takes for ever to start, from 5 to 30 min...

What happens if you accelerate real slowly past 2500, i.e. no boosting of the turbo at all? Can it be done? It sounds like a fuelling supply issue to me thus far...need more symptoms to diagnose further.

sounds like it's in limp mode. this can be caused by a dodgy afm. try unplugging the afm and see if it makes any difference to how the car runs.

also try disconnecting the battery to reset the ecu. might also be worth checking the fault codes.

What happens if you accelerate real slowly past 2500, i.e. no boosting of the turbo at all? Can it be done? It sounds like a fuelling supply issue to me thus far...need more symptoms to diagnose further.

nothing happends it just stops at 2500 while accelerating and still makes boost, well a lil... but if im in 5th gear doing 80kpm (top speed 90kpm when this happends) and drop it down a gear or to 2nd it will still deaccelerate through the revs and with the foot to the floor it will only come back when it comes to or under 2500. it just restricts itself from going past 2500.

ill give the battary ago to see if the resets it... will let you know...

nothing happends it just stops at 2500 while accelerating and still makes boost, well a lil... but if im in 5th gear doing 80kpm (top speed 90kpm when this happends) and drop it down a gear or to 2nd it will still deaccelerate through the revs and with the foot to the floor it will only come back when it comes to or under 2500. it just restricts itself from going past 2500.

ill give the battary ago to see if the resets it... will let you know...

yer nah the car is still doing it, tried everything....

ill just take it to an auto machanic. and see what they come up with.

sounds like it's in limp mode. this can be caused by a dodgy afm. try unplugging the afm and see if it makes any difference to how the car runs.

also try disconnecting the battery to reset the ecu. might also be worth checking the fault codes.

+1. Complete AFM failure/ failing is most likely to cause this.

+1. Complete AFM failure/ failing is most likely to cause this.

ok i tryed the fault codes and its the afm thats playing up, i think theres a wire some where in the loom thats loose or needs replaceing. cus i fiddled around with the loom to the afm and o2 censor, and finaly after 2 weeks the car started to rum fine again but only to where i was going, and onec i started it up again, it started doing the same 2500rpm bullshit.... damn.... but does anyone know any good way of cleaning out a afm?

it may be a damaged solder inside the unit. if you happen to know someone with a s2 r33 who will let you borrow the AFM to try out is going to be the best solution.

also don't bother looking at the o2 sensor when trying to diagnose the problem. it does next to nothing and the car can be driven without it even being hooked up (i did for a few months). your fuel economy just won't be as good.

ok i tryed the fault codes and its the afm thats playing up, i think theres a wire some where in the loom thats loose or needs replaceing. cus i fiddled around with the loom to the afm and o2 censor, and finaly after 2 weeks the car started to rum fine again but only to where i was going, and onec i started it up again, it started doing the same 2500rpm bullshit.... damn.... but does anyone know any good way of cleaning out a afm?

spray contact cleaner on the filamint in the afm n blow on it with a compressor, not to hard thou. this usually improves fuel economy too. give that a go n c if it works. also it takes a few re starts of the car to reset the error codes in the ecu so maybe just reset it first to c if it goes away. if this doesnt work borrow an airflow meter off someone n see if it fixes the problem if not check the wiring. also buy a rb25 workshop manual on ebay. makes things way easier.

  • 2 months later...

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