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hi guys

having a little problem with my r34 at the moment, the car keeps on stalling on me when im braking to come to a stop. ive checked everything i can think of including vacum leaks and idle control valve but cant find any faults.

could it be something as simple as air/fuel ratios, as it does need a tune but i did want to clear up the prob before i put it in.

any surgestions?

thanks

Justin

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Do you have an atmo bov installed? If you do, that's the thing causing all the stalling. To stop it, remove the bov and reinstall the standard plumb back bov.

If you don't have one installed, I'm not sure what it could be seeing that you've already checked if there's any vacuum leaks.

Do you have an atmo bov installed? If you do, that's the thing causing all the stalling. To stop it, remove the bov and reinstall the standard plumb back bov.

If you don't have one installed, I'm not sure what it could be seeing that you've already checked if there's any vacuum leaks.

NO blow off valve installed.....ive been chasing possible causes for the last couple of weekends. its starting to really get on my nerves.

check release/throwout bearing

there was an issue with my clutch that caused the same things before.

Had to keep revving it to prevent stalling.

clutch is disengaging fine. the problem happens during heavy braking and medium braking all the time.... but only when i creap up to the lights, shifting down through the gears to bring the revs back down to near idle speed then depress the brakes it wont stall then, the best way to explain it is as if when i brake it feels like the booster is using most of the air in the plenum chamber then no air to left to provide decent air-fuel ratio, although i have checked idle air control valve and can not fault it.

the problem would prob be fixed if i just tune the idle control up, but then the car would be reving near at least 1500rpm -2000rpm.

thanks

Justin

When you say you got no BOV, that's incorrect - either you have a stock blowoff valve or you got an aftermarket one.

If you got a stock one, I would check it out, check the vacuum hoses for any leaks or breakage, also use cable-ties to make sure it's fastened nicely from both ends - also remove the stock BOV and make sure that the springs (or valve whatever you call it) is working probably.

Also make sure it's plumbing back 100% to the engine.

Now, if you have an aftermarket one - make sure it's a 100% plumback BOV and not one that vents to the atmospher and this will play with the airflow/fuel mixtures and the AFM will not function right.

Secondly, like most have suggested - check your AFM to see if it's working probably - might need to resoldered the adaptor ends - or get a new AFM altogether - if you need a new one get a Z32 (from the Nissan ZX's).

Finally, if you have a frontmounted intercooler - check all the hosing and make sure that everything is tightly plugged in.

And if you can afford it and have the time, get a full retune - will help you out heaps.

Good luck mate... I used to get this problem too - found out it was the BOV, plumbed it all back and it's working fine now.

When you say you got no BOV, that's incorrect - either you have a stock blowoff valve or you got an aftermarket one.

If you got a stock one, I would check it out, check the vacuum hoses for any leaks or breakage, also use cable-ties to make sure it's fastened nicely from both ends - also remove the stock BOV and make sure that the springs (or valve whatever you call it) is working probably.

Also make sure it's plumbing back 100% to the engine.

Now, if you have an aftermarket one - make sure it's a 100% plumback BOV and not one that vents to the atmospher and this will play with the airflow/fuel mixtures and the AFM will not function right.

Secondly, like most have suggested - check your AFM to see if it's working probably - might need to resoldered the adaptor ends - or get a new AFM altogether - if you need a new one get a Z32 (from the Nissan ZX's).

Finally, if you have a frontmounted intercooler - check all the hosing and make sure that everything is tightly plugged in.

And if you can afford it and have the time, get a full retune - will help you out heaps.

Good luck mate... I used to get this problem too - found out it was the BOV, plumbed it all back and it's working fine now.

i understand completly what you are saying, but i dont have a blow off valve, i run my setup with out one. i used to have a turbo smart one (with the double trumpet vent to atmos) but i took that off and put a blanking plate on. i know everyone will say thats no good for my turbo because of pressure during gear changes ect... but thats just the way i have it. also this problem just started recently, and my setup with no bov have been like that for a while, so i cant see that being the prob.

if its the air flow meter the idle would be continually hunting, correct me if im wrong? but i will check that out to be sure. thanks for the help spunky munky

Edited by walkoau

Your afm will be getting a double reading when the pressure goes past it a second time, and hence telling the ecu there is twice as much air as there really is.

you need to tune around not having a bov and put your afm into your ic piping, or put up with stalling.

Edited by joeyjoejoejuniorshabadoo
i understand completly what you are saying, but i dont have a blow off valve, i run my setup with out one. i used to have a turbo smart one (with the double trumpet vent to atmos) but i took that off and put a blanking plate on. i know everyone will say thats no good for my turbo because of pressure during gear changes ect... but thats just the way i have it. also this problem just started recently, and my setup with no bov have been like that for a while, so i cant see that being the prob.

if its the air flow meter the idle would be continually hunting, correct me if im wrong? but i will check that out to be sure. thanks for the help spunky munky

Mate, no issue - glad I can help.

Now that's not a setup you see everyday. My advice to you is look for a stock GTT/GTR BOV and put one in - they're there for a reason to stop excess turbo surges during gear changes and protects the turbo.

Secondly, check the AFM - open it up and see if the connecting adaptor bits (sorry don't know any better to describe them) are working probably as, like I said earlier, they might need to be resoldered.

Lastly, I think your ECU needs to be tuned. I know you've been running this setup for a while with no issues, but some times it becomes a probably in the long run when the car 'can no longer cope.' For example, I went from stock BOV to a full atmospheric one - worked fine and sounded lovely for months - then about 2 months ago I started noticing the car functioning kinda weird... e.g. too lean with black smoke, a bit less responsive and then the same issue as you - stalling started happening... don't ask me why the car's taken a few months to start to react, but it just does... got a 100% plumb back one, got a mate (thanks Cheez on here) to fix my AFM and it's working like a dream now. I just bought a Greedy Emanage off a mate (thanks Slouch) and will get a full retune soon - I'm sure th car will run much better soon... some times something small can mean so much.

Now how you feel mate, but I would focus on getting this fixed ASAP as despite the car having so much power etc, what use is it if it keeps stalling - this can be potentially dangerous as well.

Cheers,

SM

  • 1 month later...
Your afm will be getting a double reading when the pressure goes past it a second time, and hence telling the ecu there is twice as much air as there really is.

you need to tune around not having a bov and put your afm into your ic piping, or put up with stalling.

Joey.............junior...(ur id name too long)

you where 100% right. on the weekend i moved my air flow meter to the intercooler piping, mounted it just before the intercoller and now problem is fixed.....yeahh... no more stalling.. it made such a big difference with the way the car runs. thanks for your help.

Justin

Guest courtney
hi guys

having a little problem with my r34 at the moment, the car keeps on stalling on me when im braking to come to a stop. ive checked everything i can think of including vacum leaks and idle control valve but cant find any faults.

could it be something as simple as air/fuel ratios, as it does need a tune but i did want to clear up the prob before i put it in.

any surgestions?

thanks

Justin

Edited by courtney

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