Jump to content
SAU Community

Cant Work Out Why My Car Has A Low Idle And Stalling On Hot Starts


Recommended Posts

cold days it is fine, but if i drive somewhere say to the shops, it reaches operating temperature then come back 5 minutes later it acts up, or just on hot days.

ill start it, it will idle low when i accelerate it will sound like its running on 3 cylinders and pisses out black smoke, if its doing this in stop go traffic it will run like shit stall & piss out black smoke

i know the black smoke means un burnt fuel

anyways the cars history

r31 skyline, rb30e,

2 years ago reconditioned the head at my work shop, had cam reground, raised to compression from 9:1 to 9.6:1, stock computer

year ago converted it to manual,

since the manual conversion its had issues, replaced start motor, alternator, all new belts, 2 afm (1 new), new bosch coil, new thermostat, radiator cap, radiator hoses, 2 dizzies (1 was out of a vl and was told the wiring is slightly different to the nissan)

every 3 months/5000kms i change oil and filter, every 6 months 10,000kms i change oil, oil filter, spark plug leads and spark plugs, every year 20,000kms new fuel filter, air filter etc

i have changed just about every sensor, bought all genuine, sprayed 2 cans of carby/ throttle body cleaner, AAC is clean and carbon free, had injectors cleaned

i replaced the reground cam with a standard cam

ive had numerous mechanics look at it and its either not been an issue when they had it, or they couldnt find anything

im starting to think maybe a cylinder or to has excesive clearance or the rings are on their way out, but it doesnt use any oil

any1 got ideas?

Not familiar at all with RB30s so this might not be any help at all to you, dodgy ignitor modules malfunction when they get hot, though usually it results in misfiring, might be worth also finding a better ground for the ignitors ground wire.

For the RB20 (yes, I know you have a 30E, but I don't have the manual for a 30E), difficult hot starts can be caused by faulty temp sensor, or fuel pressure.

Since you've replaced the engine temp sensor, maybe try removing the vacuum line from the FPR to get more fuel pressure.

And if the engine can't spin fast enough, due to faulty / dying battery.

  • 4 weeks later...
I'm pretty sure they have an ignitor module - little black box on the side of the dizzy body.

solved,

my thermo fan that came with the car didnt work so i wired up my own thermo fan, found out the sensor that tells the computer that the thermo fan needs to come on was confusing the computer, ust so i just disconnected that switch

thanks everyone for their help and suggestions

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Latest Posts

    • I was just driving into work and while on my drive, I went to accelerate and noticed the car would sputter/hesitate and I’d hear a few pops from the exhaust before it started going faster. Then I also noticed that when I push my clutch in, the car would die. This all started happening today. Any ideas?
    • That is a lovely Volvo, just saying. Yes I should have got an 260RS when they were cheap. I do regret now.
    • ^ lots of good points made above. The thing is, "aggressive" or "flush" fitment is relative depending on how much you have been influenced by social media. My starting point is always "look at the Nismo RWD specs". That is where you should start, then start measuring as GTSBoy as sort of mentioned, because every car will be slightly different. My 8.5"+35/9.5+38 will not be "flush" enough for you because you want more "pumped" look, which is why you measure. Tyre sizes and brand/models also make a difference. Some tyres are more chunky/square, some are more rounded. That means you could get away with more aggressive offsets without rubbing. But then it also depends on your ride height. Also depends on how much your car copped damage before being shipped from Japan. So it goes back to measuring your car yourself and determining what can work. Those Nismo specs are used bacause it's a safe spec for standard car (suspension. body) with chunky tyres. But then I put 265/35 wide tyres on R34 GT-R wheels, and currently run 285/30 tyres on 18x10 wheels.
    • Sounds pretty awesome. I recommend creating a new build thread and posting all your goodness in there.
×
×
  • Create New...