Jump to content
SAU Community

Idling / Accelerating Issues

PACEY

By PACEY,
in Western Australia

 Share

Recommended Posts

PACEY Collaborator

PACEY

Posted
Posted

Right then, for the first time in 2 and a half years my car is doing some interesting things.

1. When idling if i put the clutch in and put it in gear, leave my foot on the clutch, the revs increase by like, 300rpm. Then when i take it out of gear but still leave my foot on the clutch, it returns to normal.?????????Doesn't happen all the time though.

2. The worse of the two. While travelling down Orrong? road yesterday, while acceleration the revs dropped to 600 (idling). Then after about a 2 sec delay it came back up to the rpm i'd expect to do at 80kmh. ?????? It did it about 4-5 time in the space of about 10mins. I filled the tank up after work on the way home and it didn't do it again. What the?????????

Any suggestions?

Link to comment
https://www.sau.com.au/forums/topic/72592-idling-accelerating-issues/
Share on other sites
bully Experienced

bully

Posted
Posted

how low was your fuel tank??

May have some non fuel in it - i had this problem with water in fuel in a suburu my father in law owned.

We put a cup of metho in the tank, filled the car with fuel and then we could run it dry . the metho apparently stops the fuel and water seperating - we then ran it out completely never had the problem again.

Steve Grand Master

Steve

Posted
Posted

What mods do you have? the revs picking up at idle sound like they may be the NVCS kicking in. If your idle isnt stable, it 'may' activate it once the neutral switch has been deactivated.

Second problem could have been fuel surging due to not enough in the tank.

More info would be good, mods, settings etc.

Steve Grand Master

Steve

Posted
Posted

NVCS is the system nissan use that advances timing on the intake between 1050 and 4500rpm. If the revs at idle get near 1050, and the car is in gear, the NVCS will activate, advancing the timing and the revs will go up.

To test if this is the problem, just unplug the NVCS and put the car in gear. The NVCS plug is front drivers side of the head and has a brown plug. Or, you could just get someone else to put it in gear while you listed with the hood up - there will be an audible click noise when the NVCS activates.

For only a cat back it shouldnt cause dramas. 1/8 of a tank shouldnt cause dramas either with stock fuel pump.

PACEY Collaborator

PACEY

Posted
  • Author
Posted

Oh dear, the problem just got worse. Now when i come to a stop at the light and stuff the car just slowly drops revs and cuts out. It will happen 3 out of 5 times. When the car is stationary the rpm needle is constantly searching on the dial, if that makes sense.;) What the **** is wrong with my car? It seems to me like a computer issue. Like one of the senses has shat it's self and the computer is therefor going ?????? what the?.

Any ideas?

Steve Grand Master

Steve

Posted
Posted

It could be your AAC - that is your idle control solenoid at the back of the plenum. It has a brown plug hanging off it. Check the plug is properly in place, try removing the plug and cleaning the electrical contact with brake cleaner or electrical contact cleaner.

Next step is to remove it and give it a good clean. Three bolts, pretty easy. You will also need to disconnect the purple plug to do this, its the AC idle solenoid. Once removed, give it a bath in brake cleaner.

Another thing to try is keep your ac switched on, as this uses an additional solenoid to bleed extra air into the plenum - may keep you out of trouble for the while. If it helps you will need to keep the aircon turned down to coldest setting so it is on most of the time (climate control will cycle on/off to maintain the set temp).

Another thing that is vital is to check ALL your vacuum hoses, intercooler pipes etc as well. Most skylines are old and the hoses tend to perish and crack.

Hope it helps. Sorry but I am somewhat taking stabs in the dark. Most fault finding is a process of elimination.

G/L

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      Yup. You can get creative and make a sort of "bracket" with cable ties. Put 2 around the sender with a third passing underneath them strapped down against the sender. Then that third one is able to be passed through some hole at right angles to the orientation of the sender. Or some variation on the theme. Yes.... ummm, with caveats? I mean, the sender is BSP and you would likely have AN stuff on the hose, so yes, there would be the adapter you mention. But the block end will either be 1/8 NPT if that thread is still OK in there, or you can drill and tap it out to 1/4 BSP or NPT and use appropriate adapter there. As it stands, your mention of 1/8 BSPT male seems... wrong for the 1/8 NPT female it has to go into. The hose will be better, because even with the bush, the mass of the sender will be "hanging" off a hard threaded connection and will add some stress/strain to that. It might fail in the future. The hose eliminates almost all such risk - but adds in several more threaded connections to leak from! It really should be tapered, but it looks very long in that photo with no taper visible. If you have it in hand you should be able to see if it tapered or not. There technically is no possibility of a mechanical seal with a parallel male in a parallel female, so it is hard to believe that it is parallel male, but weirder things have happened. Maybe it's meant to seat on some surface when screwed in on the original installation? Anyway, at that thread size, parallel in parallel, with tape and goop, will seal just fine.
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      How do you propose I cable tie this: To something securely? Is it really just a case of finding a couple of holes and ziptying it there so it never goes flying or starts dangling around, more or less? Then run a 1/8 BSP Female to [hose adapter of choice?/AN?] and then the opposing fitting at the bush-into-oil-block end? being the hose-into-realistically likely a 1/8 BSPT male) Is this going to provide any real benefit over using a stainless/steel 1/4 to 1/8 BSPT reducing bush? I am making the assumption the OEM sender is BSPT not BSPP/BSP
    • funkymonkey
      Jacks that fit under GTR lips that can reach the subframe?

      By funkymonkey · Posted

      I fashioned a ramp out of a couple of pieces of 140x35 lumber, to get the bumper up slightly, and then one of these is what I use
    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      I wouldn't worry about dissimilar metal corrosion, should you just buy/make a steel replacement. There will be thread tape and sealant compound between the metals. The few little spots where they touch each other will be deep inside the joint, unable to get wet. And the alloy block is much much larger than a small steel fitting, so there is plenty of "sacrificial" capacity there. Any bush you put in there will be dissimilar anyway. Either steel or brass. Maybe stainless. All of them are different to the other parts in the chain. But what I said above still applies.
    • Duncan
      Mistakes were made, my R34 Story

      By Duncan · Posted

      You are all good then, I didn't realise the port was in a part you can (have!) remove. Just pull the broken part out, clean it and the threads should be fine. Yes, the whole point about remote mounting is it takes almost all of the vibration out via the flexible hose. You just need a convenient chassis point and a cable tie or 3.
×
×
  • Create New...