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Idling and gear problem

JAPCAB

By JAPCAB,
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JAPCAB Proficient

JAPCAB

Posted
Posted

Hi guys,

Got two problems, i'll start with the idle. When i turn on my car etc everything is fine, however the idle is supposed to be set at 1K, however it bounces up and between about 600 and 1K. Occasionally it will stay at 1k when idling, but more often than not it will bounce around. I have continued to drive it and it goes ok. Is this a big problem?

Secondly, with my 1st gear, say i'm sitting in some traffic, i pop the gearstick into neutral, and when its time to move again, i put the clutch FULLY down to the ground, go to move the gearstick into 1st; but it makes a funny grinding noise before engaging into the gear. The grinding noise only occurs for a second or two and i can feel it in the gearstick. I only get this problem in 1st gear. It doesn't happen all the time luckily, but every say....20 odd times it will do it. Someone has told me sticky clutch, another has said cogs on 1st gear ****ed.....any hints?

Thanks guys.

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Feryha Collaborator

Feryha

Posted
Posted

If the 1st gear grind other gear when shifting, it must be syncro for 1st gear wear out

Hi guys,

Got two problems, i'll start with the idle. When i turn on my car etc everything is fine, however the idle is supposed to be set at 1K, however it bounces up and between about 600 and 1K. Occasionally it will stay at 1k when idling, but more often than not it will bounce around. I have continued to drive it and it goes ok. Is this a big problem?  

Secondly, with my 1st gear, say i'm sitting in some traffic, i pop the gearstick into neutral, and when its time to move again, i put the clutch FULLY down to the ground, go to move the gearstick into 1st; but it makes a funny grinding noise before engaging into the gear. The grinding noise only occurs for a second or two and i can feel it in the gearstick.  I only get this problem in 1st gear. It doesn't happen all the time luckily, but every say....20 odd times it will do it. Someone has told me sticky clutch, another has said cogs on 1st gear ****ed.....any hints?  

Thanks guys.

Genesis® Grand Master

Genesis®

Posted
Posted

i am having the same problem recently with my idling as well, but ONLY when the air-con is turned on. When i give the car a slight rev, the rpm will drop as low as 600 before bouncing back to 1000 again...

my guess is the belt or the fan clutch but would like to heard more comments...

thks

wrxhoon Grand Master

wrxhoon

Posted
Posted

japcab , put ur foot on the clutch wait for a few seconds then put it in first and see if it grinds then but it sounds like worn syncro in first gear . u dont want to fix that unless it gets realy bad . to repair u have to remove the box to replace the syncro and while u are at it u replace the bearings too .

JAPCAB Proficient

JAPCAB

Posted
  • Author
Posted

Yeah i've tried that heaps of times, like leaving the clutch pressed in firmly b4 moving into gear and it still does it. sounds expensive to repair anyhows though - i'll get my mechanic to check it out. thanks. with the idling problem my mechanic has recommended new sparkies...lets hope that fixes it up

japcab , put ur foot on the clutch wait for a few seconds then put it in first and see if it grinds then but it sounds like worn syncro in first gear . u dont want to fix that unless it gets realy bad . to repair u have to remove the box to replace the syncro and while u are at it u replace the bearings too .
  • 2 weeks later...
druzilla32 Mentor

druzilla32

Posted
Posted

with the ideling try some new plugs..

Mine use to idle from 800 to 0rpm, battery light came on, then it would start back up... i was going about 160kmph (on an open road way out west) and i put it in neutral, the car then turned off... thats scary cuz power assisted breaks and power steering also goes off.

its not too bad now with the new plugs in. also clean the afm and reset the computer.

blind_elk Grand Master

blind_elk

Posted
Posted

Try an oil change in the gearbox. The oil might be getting too thin, or too low level, to stop the gears rotating when you disconnect the 'box from the engine.

As for the idle, clean the AAC valve, clean inside the throttle body around the throttle butterfly, check for air leaks in the induction plumbing.

R31Heaven Proficient

R31Heaven

Posted
Posted

The idle problem will be the AAC valve being gunged up with carbon take to it with some carby cleaner. GenesisR32 the Air conditioner problem will be the FICD valve next to the AAC valve this controls the ideling when the A/C is on, it could have the same problem. Would be good to make cleaning these a part of a service. The gear box problem will be the Syncro not meshing properley, putting a good oil like Redline may fix the problem but if the syncro has gone you will need to replace it cost around $400 in counrty Vic may be cheaper in City. to get around it for aa while learn to double clutch this will get you around it until it is fixed.

JAPCAB Proficient

JAPCAB

Posted
  • Author
Posted

I popped in some new bosch spark plugs - they have 4 prongs on them instead of 1, definately a performance gain, the old plugs were ****ed. However with the idling it seemed to be A-OK but its doing it again - however not as bad. I removed and cleaned and refitted all the intercooler and induction piping, all seems to be ok there too. Where do i find the AAC valve btw? (sorry i'm pretty new to all this shit) any other ideas guys?

Thanks for all the help so far its been great

KamikazeR33 Grand Master

KamikazeR33

Posted
Posted

guys also u might wanna get the diaphram checked out in ur idle circuit, they seem to go sometimes so u will get stalling etc

also these go when u use more than 20psi boost..... i cant wait to find out how bad it will be (or not so bad) when i get my car back soon

Craved Grand Master

Craved

Posted
Posted

i've got a similar problem now, but only since i had the battery disconnected for 2 days! mine will rev down to 600rpm sit there for about 2 seconds then try to stall, have to keep the revs up. shouldn''t be aac or oxy sens or afm, but i'll clean those and report back. but any ideas people?

where is the easiest way to increase idle rpm?

R31Heaven Proficient

R31Heaven

Posted
Posted

Tha AAC Valve sits at the back of the plenum it is a round cylinder with a electrical plug on its side with one conector veritical the other horizontal, and two small screws holding it in. Be careful when taking it out as there is a small spring behind the valve inside, it can drop out if the unit is not kept together.

Craved your problem sounds more of a Vacuum leak, didnt knock any hoses off ? did you touch anything else but the battery? like the intercooler hoses/conection?

Craved Grand Master

Craved

Posted
Posted

yeah i thought of the hoses, but with the battery in the boot i dont think it was related :(

will check it out, had problems awhile back, and after that it always idled real high - almost 1600rpm then occaisonally at 1200rpm, now it sits around 600rpm as posted! is the idle electronic or is it that bolt that stops the throttle moving back too far?

R31Heaven Proficient

R31Heaven

Posted
Posted

Your idle adjustment is on the back of your plenum, dont adjust the screw on you throttle body that is factory set and will stuff every thing up if adjusted. if you car tends to rev high, it is uasaly the Air reg that causes this in the front of your plenum, you can test this by pinching the hose that come out of it. Yor Revs should drop.

grepin Experienced

grepin

Posted
Posted

Hi all I have a idle problem from cold start. Wants to rev a 2k rpm until warm then OK with some hunting on occasions. The AAC is fully adjusted in and still revs high. Has happend since new turbo, plenum, throttle body fit up and yes above 20psi boost on occasions. May it need a clean or new diaphram or even the HKs idle stabilizer. PFC temp/idle settings seem OK.

Thanks

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