Idle issues

[Alienfish360]

My car has gone a little funny since I replaced a dodgy throttle body.

It's cold idle is between 1800 - 2000rpm, which is insanely high!

And the warm idle is at 650rpm which is bang on what it says in haynes.

However, how can I drop the cold idle? Also, when I dip the clutch and put the car into gear, it revs from the 650-700 to arond 1900rpm without lifting the clutch, as soon as that lever goes into a gear it revs up??

Almost, as if it's going on choke when I select a gear, anybody got any ideas?

 

[sonic]

the clutch cable isnt interfering with the accelerator cable at all is it Phil ?

 

[Alienfish360]

not that I can see..... but this wouldn't affect the high cold idle though would it?

 

[sonic]

no i wouldnt imagine so, how about the tb seat, there's no air leaks at all is there ? I had a similar problem with a kawasaki bike i had and it turned out to be a split in one of the inlet rubbers between the carbs and head.

 

[babyboom]

mines is the same, it started a few days ago, i went to work in the morning and noticed the idle was sitting at 1500 when i started the engine

 

[Alienfish360]

Does the GA15 and GA16 throttle bodies suffer the same common issues as the CG Throttle Bodies?

I may try bolting one of them on, and seeing if that sorts it, it may just be another faulty throttle body I've put on

Ok, so I traced it back to the AAC Valve (controls a plunger to allow air to bypass butterfly to adjust engine revs for additional load on the engine)

So I checked the plunger wasn't sticking, and then the haynes says the reading from across 2 - 3 and 3-4 should be between 50-100ohms but mine was reading 114ohms.

I have a few spare so found one, and it was reading 75ohms, so swapped them over, and it's back running sweet again 1500rpm cold idle and 650rpm warm idle, bang on spec.

Just thought I'd post the cure up incase anybody else has similar issues, and decides to use the search

 

[Soixantaine]

This valve, or idle speed control motor, features a rotating circular shutter that can also become clogged up with corrosion. Clean with carb cleaner and a Q-tip, or similar. Gently! It must rotate freely. The one in the photo is a spare I got at a scrapyard. It was so corroded before I cleaned it the shutter would barely move.

S

 

[Alienfish360]

Yeah that's the one, the AAC Valve

Auxilary Air Control Valve

Mine was rotatin freely, the resistance was too high between the pins