BD5: Idle bouncy

[THUNDA]

have changed idle controll valve

could it be air flow meter problem?

what other things make these cars idle funny?

it jumps between 1500-2000 then check engine light comes on and it drops to 800-1300 and keeps bouncing

car drives mint except for this

cheers

[Guest]

SOOOOoooooo the check engine light comes on...

SOOOooooo you should be able to get a code. That would help, in saying that even if the code says something like for example o2 sensor don’t mean it’s the o2, a range of things can set the codes to an o2 and other sensors but we can get a general idea o where the problem could be

...Hmm you did say you replaced the idle control valve , why?

[Guest keltik]

Vacuum leak

[THUNDA]

 EGOREX said:

SOOOOoooooo the check engine light comes on...

SOOOooooo you should be able to get a code. That would help, in saying that even if the code says something like for example o2 sensor don’t mean it’s the o2, a range of things can set the codes to an o2 and other sensors but we can get a general idea o where the problem could be

...Hmm you did say you replaced the idle control valve , why?

just because i had a good one in my toolbox from one of my last legacys, bad idle = instantly i thought of idle control valve

[Hailz]

I ran a can of "Subaru Upper engine cleaner" through mine and made quite a bit difference aye as I has a similar problem, no fault codes though. Clean your air flow meter with an appropriate meter cleaner - CRC make one, about $18 from repco, I think it's all the little things that help with this problem, well it did in mine........

[Guest keltik]

Vacuum leak?

[log1call]

Check the codes.

Check for air leaks.

Clean the valve cause it's been sitting in your tool box and is probably full of dirt!

[THUNDA]

no air leaks that i can see, (sooo many vacuum lines on the twin turbo setup)

i think its missing something thought, the round box thingy that i think re-ventalates the air from exhaust? it usually sits next to the abs system on the right and have vacuum lines going to it

my lines have just been joined together, have tried un plugging them and blocking each one, doesnt make even the slightest difference

will check codes shortly, what colour are the diagnostic plugs on this model?

idle controll valve was not dirty at all, was replaced with another one on one of my old subies but turned out it wasnt the fault.

[dubbedup]

Cel 66 ;D

[Guest]

on my 93 was black and green t shaped connectors located under the steering column , post back if you need help doing this, from mem was an arse

[THUNDA]

checked codes, am only getting one code and its 24 - which is idle control valve!!

argggg

wtF?

[Guest]

well, you may aswell whip it off and give it a check/clean, or do that to the one you did take off, and try again.

dont forget to clear the codes aswell

give the wires a good check maby, were the plug is, may have damage or water, just coz youll be in that area anyway, cant hurt to look

-smurff

[THUNDA]

theres not much to clean, its just an electromagnet, has always been clean as its a sealed unit.

checked wiring, all is good, gave a clean wire electronic cleaner and wire brush to connections

how do i clear codes? i can only find green plugs for diagnostic, there are no black plugs ?

[Guest]

you have the type with the browny top and two screws? undoing the screws, removing the unit, clean the spring? and bits in it. it may be jaming?

something like that? i could be way off ???

or do you have the one mounted in the throttle body?

in which case did you clean the slot/hole thing in the throttle body?

-smurff

[THUNDA]

yup i have the one in that pic, there is no spring (or is there?), pretty sure its an electromagnet

yup have taken it off and cleaned, makes no difference

[THUNDA]

i put my sisters afm on my car (same car as mine) and it didnt change anything either

[Guest]

i thought, remembering its been a long time scene i opened one, that there was a spring, maby the spring is in the throttle/idle unit.

so you undid the 2 philips screws lifted out the brown top and gave that a clean, think thats basicly all you can do with those units.

ill have to look when i get home, im intrigued now lol

other than that, you will have to wait for people with a bit more know as to what to test for, ie with a multimeter or Oscilloscope.

-smurff

[THUNDA]

is it worth me resetting the ecu overnight tonight?

[Bazza-NZ]

 THUNDA said:

is it worth me resetting the ecu overnight tonight?

Resetting the ECU does wonders

[gtlegacy]

i have the same idle controller how do you put them back together as i think i bumped mine when i cleaned it and it randomly goes up to 1800rpm when at lights and has a very short idle up/warm up time

[THUNDA]

 Bazza-NZ said:

Resetting the ECU does wonders

will do tonight and leave overnight, unhooking the battery then leaving it does it right?

have some gtb wheels lined up too, pickn them up tomo

[Guest]

http://homepages.ihug.co.nz/~ccgrant/celcheck.htm

you may want to read that, tells you how to reset, think it should work on your car.

lots of times the battery off thing dont do to much

-smurff

[gtlegacy]

join the green and black cel light connectors underdash start car drive over 20kmph i think and the check engine light will flash at even intervals like on off on off evenly if not you still have a problem if it flashes evenly your ecu has been reset stop the car turn the car off and disconnect the green and black plugs

[log1call]

Getting an idle valve code can just mean that the idle valve hasn't been able to keep the idle speed within the range the ecu thinks it should be in. That though could be caused by air leaks, a faulty temp sensor, a faulty neutral switch or adjustment, a faulty throttle position sensor or adjustment, the throttle butterfly setting has been changed or the air bypass valve on the throttle body has been changed, there is a low compression on one cylinder etc... Anything that changes the idle speed can cause that code. Defective wiring or electrical faults can also cause them.

If you are sure the valve is clean and all the wiring looks good, have a look at the butterfly adjusting screw and see if the paint on it looks untampered with. Have a look at the air bypass screw on top of the throttle body and see if that looks like it has been tampered with. Check the throttle cable is returning properly and check the throttle position sensor is adjusted properly. The TPS does wear and need adjusting every so often. Use an electrical gauge and check the temperatur sensor readings. Then, and only then......

Have a read in the technical DIY section, maintenance and repair, under the post about how to adjust your idle.

[Guest]

 log1call said:

Getting an idle valve code can just mean that the idle valve hasn't been able to keep the idle speed within the range the ecu thinks it should be in.

Precisely