info needed on over-run cutoff valve

[adyh]

You say your electrics are up the swanny ?


Is this part of the same problem im thinking  ?

[Deefadog]

Well i have changed the valve and the same problem occurs, so it's not the valve!, problem disapears when i disconnect the electrical connection to to the over run cut off valve, so it must b the module (I have been told), anything else it could be, maybe something the module tells something else to do with the data from the over run cut off valve is knackered, i don't know??

Any help would be great as I know nothing of this

[adyh]

What i am getting at is it may not be the box behind the dash , it might be the feed to it if you are having electrical problems .

you could change the box out and still have the same problem , because the feed is shagged into it  .


Did the two symptoms occur at roughly the same time  ?

[Deefadog]

Thanks mate

The kangarooing has always been there since i bought the car! also it has a big flat spot between idal and 2500 rpm.

Could be the wiring i guess, but the wiring is sleeved and then sleeved into the main sleeve, if you get what i mean

I want to check it all out but need to know where this module is first so I know where i am going to and from!

what else does this module control, any ideas?

[Deefadog]

bump

[Gambit]

i might be able to help you now mate. i managed to fry my ISV controller of the weekend due to two wires on the throttle switch breaking and mangling the ISV control unit.

so over the weekend i went thru everything with a fine tooth comb and now understand fully how it all works.

1. if you disconnect the ISV only does it drive normally? basically it idles of the idle screw and is usually a bit rough in the mornings till heated up.

2. u can test the throttle switch/bypass valve. operating the throttle by hand and hold it constant above 2krpms. it should hold constant rpm's - no fluxuation

then with your other hand push & hold the little throttle switch closed. u should here the air bypass valve/ diaphram open and the rev's will drop as it tries to drop the plate in the airflow meter. it will then rev back up then drop again, and continue like this for aslong as you keep ur finger on the switch. if its does this then all that is operating correctly.

[Deefadog]

Good timing Gambit, I am off for the week and wanted to test all this anyway

I will try all this tomorrow!

Just a few checks -

1)when disconecting the isv, you mean pull the connector out from it? or disconnct the red wire from the coil?

2) and am i right in saying that I shouold not disconnect the isv when the engine is running, as i think i read that this can damage the isv?

3) The air bypass valve/ diaphram -? is the saucer shaped one that is at the back of the air box?

Cheers again mate!

btw I still can't see you new car from your sig, i get the 'this page can not be found'

[Gambit]

disconnect it from the actual ISV itself. i havent damage mine by disconnecting it when running.

yes air bypass is all them tubes & silver saucer thing at the back of the airbox. you will hear it operate when you work the switch

[Deefadog]

Ok, done the tests (sort of)

with the isv disonnected, my idle was 780 is this ok? it idled ok though

With everything connected except the isv i tried to hold the revs at 2000, but i would not hold, it would raise to 1700rpm and then shoot to 3500rpm on it's own!

I re-did this with the the isv connected, same thing happened

I then disconnected the overun bypass valve connection and the revs went up normally and held at 2000, but once i held the throttle switch closed, the revs shot up to 3500!

Any ideas on this? or more tests? obviously something is very wrong!!!

Cheers

[Gambit]

try just disconnecting the throttle switch and see will it hold the rev's

are you able to test the throttle switch itself??