[Mk2] [NA] 96 rev3 High idle tickover

[Alan135]

my 96 Rev3 when ticking over is idleing very high around 1800
temp of car is about a needle below the half way when warmed up
i have checked air pipes ect but all ok so no sign of any air proplems
any other ides on this ?

[Alan135]

just replaced leads,plugs cap and rotor arm still doing same

any ideas ?

[mikey2]

Is that idling when cold or when warm? if its cold then it should be about 1800 then as it warms up it will settle down to about 850-900. If its still warm and its idling thjat high then it maybe something sticking in the auto choke, you could try stripping the inlet side of things and see if there are any broken bits.

Mike

[EarL]

Notmally, high idle is caused by things like vacuum leaks around the throttle body. Check for leaks on the inlet manifold.

EarL.

[Alan135]

its ideling at 1800 when warm i have checked around the throttle body and no sign of any probs

if the choke was sticking would that make it real hard on the gas ?
car seems to be doing about 50/60 mile to £10 of petrol normal driving

[jeffry-]

Sorry to thread hijack whats the cause of a too low idle , like when starting up first thing instead of idling at say 2000 it idles at 1000 and below.. Also tries to stall when coming to a stop.

[DARRYN]

Could try swapping the water temp sensor (the one for the ecu) if it's not working then the ecu may think the car's cold all the time and be compensating with high revs . Otherwise you could need to clean the isc valve as it may be sticking open .

[Alan135]

Otherwise you could need to clean the isc valve as it may be sticking open .

any info on this how can it be done is it an easy job to do ?

[paul port]

The Idle Control Valve is the off-white thing under the throttle body.
It’s easy to remove once you have the throttle body in your hands – JUST MAKE SURE YOU USE A TIGHT FITTING SCREWDRIVER as the screws can be tight and are made of butter.

Other possible things:
The Rev3 has an ‘Idle up’ solenoid on the rear bulkhead that is switched on when the Aircon pump is running. You can clearly hear this ‘Hiss’ when operating.

The ECU also raises idle speed when there is a high electrical load – EG main beams, rear heater etc, but this should only get you to 1100-1200 rpm.

For 1800, it is most likely to be a significant air leak – check the back of the inlet manifold and anything rubber attached to it – test all hoses for leaks. Though to be honest you should be able to hear any leak of that size.

Final thing…
Throttle position sensor.
There is one pin “IDL” that is a switch contact telling the ECU that the throttle is closed and it should start to control idle with the Idle Control Valve.

Look here (It’s American but still applicable as far as the TPS is concerned)
http://www.mr2-tech.com/bgb/mechanical/ ... system.htm

See Air-Induction, Throttle Body

Paul.

[RobPhoboS]

Old thread I know...but hey, so are our cars !

I'm currently getting a high idle once the car is warm\hot.
I will check for a hose leak tomorrow but if it is the ISCV, what can I clean it with ?

[toxo]

Carb cleaner.

[RobPhoboS]

Cheers.

My one looked clean, gave it a wipe up anyway.

So now I'm thinking perhaps hose leak somewhere?

[black gts]

get some easy start and spray around all inlet and vac control pipes throttle body with the engine running if the revs increase the leak is where you have just sprayed or are spraying.
hope this helps

[RobPhoboS]

get some easy start and spray around all inlet and vac control pipes throttle body with the engine running if the revs increase the leak is where you have just sprayed or are spraying.
hope this helps

Thank you soo much !

I shall try in the morning, I'm fairly sure it's an air leak because something seems odd with the power. And it's not popping and banging like it normally does. (that's my dumb guess)

[RobPhoboS]

Did the spray thing when I started the car, nothing.
Did it after a quick warm up (but the engine hadn't started doing it's hunting yet), and still no rev raise or change.

So will go out until it starts rev-hunting at idle, then see if anything has changed.

[RobPhoboS]

I'm still getting the high rev's at idle once hot.
It does EXACTLY the same thing each time.

Come to a stop, clutch pressed to drop into N, the idle hunts twice, then settles at 1800rpm, after a while it drops to 1200rpm and feels like the air/fuel mix is okish again.

[RobPhoboS]

I cannot hear any air leaks, just wondering if there are some more suggestions please ?

[daveslater3110]

I don't know if you've heard of the paperclip trick mate, but i did it just the other day and it works a treat.

When the car's off, get a paperclip and stick either end of it into the TE1 and E1 holes in the ECU port at the rear right hand side of the engine bay. Then turn the ignition on, (but dont start it!) and the engine light will flash on the dash to tell you if there is any faults.

For example when i did it i had a code 25 which was 2 flashes followed by 5 flashes. But if it flashes continually there is no faults.

If you type mr2 fault codes into google you'll find out what all the codes are..

Hope this helps, Dave.

[RobPhoboS]

Cheers Dave,

I shall go and do that now


(worryingly on the motorway home on Friday I heard some metallic clunks hitting the road - car feels fine, wonder if I hit something or car on the otherside dropped bits! )

[RobPhoboS]

No faults, was continuously flashing.


It hasn't done it this weekend yet, and it's kept dry in underground car park as well, so moisture shouldn't be an issue with it.