SamZS

Hi Guys

Got a 55 Blob eye impreza and tonight i drove it for the first time since i got back from the nurburgring last week. Its idling at 1500 rpm which isnt right, it normally idles at 500 or thereabouts ....

There are no lights and it appears to drive fine does anyone have any ideas of the possible problem ?

Many Thanks

Sam

cube320

Sticking idle contol valve?

B0DSKI

iTrader: (17)

Perfectly normal when starting from cold, mine does exactly the same till it's warmed up

jpmilling

hi sam,

i have a 03 blob eye sti and its been doing the same thing. from cold mine starts fine but the revs seems to rise as the car gets warmer but then settles again when driven for a bit. when the car settles it wont go any lower than 1100rpm and when coming to the end of a junction it takes a while for the idle to drop from 2000 to 1100rpm. i took my car to pat when he was at api this week and he alterted it slightly and it is better but still takes a while to settle. (i have a simtek ecu). think im gonna give the idle control a clean at the weekend to see if it solves it.

SamZS

Took it out for a drive this morning to have a better look at the problem, found that when driving without any turbo it was fine and it idled between 500 and 1000 rpm but as soon as i started to drive it harder and use the turbo then the problems started. If you drive it hard up to a junction for example, stop and then put it into neutral the revs will rise up and down as will gill said (between 1000 and 2000 rpm)

I took it to GRD Developments in Chobham and they checked for any air leaks and also changed the maf for me, i took it down the road and it had exactly the same issue. After going back he had a look and noticed i had a different sports cat and thinks there is a possibility its been remapped and suggested i get it onto the rolling road to find out what’s going on

This really isn’t what i need at the moment Any more suggestions

daz1968

iTrader: (13)

I doubt the map would cause this, the idle speed is set in the ecu and it makes adjustments for temperature and other factors, most likely is a sensor is giving an incorrect reading to the ecu and it is compensting based on incorrect info. You have already ruled out the MAF and checked for airleaks, so I would advise getting it checked for error codes, also try disconnecting all sensors and spraying wd40 in the connectors and putting them back on, any poor connection can give running problems, This is what I found with other cars, although I have as yet to problem solve on the Subaru as it has been ok in the two years I have had it. I would check throttle position sensor and idle speed control valve first,

Darren

SamZS

Hi Daz

Thanks for your reply

Do you think its worth me cleaning the idle speed control valve ? Whats the best way to clean this ? Problem with checking for error codes is that it hasnt thrown up the CEL

mmmm

daz1968

iTrader: (13)

if you do a read of codes it will also show a history of old ones so may give a clue i had a cel when i changed fuel pump it cleared but was still able to be read a few weeks later

nullfork

Could be lambda sensor or coolant temperature sensor (or as you know idle valve).

To clean the idle valve, I'd use some carb cleaner; some pics below on where it as and what's inside! It's held on to the throttle body by two small screws...

Stu

SamZS

Thank fella i will give that a go over the weekend

SamZS

Quick question

Which bits am i best off cleaning ? the valve and inside where the valve sits ? and can i use anything other than carb cleaner, bit of a mission trying to get down halfrauds when i dont have a working car

nullfork

I've heard of people using brake cleaner in place of carb cleaner.

Another option is immersing / dipping (the valve) in petrol...

Probably worth pointing out it's a good idea to let it dry out before re-fitting.

You could possibly use a swab dosed in petrol to clean the orifice inside the throttle body too, be careful not to get foreign materials in there though!!

SamZS

I think my throttle body is diffrent to yours because i cant find that on mine ? I took the live off the battery for a while too and poked around all the connectors. Left it for 30 minutes fired it up and now it seems ive got an engine warning light

Maybe that now meens i can get GRD to check it on there laptop

SamZS

And the issue has dissapeared :|

Going to throw it on surrey rolling road in the week and get them to have a quick look to see if they can find anything to be worried about ...

SamZS

Out of intrest :

What should a 55 WRX STI with PPP idle at once warm ? Everything has cleared up for the moment but it seems to be idling under 500 rpm (around 300)

Is this right ?

daz1968

iTrader: (13)

think about 800rpm as that is where my 03 wrx settles to 300 is far to low.

ScoobyDoo69

iTrader: (17)

300 rpm is... very low! Mine sits at around 800 when fully warm mate.

nullfork

My 08 STI idles very low (600rpm) when warm with all the lights / aircon / etc. off...