DB07P1

car has just been into richard at re motorsport as i had a split turbo downpipe and some other bits and bobs needed doing,before it went in i mentioned about a low idle when warmed up,and when i got the car back all seemed fine and dandy however last couple of days it seems to have come back to haunt me,its ok when cold but once fully warmed up if i pull up to a junction and drop the clutch in the revs will drop to nearly 0 and then right itself,hasnt stalled as of yet.
and then when it idles it does it at around 400-600 revs.
any ideas guys?everything else seems to be fine on the car.

DB07P1

DB07P1

anyone?could it be an air leak?

PeeVee

iTrader: (1)

Sounds like a the classic symptoms of a faulty airflow meter

Phil

DB07P1

yea my dad thought it was something to do with the air/fuel mixture because it only happens when u give the car some and then have to slow down a bit quick,it isnt too bad in stationery traffic ie stop/start stuff....which would explain air flow meter being fault i guess.

mikey2

iTrader: (1)

i had a similar problem, well, exactly the same on my mr2 turbo, when i pulled up the revs would drop, and if i gave it some then dropped the clutch the car would stall. It was the D/V leaking. I changed the D/V and it was fine, drove like a whole new car.

scoobian

typically, my car has been idling perfectly, for ever
...until I started reading threads detailing prblems with idle

...tonight, mine wont idle when cold...fine as soon as its warm, but idle just drops to nothing when cold now

DB07P1

im sorry didnt mean to jinx

woody1980

you will be able to rull out the maf if you just disconnect it then try and run the car. if the maf is dead you wont notice any difference. if it was the maf sensor then trust me you would never be able to pull away and do one smooth accelleration. it would judder around like anything. try resetting the ecu and see if that helps.

volcom

i'm all ears for this one...... my car has just started doing this too. I'm totally new to the subaru scene, so haven't got a clue! Mine hasn't stalled yet either but it does make me nervous, idles about 600rpm when warmed up.

woody1980

you have to rule out anything like oil change, coolent change, oil filter, and anything else you might get on a service. then a good old ecu reset normally fixes anything else. ive just done mine cos i came back from a 2 week holiday (had dodge battery bad oil and coolent and filters.) changed the lot and it ran like it was possesed idle was all over the place and struggled to go under 3000rpm. reset the ecu tonight and went for a drive and everything seems to be fine now.

also after fitting front mount intercooler had similar problem due to the huge difference in air intake going from an early very small intercooler to a 2 foot giant thing on the front. idle was like a yoyo for first few days so tried a ecu reset and ran fine again.

volcom

ok... forgive me for asking a really newbie question, where's the ecu and how do i reset it? I'm driving a 2005 WRX, it's been mapped at scoobyclinic before I bought it. Will the ecu reset mess this up?

Told you..... newbie questions!!

woody1980

the ecu is under the passenger footwell. you peal back the carpet to reveal a large steal case with 3 bolts. the ecu is under there. to reset the ecu there are 2 cables hanging under the dash near the steering column. one is black and one is green. these should not be connected and should be easy to find. you connect them both and turn the ignition 2 clicks. you will hear your radiator fan and other things spinning and clicking.

then press the brake then the accelerator half down and hold for 3 seconds then full down, then release. you now start the car and drive for around half a mile.

the check engine light will now flash. IF everything in the car is ok then it will flash on off at a steady pace. you pull over turn engine off and disconnect cables. your done.

if everything is not ok in the car then the check engine light will flash in a morse code type way fast and slow. you can try and write down the code you think it is doing. i dont know off heart but i did search before and found a few websites showing you what the codes mean. basically its stuff like "coolent temp sensor returning 0" or something like that. if you took the car to an garage they could hook the car upto a laptop and tell you all the things that are wrong in one go. BUT as yet my car has never found any faults. you can do a quick search for resetting the ecu but im pretty sure thats it as i did it earlier and it worked ok.

woody1980

i forgot to mention that when you reset the ecu and drive for half a mile you dont use any boost. as in dont accelerate fast and dont go over 3000rpm. just change up slowly and try to drive at say 30 in fourth so find an empty road

volcom

Cheers for that....... I'll be attempting that over the easter weekend, along with my detango mission!

subaruhonky

my 96 sti has a funny idle like this ,doesnt seem to matter wether the car is hot or cold and it doesnt happen all the time.when i come to a stop the revs bounce up and down til they settle,it hasnt stalled yet,but its bloody annoying.i will have to try the ecu reset,but ive read different views on how you do this.some say drive the car steady where others say briskly which way is best

DB07P1

yes i believe i will have a go see what happens!probably blow the car up or suomething
thanks for the info anyway woody

woody1980

it really doesnt make a difference aslong you dont use any boost. basically you want the car to read settings such as air and fuel mixtures and temps and stuff as a standard car ie without turbo. then after that the car knows base readings so when more throttle is applied and boost from turbo the car knows roughly how much it can add. after that it will learn quickly how much to boost from that point onwards.

cars without turbo you must drive how you would normally drive. so you reset ecu then it will learn that this (how your driving at the moment) is your normal driving style so it will adapt to that style. subarus are a bit different and will learn how you drive over a short period.

DB07P1

on my dads bmw 7 series to reset the ecu he had to disconnect the battery for a few minutes then reconnect,and the engine and gear box relearned the driving style from then onwards,does this apply with scoobs or do you have to reset the ecu??

subaruhonky

correct me if im wrong, but from what ive heard you can disconnect the ecu from its power supply and leave it off for a period of time to let its power storage drain off .this should make the ecu forget its previous settings ,but you still need to carry out the resetting procedures that have been mentioned.i havent done it myself yet.polar performance's website explaines the resetting procedure and mentions some of the fault codes that might be thrown up.might be of use

woody1980

yes leaving the power off for ages will mean the maps clear off the ecu. i just had this problem after coming back from a 2 week holiday. can was running really bad and couldnt work out why. just changed oil and coolent and thought i had put wrong oil in or knocked a pipe. just reset the ecu tonight and its running ok again.

woody1980

yes depending on what scoob you have i think but most have the learning ecu which will learn your driving style and adapt slightly

P1 FEK

iTrader: (1)

Have you checked the lambda sensor?

DB07P1

iv been to see richard at re motorsport (subaru specialist) today and it would seem the problem i had was a knackered o2 sensor,which was why my fuel economy was quite bad aswel,hope this helps some people.

volcom

Fair play, how much did that cost you? Just trying to gauge how much damage to my pocket!!

subaruhonky

don't know if this helps but i bought a universal o2 sensor brand new off ebay.it wasn't scooby specific but i dont think that matters you just need to make sure it has the right amount of wires on it.it cost me about £13.00 and looks and fits exactly the same as the one which was already on my car which didnt appear to be a genuine subaru one either! just thought it might be of interest as i'm guessing genuine ones are mega bucks.

DB07P1

wel i needed 1 a few weeks back as i had this problem and he fixed it free of charge because he had a space aftermarket 1,but it didnt last long,soim having to get a subaru 1 which cost £118,at least labour time isnt much

P1 FEK

iTrader: (1)

Bosch Lambda sensors £45

BOSCH UNIVERSAL LAMBDA SENSOR LS 03 on eBay, also, Other Car Parts, Car Parts, Cars, Parts Vehicles (end time 28-Mar-08 08:24:45 GMT)

volcom

nice one guys, thanks for all the advice. i'm going to change over to my recirc valve at the weekend, see if that makes a difference..... then maybe an ecu reset...... and then a new o2 sensor! I'm scottish so parting with cash is the last option

volcom

ok, i'm back..... been searching on lambda sensors as I ain't got a clue what they are! Got a few questions....

1. How easy is this for a DIY job?
2. Where is the lambda sensor? Near the exhaust?

I would have a look myself but it's dark outside now I bought my car with a full Milltek system, complete decat, is the sensor supposed to be screwed into that somewhere?

Feel free to berate me for being so lame with my recent purchase!!