v4 sti motor, car shakes at idle

[jsan083]

The blow off valve, I\'m not sure if it even works.

[jsan083]

Evowrx - thanks I have message him, hopefully he will be able to check it out.

Marky- thanks for advice will try get subirex to check it

[shore_boy]

 jsan083 said:

Yea he said should get it done next service as its not that bad.

Do you know anyone that could check my plugs and leads? Mechanic cost quite a bit per hour.

As for the ecu, he couldnt connect my ecu onto the scan machine thing.

Thanks shore boy. Do you have a type r as well?

Nope I have a wagon in steel blue. Quite like the extra space and performance loss is very minimal.

You could always try yourself plenty of threads regarding general servicing and tune ups here and on the net. You\'ll even find them specific to your engine.

Unfortunately cheap mechanics don\'t really exist. Everybody likes to think their time is worth as mush as someone elses. Cant blame them, so would I.

[jsan083]

Nope I have a wagon in steel blue. Quite like the extra space and performance loss is very minimal.

You could always try yourself plenty of threads regarding general servicing and tune ups here and on the net. You\'ll even find them specific to your engine.

Unfortunately cheap mechanics don\'t really exist. Everybody likes to think their time is worth as mush as someone elses. Cant blame them, so would I.

True, i never really liked wagons in general but i guess its more practical.

I got it checked out by subirex, he checked plugs, leads, cleaned afm but still a lumpy idle.

Said it was sluggish too when he drove it. Maybe cus bov is not working and not holding air.

Going to get a scan from winger tomorrow hopefully they can pick it up.

[Guest]

Wagon alldae.

Is it worse when cold?

[jsan083]

Haha yea, but i always prefered sedans over wagons and hatchbacks.

Will get the scan done tomorrow which should pick up what needs replacing. Im not sure what downnpipe or cat is lol.

I know it has aftermarket stainless headers though.

[jsan083]

When its cold it fluctuates a bit until it reaches running temp. Then you feel the lumpy idle which makes car shake.

[jsan083]

Il have to ask subirex to find out. Yea and it doesnt have that subie rumble cus its got equal something headers

[shore_boy]

Try a new afm as suggested.

Previously I had an R34 Skyline (yes coupe) and it had an issue with power loss in the high rpm range and also it was running rich (over fuelling). I took it to Nissan to have a diagnostic scan done and they didn\'t find anything. I replaced the AFM as per some forum recommendations and never looked back.

Don\'t be scared to go to a reputable wrecker like \'all subaru parts world\' as they provide plug and play warranties and the parts that they do sell are all tested. I\'ve never had an issue with them. Although I could be wrong as we\'re speaking about electrical components and as always nothing beats new (except price).

Also going back to the mechanics suggestion of a chipped/aftermarket ECU is not terrible as I know earlier Possumlink ECU\'s have issued when it comes to idle. Electrical faults are not fun...

Ask subirex if he can post a little something about what he noted on the car. No harm in a second opinion.

[shore_boy]

 evowrx said:

Wagon alldae.

Is it worse when cold?

Yeah buddy. Less attention from the popo too i\'ve noticed.

[Guest]

Scan wont necessarily show any errors. It only shows a fault if its out of its parameters. Check the codes youself with plugs under the dash to save you 50odd.

[shore_boy]

 evowrx said:

Scan wont necessarily show any errors. It only shows a fault if its out of its parameters. Check the codes youself with plugs under the dash to save you 50odd.

This is true, the scan sheet they will give you will show what the ECU is recording. The one I got did not even show safe operational parameters. Also it is not specific by any means. Mine showed things like my throttle position and other irrelevant recordings from sensors.

Although no guarantees that connecting the plugs under the dash will show anything either.

I guess the main question is how much is your time worth and is it worth it to troubleshoot on your own.

[Guest]

If theres codes logged the plugs will show it. Ive had afm issues V5 and replaced it to fix the issue and never threw a code.

[jsan083]

Thanks for responses. I wouldn\'t touch anything on car mechanically as I have little mechanical knowledge.

Will get scan tomorrow and see what happens.

As for a second hand AFM I would need to replace my mushroom pod to factory to keep the warranty valid, which I want to do. I\'m needing a factory intake box to replace the zero sport one I have now.

[Guest]

As for not knowing cars its a great place to start. Theres a how to on the plugs under the dash on here and its easy to do. With ignition off just plug the 2 pin green plugs together and the 1 pin black plug together. Then flick ignition onto 1 click/acc and every relay/electrics in the car will pop/fart/fizz and the CEL will flash with the code.

[Marky]

I still see it as - You know the BOV does not work

Are you sure it\'s not jammed half open?

It\'s a pretty obvious place to start if you know it isn\'t functioning, a leaky BOV will give that poor idle you have every time

Simple test is to block the hose it is plugged in to, and also the vacuum line going to it. You don\'t have to drive it - just see if it sorts the idle out

And has has been said, heaps - the AFM may not even show anything much when being scanned - it would be worth your while asking if there is anyone you can do a quick switchover with to see if it improves the issue. Its a very very common fault with subarus

[jsan083]

Evo wrx- ill leave it to subirex to do, thanks for telling me how to though.

Marky - The mechanic did what you are saying with blocking the hose and unscrewed some bolt on it and used this thing to test if it holds air, in which case it didnt.

And yea if anyone could switch over their AFM it would be nice. I would be keen to try it tonight if someone is willing in auckland

[evljat]

Is it an Orange AFM? You can come and try the one on my car. Located south side.

[jsan083]

I believe so, where in south. Txt me on 0211618059. I would only be avail evening though as I\'m working.

[Subirex Automotive]

plugging in the scanner does not necessarily mean you check for fault codes. i could have done that yesterday when i checked the car by plugging in the connectors. i want the see the live data of the engine sensors. to what i saw yesterday was, the idle being rough intermittently and not lumpy as described. no vaccum leaks were detected after blocking off the bov and its lines, problem was still there. i checked the spark plugs, which was near new, leads were within specs except for number 4 which was showing intermittent values and low reading ( i did replace that ).

cleaned the afm, isc valve as well. did an upper engine clean, was better for a while than it started again. drove it and felt no power from the turbo. car has aftermarket equal length headers, up pipe, vf22 turbo and catless down pipe.

so what i under stand at this stage is that one of the sensors could be a bit lazy and giving a wrong reading. i will be able to confirm this by reading the live data while the fault happens. it can be any sensor related to idling that can cause this rough idle.

will update tomorrow of the findings.

[jsan083]

Thanks subirex for clarifying

[jsan083]

just a quick update, car is better but still bit of rough idle by subirex adjusting idle sensor. will update when idle sensor is replaced.

[evljat]

Any progress with this mate?

[jsan083]

yes, subirex replaced my idle sensor thing and made it much better. and also one lead was replaced too.

may replace, AFM , better BOV, and mushroom pod n future when i got more $$