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Hey everyone, I'm hoping someone can help me out on this issue I have with my EJ20 WRX (Hard to tell the year because a previous owner has mixed and matched parts). The car idles very high on a cold start but I have a very temporary fix for this, by giving a couple full throttles before starting the engine. The other issue is that the car has very little performance during the first 10 minutes or so... The exhaust makes a different noise and has very little responsiveness and power. On some occasions, when trying to accelerate out of a usual corner, the engine seems to completely stop, and the car slows down as if I'm using the brakes. When this "stall" or "choke" happens, a fast ticking noise comes from the dash somewhere... I'm not sure what this means.

I was pretty sure the throttle body needed some cleaning to fix this problem but I found out that when the car was serviced about a week ago, they did this and the problem has become a little worse. Anyone know what else could be causing this?

Has the CEL come on? When it was serviced did they check for stored codes?

An easy method to try is to reset the ECU...may do nothing but may help.

The ticking noise is an interesting one...

The check engine light comes on rarely. I don't see it often. The guy who serviced the car said they couldn't check for the codes because the plug in the car has been removed... How do I reset the ECU? Just disconnect the battery?

Tomi wrote:The check engine light comes on rarely. I don't see it often. The guy who serviced the car said they couldn't check for the codes because the plug in the car has been removed... How do I reset the ECU? Just disconnect the battery?

How as the diagnostic plug been removed?? Conversion?

As for the idling issue, check the IACV - Idle Air Control Valve - remove the whole unit without tampering with the solenoid on the top where the wiring plugs in, otherwise you'll be in a whole new world of hurt trying to set that back up properly!

The IACV can become clogged and not operate properly - it's responsible for the sorting out the idle of the engine, if it's not able to operate properly due to extra friction created by crap in there then you're going to have these kinds of issues.

Clean it up, reinstall it and reset the ECU - disconnect the battery and "do the battery dance" - wait about 30 mins. Others also say to press the brake pedal to waste any residual voltage that could be in the system. Once you reconnect the battery start the engine but DO NOT touch the throttle pedal - let the ECU work out it's idle etc, it may bounce up and down for a bit. I give it 5 minutes. Then go for a flogging... er, I mean drive. Some will say to drive it like you stole it for the first drive so the ECU learns all the parametres blah blah... blah. Personally I think this is BS but you can make up your own mind!

Hope this helps, it's the first thing that comes to mind with what you've said here!

Cheers

Bennie

El_Freddo wrote:How as the diagnostic plug been removed?? Conversion?

Don't know how it's been removed but the car has gone though some sort of conversion as the VIN number says it's a 1993 LX!

El_Freddo wrote:As for the idling issue, check the IACV - Idle Air Control Valve - remove the whole unit without tampering with the solenoid on the top where the wiring plugs in, otherwise you'll be in a whole new world of hurt trying to set that back up properly!

Is it easy to remove? Are there any guides or tutorials I can follow to do this correctly?

Tomi wrote:Don't know how it's been removed but the car has gone though some sort of conversion as the VIN number says it's a 1993 LX!

Ah yeah I remember this one now. Conversion and apparently a pretty good one from your accounts on here!

The IACV is relatively easy to do, there is a coolant jacket in it somewhere from memory. There should be a guide somewhere around here that will tell you how to do it. Otherwise Toonga will no doubt dig up something if he reads this

Cheers

Bennie

El_Freddo wrote:Ah yeah I remember this one now. Conversion and apparently a pretty good one from your accounts on here!

The IACV is relatively easy to do, there is a coolant jacket in it somewhere from memory. There should be a guide somewhere around here that will tell you how to do it. Otherwise Toonga will no doubt dig up something if he reads this

Cheers

Bennie

When I get a chance I will have a look and see what I can find.

If RSR555 was around I would suggest you take the car to him.

TOONGA

Sounds a little bit like the temp sensor to me. Running lean when its cold and also not idling up...ECU is probably taking the 10min every morning to readjust its fuel map to suit.... lean to start with....then rich when it gets hot......maybe.....I donno much about WRX's to be honest. Id get a can of CRC and just go over all the plugs going to the engine. Unplug them, squirt some inside both sides and plug it all back in. I had some dramas with moisture in connectors from some of the recent wet mornings. Given that its only a recent thing I wouldn't be surprised if its something similar.

Regards

Doug

NachaLuva wrote:The ticking noise is an interesting one...

I will try and get a recording of it tomorrow morning if it happens.

TOONGA wrote:When I get a chance I will have a look and see what I can find.

Okay thanks

Okay so I recorded the dash this morning and the car "choked" around the 3rd corner. I have uploaded it here, http://www.youtube.com/watch?v=aXo10AF1 ... e=youtu.be . Sorry about the shocking recording, I was holding my phone with one hand while driving. Skip to the 2 minute mark to see the rpm drop as I try to accelerate out the corner. The car also struggled to start up as well. There is this light on the dash that flickers in sync with the ticking noise but I can't for the life of me find it on the internet. I think it may be an outdated temperature light of some sort.

I noticed in the video the same noise happens when you start the car and that light flashes briefly then the car starts (I downloaded the video ) I would think that this is related and could even be a faulty ignition relay. your other issue sounds like a faulty AICV.

It is hard to tell what that light is but if you have access to an owners manual for the 1993 LX it will be listed.

TOONGA

Here is a close up of the light that flickers.
[ATTACH]4131[/ATTACH]

Would I find information on the light in the LX manual or the the STI one? Because the car has an STI dash.

The light looks like cat over temp light, this might be a jdm cluster. I would post this up on RSLC and see what they say, lots of knowledge on conversions and early turbo subi s there. I'd guess ignition relay as well but check out with RSLC chaps.

Tomi wrote:How do I reset the ECU? Just disconnect the battery?

Disconnect the battery.
Press the brakes to turn on the brake lights to discharge any residual power (you can also leave it overnight)
without touching any controls, start the car & leave running (some say till warmed up - fans come on, or for 15min). DO NOT TOUCH ANYTHING during this time.
Turn off

ECU is now reset

Catalytic converter over temperature light. I'll look up how its wired and get back

Can you post some images of the engine and of any sensors in the up-pipe or down pipes?
This will give me an idea of what type of engine and wiring system you have

I found these in his other thread

showthread.php?t=23005







I see it has the easy to replace IACV

here is a video from youtube not quite the same but very descriptive

http://www.youtube.com/watch?v=0WoQxA5q9io

heres one on cleaning the IACV and throttle body

http://www.youtube.com/watch?v=ZMa0nom1iwc

hope this helps

TOONGA

Nice info! Thanks. After I get this done, I should do this afterwards?

NachaLuva wrote:Disconnect the battery.
Press the brakes to turn on the brake lights to discharge any residual power (you can also leave it overnight)
without touching any controls, start the car & leave running (some say till warmed up - fans come on, or for 15min). DO NOT TOUCH ANYTHING during this time.
Turn off

ECU is now reset

Can ya also grab the engine number as well?

The engine is an EJ20 turbo. I couldn't clean the throttle body as I we didn't have any throttle body cleaner. I went over the notes they wrote when they serviced the car a week or so ago. In the notes they said they already cleaned the throttle body. They didn't say anything about the IACV though.