WRX is hating the cold starts...

Subydoug · Post by **Subydoug** » Sat Jun 01, 2013 9:20 pm

Did you try the ECU reset Tomi?

Regards

Doug

Tomi · Post by **Tomi** » Sat Jun 01, 2013 9:31 pm

I am going to leave the battery disconnected tonight. I also have to leave the car idling for how long tomorrow?

Tomi · Post by **Tomi** » Sun Jun 02, 2013 7:05 pm

Okay so I reset the ECU, well at least I think I did. Is there any way to prove it? I drove the car for a bit afterwards and it seems to drive a little smoother now. Or it could be just a placebo effect

I will test the car on Tuesday morning when I head off to school and see if it idles to 2,300 or not also if that unknown blinking light occurs.

Tomi · Post by **Tomi** » Wed Jun 05, 2013 2:02 pm

Well it seems that the ECU wasn't the problem

The day after I reset it, the car seemed to drive perfectly. 1,700 rpm was the highest it reached when I first started it. But this morning the engine "choked" on me...

YouTube · Post by **El_Freddo** » Sun Jun 09, 2013 12:38 am

I'd still recommend pulling the IACV and cleaning it out - if it's dirty it can effect performance and idle.

Keen to know if there are any stored codes too - could lead to something...

Cheers

Bennie

Tomi · Post by **Tomi** » Sun Jun 09, 2013 2:51 pm

Do I need "Throttle body cleaner" to clean out the IACV? I am also going to clean out the MAF sensor. Is there any way to check for codes even though the diagnostic plug isn't there?

Edit: I just opened up my air filter and took a couple photos of the MAF sensor. Does it look like it needs cleaning?
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[ATTACH]4143[/ATTACH]

Subydoug · Post by **Subydoug** » Sun Jun 09, 2013 4:58 pm

I don't think so mate. All that MAF sensor consists of is that small bit of wire in the middle. The ECU drives current into it to heat it up to a specific temp. As air flows past it cools down, so the ecu supplys more power to maintain the temp. The airflow into the motor is proportional to the current the ecu drives it at. No moving parts to gum up

.

Regards

Doug

Gannon · Post by **Gannon** » Sun Jun 09, 2013 5:53 pm

Subydoug wrote:No moving parts to gum up.

Yes but no.

If the sensor wire gets coated in oil and grime it becomes less responsive because the grime acts as (thermal)insulation and prevents it from measuring the true temperature/current relationship. Over oiled K&N filters are known for causing this

As for the air flow meter in question, it looks quite good.

Tomi · Post by **Tomi** » Sun Jun 09, 2013 6:25 pm

If I take apart the throttle body and IACV I need a new gasket right? Does anyone know where I can get one? The ones on eBay are all the way in the United States!

tambox · Post by **tambox** » Sun Jun 09, 2013 6:50 pm

The air flow (maf) sensors do fail, even after cleaning. The US is the cheapest to get one from. Unplug the air flow sensor and drive with it disconnected, generaly it uses heaps of fuel, but runs ok. This tends to be more noticable in stop/start traffic. If it idles/drives slowly ok all the time, it may not be the MAF. You dont need to "take appart" the IACV, just remove it and check its movemnent. The gasket is is often a "dry" pressed gasket you can carefully re-use.

littlewhiteute · Post by **littlewhiteute** » Tue Jun 11, 2013 6:37 am

Tomi wrote:Do I need "Throttle body cleaner" to clean out the IACV? I am also going to clean out the MAF sensor. Is there any way to check for codes even though the diagnostic plug isn't there?

Edit: I just opened up my air filter and took a couple photos of the MAF sensor. Does it look like it needs cleaning?

Looking inside your MAF, your air filter doesn't do a very good job.

What air filter are you running?

Tomi · Post by **Tomi** » Tue Jun 11, 2013 9:41 pm

tambox wrote:Unplug the air flow sensor and drive with it disconnected, generaly it uses heaps of fuel, but runs ok. This tends to be more noticable in stop/start traffic. If it idles/drives slowly ok all the time, it may not be the MAF.

I will try this tomorrow morning and see if it makes any difference.

littlewhiteute wrote:Looking inside your MAF, your air filter doesn't do a very good job.

What air filter are you running?

A pod filter of some sort. It seems pretty dirty looking with the brown colour. I will take a photo of it tomorrow and try and find a brand on it.

Post by **Alex** » Tue Jun 11, 2013 11:48 pm

Is that a hiclone or something I see in the second pic? Or are those fins something stock?

Post by **TOONGA** » Wed Jun 12, 2013 6:04 am

littlewhiteute wrote:Looking inside your MAF, your air filter doesn't do a very good job.

What air filter are you running?

+1

remove the MAF and clean it with Electrical contact cleaner, then throw away your old air cleaner and get a new one.

Preferably something with a dry reusable filter.

TOONGA

Tomi · Post by **Tomi** » Wed Jun 12, 2013 10:42 am

Tomi wrote:I will try this tomorrow morning and see if it makes any difference.

So I removed the connector going into the MAF sensor and stated the car. As usual the car revved up to about 2,300 for a couple seconds then dropped to about 1,500 and stayed there like it has the last few days. As I tried reversing, I stalled (not because of the engine problem, a common L plater problem). I managed to get on the road, but the car had almost no power. As soon as I got over 2,000 rpm, the car struggled to move. I went around the first corner with no "choke" or hesitation but I pulled over and reconnected the sensor as it was functioning very poorly. The car then worked fine.

Alex wrote:Is that a hiclone or something I see in the second pic? Or are those fins something stock?

I checked Google Images and Hiclone has fins that meet in the center. I don't think my ones are stock however.

littlewhiteute wrote:Looking inside your MAF, your air filter doesn't do a very good job.

What air filter are you running?

Here are a couple photos of it. On the front it says "Cheetah Racing Sports" which I assume is extremely rare because I can't find any on Google

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[ATTACH]4145[/ATTACH]

Subydoug · Post by **Subydoug** » Wed Jun 12, 2013 10:38 pm

Sounds about right with the maf disconnected...running excessively rich and in limp mode(?).

Might be about time to shoot RSR555 a PM and see if he can help you out. He most likely has the tools and spare sensor to troubleshoot with.

Regards

Doug