04/05 owners.. how bad is your CL/OL delay?

Seems like it varies by car... mine is pretty noticeable and reminds me I really need to get EM pretty damn soon.

For those unfamiliar with the issue, the 04+ ECU on a WRX (not sure about STi) has a delay switching to open loop when you nail the gas. End result is you're running lots of boost and around 14.7:1 air fuel ratio for a couple seconds. Obviously this isn't good. I get a stumble around 5K RPM or so which I attribute to this issue.

 

if this is an issue with the ECU, will a reflash fix it?

 

Well, from what I gather Subaru themselves can't offer a fix since it'd muck with emissions requirements... but yes, ECUtek/AP/Utec/whatever should be able to patch it up.

 

can that be fixed with ecutek?

 

sure can buddy, tell your brother to hurry up and get ecutek

 

Before I went with the AP stage 2 mine was very noticeable in 3rd gear. Now it's non-existent.

 

I am getting an AP relatively soon myself (would consider the self-tuning Xede but it looks like it'll be A While before the lowly WRX sees that product), so hopefully I'll have the same experience. Planning on purchasing StreetTuner down the road as well, should allow me to further tweak it if needed.

 

Need a Fix as well

I have a '04 WRX and getting the same delay. SOG suggested an uppipe today. Any thoughts or suggestions?

I hit the gas and experience a delay, then the slow climb begins. I am not as concerned with the turbo lag as I am the delay or unresponsiveness when I hit the gas.

Any good fixes out there? I am all stock

Thanks

 

sounds like you're mistakingly thinking the turbo lag for the ol/cl response. an uppipe isn't going to get rid of the ol/cl delay. it'll lessen turbo lag though.

mine is still slightly noticable at stage 2 but not bad at all

 

Yeah, the uppipe will allow the turbo to spool up quicker... which might actually make the CL/OL delay even more of an issue, ironically.

Merc, here's the quick scoop on the CL/OL:
The Subaru ECU (computer) sits around in Closed Loop waiting for all the stuff to be in place to switch to Open Loop. Closed Loop is for regular driving/cruising and keeps the engine running pretty lean for more efficiently burning fuel. Emissions purposes. Open Loop is used when you stomp on the gas (and also after startup before the oxygen sensor gets warmed up) and gives a richer mixture that will both give you more power and more safety for the motor. The delay, which I gather is also for emissions purposes, causes the ECU to switch to Open Loop a couple seconds after you romp on the gas, so you can find yourself spooling up and making full boost while running the leaner emissions friendly tune. This isn't a good thing since it makes less power and can contribute to detonation and excessive engine wear...

Sure I got some details wrong, but that's the gist of it.

 

Really haven't heard to much about anyone having any problems with the CL/OL delay on the wrx's. I know its a huge problem with the LGT's however, and is one of the main reasons you should get one flashed (if not for the power alone). I have however seen a few bone stock 04 wrx's knock like crazy with the factory mapping (ROMs). However switching out the 04wrx ecu for an 03wrx ecu on the dyno got rid of the knock completly and actually dyno'd 10hp through out the entire power band. I have been diging around in the 04wrx roms for a bit and have noticed that the knock controls and sensetivity have been changed from 03. Causing them to be more knock prone. It may actually be the ecu picking up detonation and pulling timing that is causing the hesitation or kinda stutter you feel.

Doug

Edit: After re-reading your post you are surely not seeing a CL/OL delay above 5k. Most of the delays are only setup to come on under 4krpms.

 

Ol / Cl

Thanks for the feedback and explanations; not u/s the issue has been driving me crazy.

Would reflashing my stock wrx cure the prob and give me a few extra HP?

Or am I better off living with it, etc.

Thanks Again

 

Yup, in this case a reflash would take car of the problem.

Doug

 

Doug,

I didn't mean that the delay happens if I'm at 5k when I stomp on the gas.. just that around 5k is where I get the 'stumble' which is indicative of the switch to open loop (meaning that I'm at full boost from around 3k-5k with a lean map). There's a HUGE nasioc thread about this, and here's a datalog graph from one of the guys there...

Edit: as you can see the A/F ratio doesn't drop until a good bit after boost/rpm build... there's a lot of other people who have seen the exact same thing on stock 04s/05s.

 

And link to thread/logs...

http://forums.nasioc.com/forums/showthread.php?t=671294&page=1&pp=25

 

Ol / Cl

Yep; just checked out the massive thread and at least I am not alone.

It is just not cool that Subaru will not address the issue and that I would have to tap into my own pocket for a fix.

I do want to mod-up but just cat-back and cold air intake. Then maybe some 18s.

Nonetheless, I believe I need to suck-it-up or sell in that it appears many have complained but are getting no action other than hitting their own pockets for a reflash.

It must have been the honeymoon period because I only have 9K miles and have just recently noticed it.

 

Here's a 3rd gear pull from 2500 rpm from the NASIOC discussion...

Looks like 1.5-2 seconds before the A/F ratio drops here.

 

Reflash

Thanks; I had a datalog run in it and it turns out that there is something going on. They suggested making sure the gas was clean and if that did not clear up the issue then to come back for a factory reflash.

On another note, I ran into your old partner at SoG the other day and he said lots of good things about you and your shop.

Thanks again