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Discussion Starter · #1 ·
I recently installed my UTEC, and while I'm very happy with the performance, I've been noticing some detonation when I'm going wide open throttle. I thought at first that this was because I had opened the ABC too far, so I closed it all the way and I was still getting knock. Next I disconected the ABC completely and I'm still having the same problem. Has anyone else had problems with the stock map? I think it may have something to do with the temperature here (about 1F... way too cold... I hate this state) but I'm not completely sure. The local pump stations sell 93 octane, so I don't think that is an issue. Any advice on how I can correct this would be greatly appreciated. I want to be able to drive this car without babying it again.

Thanks,
Josh
 

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Discussion Starter · #2 ·
Well, I managed to find a quick solution to the mess. I just pulled 3 degrees of timing across the board to account for winterized gas and the freaky cold temps here and I'm not getting any more knock. Unfortunately I lost a little power doing this, but I guess I'll just have to wait for the spring autox season to really have some fun again :)
 

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Glad that you found the solution! I've been hearing some murmurings on the boards regarding the WRX and cold-weather knocking... Just be glad that you have the capacity to tune for it! :D
 

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can't you just add a little more fuel under the harder driving conditions? i'm not familiar with the UTEC, but i was under the impression it was very easy to alter fuel maps.

dR
 

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I also have to tune my maps for the cold weather. I pulled 2 degrees of timing from 3000 - 6000. I didn't pull any timing over 6000 because the stage 2 utec map is actually more conservative than the stock map over 6000 RPM.

I also had to add quite a bit of fuel from 3,000 - 7,000 RPM.

I know the UTEC had a feature to compensate for high intake temps, but I don't think it compensates for cold intake temps. I wouldn't be surprised if this was in the next release of the software. As it is now I have 3 maps. I have a map for 0 - 15 degree temps, a map for 16 - 35 degrees, and a map for 35+.

I can't wait until I get my wideband O2 sensor so that I'm not just guessing on fueling requirements like I am now.
 

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I've seen a few threads like this about cold weather knock. I was wondering what kind of intake mods you guys experiencing knock have done. Would it be possible that with a Greddy Airynx or a Rampod type intake that is sucking in mostly warm underhood air that this might help eliminate the problem? Or doesen't the Utec like rampods? Also, would it be possible to just disconnect the Utec in winter and run under the factory ECU or isn't that a good idea with heavy mods done?

I am trying to decide which ECU controler I should go with(Utec, Xede, Yoshio tune) and since I live in upstate NY I would experience the same cold weather knock I'm sure.
 

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Pulling 3 degrees across the entire map is likely unecessary and will lose you a significant amount of output. What you should do is return to the original map, and then record some heavy-load runs using log #1. This will identify for you the EXACT load/rpm combinations (ie. cells) in which you are knocking. I would then pull 1 degree of timing from the offending cells, and all higher load cells at the same RPM point. You will find that your WRX shows three of four RPM regions that are particularly knock prone.

For example; let us suppose that the UTec logs knock at MLP 80 and 3,700RPMs. Pull one degree of timing for the 80, 90, and 100% load columns that correspond to the 3,700 row.

If pulling one degree of timing does not cure all the problem areas, then pull another degree from the cells that are still causing issues, etc. etc. Make small changes and capture 'snapshots' of your map after each change. Use descriptive names and comments for your saved maps.

Note: Cool ambient temps were likely the culprit. TurboXS are rumored to be implementing improved weather compensation mechanisms.

-Pace
 

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Total noob here with aftermarket engine management systems on turbocharged engines. Let me say that first.

If the detonation is cold weather related & can be traced to an air density cause, not poor quality winter gasoline: Why pull timing?

All things remaining equal, fuel quality wise, heat soaking, etc., the detonation is caused by the increased air density leaning out the mixture. It seems counter-intuitive to me to pull timing when in fact the culprit is an increased air/fuel ratio. Why not increase the injection duty cycle during the offending periods if sufficient headroom exists?

Again, I'm a total noob when it comes to utec & the others.

I'm no noob though when it comes to carburetion. & have some experience with Motec V1 & 2, along with Bosch K-jetronic & Motronic on turbocharged vehicles.

What do you guys think? Pace et all... I am very impressed by your breadth & depth of knowledge.

thanks

j.p.


0.9% financing ends 2/28/03. My car won't get here till 3/15/03.. ugh
 

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I believe it's because the IAT (intake air temperature) sensor isn't read by the UTEC currently in a way that will allow for cold-weather modification of the fueling.

In other words, the UTEC knows the motor is knocking - but can't rely on the data (or doesn't even look at the signal) from the IAT sensor so it does what it knows how to do - stop the knocking by reducing ignition advance.

I have heard rumblings that TurboXS is working on the UTEC's ability to incorporate ambient air temperature as one of it's inputs.
 

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is2scooby said:

I have heard rumblings that TurboXS is working on the UTEC's ability to incorporate ambient air temperature as one of it's inputs.
But this will be available thru software update,,or only the new UTEC will come with this?
thanks
tuca
 

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Discussion Starter · #12 ·
Thanks for the advice Pace, I definately noticed a drop in performance after I did this fix and I'll be happy to try something else. I'll be uploading the stage 2 map this weekend (just got the turboxs exhaust and godspeed uppipe :D ) so I'll be needing to retune it anyway. I've already noticed an enormous change in the way the car drives with the work I have done. I can't wait to see what it can do with a properly tuned utec.

Josh
 

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I just got my UTEC today... I have the same knocking PROBLEM.

Im gonna consult with TURBOXS in the morning.

do you guys think colder plugs will help?
 

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Biaxin said:
I just got my UTEC today... I have the same knocking PROBLEM.

Im gonna consult with TURBOXS in the morning.

do you guys think colder plugs will help?
Do you have aftermarket pulleys??
I heard the harmonic dampening of the pulley was causing some UTEC knocking maybe cause the vibration of the pulley would make the knock sensor think it was detonating but it wasnt.
I think i heard this in the board here,i cant find it.
thanks
tuca
Oh,,How i want to get my hands on the UTEC:D :D
 

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He doesn't have colder pullies no. Bring by the UTEC tomorrow Brian and I can pull back timing a bit to compensate. Just take note at what RPM's it is knocking. It's just WAY too cold here I think for that generic map. We'll put the timing back once it warms up.
 

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Hey Dan I have been digging on this cold knock. I gotta get my laptop fixed tomarrow and record a log. The knock occurs all over the place. I just went for quick drive (11:00pm) FREAKING COLD!!! This time it was worse! at the end of 1st, middle of second, most of third, and ect.. the check engine light flashes and You can feel timing being pulled back. Im really glad I got the UTEC. I HAD TO OF BEEN KNOCKING ALL THIS TIME AND NOT EVEN OF KNOWN?

I turned my boost down to .1 and I was getting the same results.

Brad came over to install a strut bar and a boost controller. He brought his laptop, we were driving around in the Dashboard mode.. (REALLY COOL BY THE WAY). and noticed the knock detection.

Then we went in log mode. (It was a little warmer outside at the time) and I was getting knock at 5000-6000 rpm in second, most of third.

I think if we pull back timing across the board that would be safe. but also boring :p

Ill call you in the morning and tell you what TXS says to me.
They might even have a winter map in testing.
 

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Biaxin, I hate you and your car. Even with your timing being pulled due to the knocking, one short ride in your WRX and I'm now pricing out UTEK options and looking into a new turbo for my own. I guess I don't need to landscape this summer or drywall my basement huh?

Thanks again for helping me on the strut tower bar (I have to remember to tighten that down) and on the boost controller. Let me know if you need to use the notebook again this week until you fix yours. Maybe we can pull a log next time to find what cells are having the knock.
 

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Biaxin i envy you:D
You just purchased the UTEC and you are using it already ??cool..
I am waiting for mine and living in Brazil sucks.
I wish i lived in Florida,,more precisely Orlando,,I love Orlando.
I will probably have to wait God to ship to MIAMI(to my cousins house),,so my cousin can send it to me here in Brazil,,he owns a export/import company in MIAMI and he sends me easily and cheap,,but i have to wait 10 days..
Last year he almost convinced me of working in MIAMI in his company with him..but i declined because my girlfriend couldnt go in that time(if she could i would be there),,and i declined too cause i feel a strange feeling in MIAMI(a lot of places all the guys speaks spanish,,they cant even speak correct english),,every year i spend 1 month at orlando and miami(most at orlando),,
Here in Brazil we speak Portuguese from Portugal,,not spanish.
Biaxin - Envy=:D
I want my UTEC
Tuca
 

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Thank you Tuca ! :cool:

Welcome to CLUBWRX.NET Brad ! :D
Im fixing my laptop as we type... Im not gonna eat until I fix this knocking! Its weird, it seems I only get KNOCK when Im at WOT.
It can be any gear / RPM. Im still waiting for TXS to open. Ill let ya guys know.
 
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