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Old 10-20-2000, 12:08 AM   #1
Keith
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Angry Cold Weather causing the 3-4k hesitation????

DAmn! since its been cooler outside that fuqin hesitation is back! What the hell could that be?? I keep an eye on the o2 sensor and eveything seems to be good 8.5-8.7 all the way through. I have had my ECU replaced with no luck. Any other ideas??
Keith
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Old 10-20-2000, 07:00 AM   #2
gumball
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yeah, my hesitation problem was more pronounced in the cold, I figured on startup the engine was running rougher or louder or something. Or maybe the block is just that much colder and transmits sounds differently (different acoustic signature in frozen aluminum) before it warms up? Talkin' outta my ass of course. The Gary hack fixed all that.
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Old 10-20-2000, 08:41 AM   #3
Sean McElderry
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While I kinda doubt this is the case, it is possible that the stock ECU doesn't add more fuel for cold weather. Is there a intake air temperature sensor for the stock ECU? If there isn't, then it's possible that the ECU isn't compensating for the increased air density so you run lean and are more prone to knock. The knock sensor takes over, retards timing, and voila - you have the hesitation.

Sean
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Old 10-20-2000, 11:53 PM   #4
Fitz
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That makes sense. My car will hesitate beween 3-4K rpms even once heated up. It almost always happens when I punch it getting on the highway or something... An AFC would help with this right??

Thanks,
Fitz
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Old 10-21-2000, 04:40 AM   #5
Keirik
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hey fitz, I don't think an AFC will help with this because keith has one and still has the hesitation.......think his AFC is tuned pretty nicely too
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Old 10-21-2000, 09:05 AM   #6
Rickd
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Now that it is getting pretty close to freezing overnight, I notice sometimes the car just falls flat on it's face when I take off from a stop if I don't get the rev's up high enough. Usually under 2000 rpm though.
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Old 10-22-2000, 11:32 PM   #7
Keith
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the afc is odd. sometimes it works, sometimes it doesn't help. I found that now, its working, but I am sure in about a month or so, its not going to make a difference. This hesitation is an odd problem. I am not sure to add more fuel or take it away. errr...very frustrating. Only get the afc if u have a need for it, not just to help the hesitation. If you were to get anything, get the ITC and advance your timing between 3-4k.
Keith
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Old 10-23-2000, 01:31 AM   #8
Fitz
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Thanks, I'll keep that in mind.

Fitz
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Old 10-23-2000, 05:03 PM   #9
Aaron'z 2.5RS
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Hi all,

I have an interesting take on this.

I too have a MY99 with the hesitation and i read here somewere (sorry i can't remember your name, whom ever you are) One of the guy'z replaced there 99 knock sensor with a 00 or 01 sensor and no more hesitation.

Makes sense

I went to subaru and they want 75 to 85 bucks for one so i haven't done it yet ( i only read the post a day or so ago)

If it's less sensitive than the 99, it makes A LOT of sense.

Just an idea.....SO why dont one of you LESS finacially challanged peeps give it a try and let us know......SHIV maybe, post it in the mag n all...???

AaRoN
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Old 10-24-2000, 06:13 AM   #10
Keith
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hey thats not a bad idea. damn...if I wasnt jobless right now I would go buy one of those. Thanks for that input..I am going to keep that inmind and if I ever get a job again I will post my results Thanks!
Keith
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Old 10-24-2000, 06:53 AM   #11
STiShawn
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Have a Nice Day?

Wow, if its that easy to cure I will find out. I need to go get a fuel filter, so I will buy a 00' knock sensor while Im at it. Check out SUBARUPARTS.com, they're price might be cheaper for the sensor. My 99 has the hesitation occasionally, mostly when its really hot (engine wise) or If its not all the way warm(engine wise). i'll post my findings too.
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Old 10-24-2000, 08:22 AM   #12
Fmdeadrick
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My car has been doing the same thing, for the past 2 weeks or so, they hesitation came back, which had previously gone away with the AFC. I'm also interested in whether the knock sensor will work. I tried tweaking the AFC a bit, to no avail. For a while, I thought it was linked to whether I was running the heater, but even with it off, it still happens, sometimes more pronounced than others. Our weather hasnt been that cold though, maybe only upper 40s at night and 60s in the day. Maybe its a new model year program in the ECU. Time to buy a 2001 right?


mark@kartboy.com
www.kartboy.com
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Old 10-24-2000, 10:30 AM   #13
Revision
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Try resetting your ECU and check the condition of your spark plugs.
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Old 10-24-2000, 07:35 PM   #14
Keith
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I have reset my ECU like 10000000000000 times! (I dont even know how many 0s are in there...thats how many )
and it does fix it for like a day or two. Those are really good days Then it just comes back. Acutally, I have not been having a problem with it latley...thats good..but I think I will when it starts to get really cold. About the plugs, they are new. I have the NGK plugs. Oh well...if it gets bad and I ever get a job again I am going to pick up that knock sensor... thanks
keith
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Old 10-24-2000, 09:28 PM   #15
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I also have a MY99, I had the problem in the middle of the summer so I don't think it is the cold. I do think it was octane related, when I put 87 in it was really bad,then I filled up with high test and the hesitation dissapated.If all of this was coincidence I would be surprised.
Dave
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Old 10-24-2000, 10:08 PM   #16
george
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Guys, I have a MY00 and I also have hesitation problems between 3k-4k RPMs. I'd think twice before buying a $75 sensor if I really didn't need it.

My 2 cents.

Edit: Also, I live in Miami, FL and I've had those hesitation problems since I got the car (June 2000). So I don't think it's the temperature either.

[This message has been edited by george (edited October 24, 2000).]
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Old 10-24-2000, 10:31 PM   #17
KcImprezzedBoy
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Yeah
I have a MY00 and i have the hesitation BAD right now. Our weather went down about 30 degrees in a week lately and i can definately feel the loss. feels nice to have the surge (from the hesitation going away)around 4k but below that the loss sucks.
I dont think the sensor has anything to do with it.
What is the website for the supposed fix to this problem? I heard there is some magical fixer upper. Anyone had any great/ horrible experiences using this technique?
Andrew Ogden
MY00 Sedona Red Coupe
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Old 10-24-2000, 10:44 PM   #18
Keith
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yeah i think that magical fix thing was something to do with the knock sensor It had something to do with putting a (dont laugh) condom on the sensor or something...dont remember everything. I have not done that yet because I am to much of a bitc* to touch stuff like that
Keith
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