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-   -   Whoa! What Just Happened? (http://www.jeepgarage.org/f5/whoa-what-just-happened-27469.html)

lll2for3lll 08-22-2011 05:38 PM

Whoa! What Just Happened?
 
So I've recently had an issue with my WK misfiring and bucking like crazy. It felt like I was riding a bull.

I solved the issue by replacing the crank sensor that cost $43. Easy repair.

The point I'm getting at is that....my gas milage went from 12 mpg to nearly 14mpg and after I drive it for a while longer, I know I can get in between 14-15 mpg.

Not only did I replace the crank sensor, I reset the PCM as well. (disconnect negative terminal from battery, turn ignition [ON] for about 2 minutes)

^^After doing those 2 things, my WK has been running like a top. Acceleration is through the roof. It's no SRT but it's a lot better than it's ever been. Some say resetting the PCM will boost acceleration but I truly believe that the crank sensor has played a major part in performance because of how well and steady the idling has been. And I've been thinking about having the PCM reflashed because of the lost upgraded software due to the reset but I don't think I will.

I also think that resetting the PCM has allowed it to adjust my acceleration with the 32" tires.

I would advise anybody that has recently mounted larger oversized tires to go out and reset the PCM.

http://i1200.photobucket.com/albums/...k/324d1d60.jpg

robpp 08-22-2011 05:45 PM

Re: Whoa! What Just Happened?
 
what do you mean by RESET?

disconnect neg and then discharge the system?

if so, that is not losing any updates,. its resetting the adaptives.

aslo, the evic is reset too. so you prolly used to get 14-15 and now 12 . thats an average.

since the reset its all new numbers/ and they are 14-15 on the way to 12 the more you beat on it.


do gas mileage witha penand paper and a few gas reciepts; not the evic/

DGoral31 08-22-2011 05:50 PM

Re: Whoa! What Just Happened?
 
Sounds good and all but... im not so sure about how doing this; (disconnect negative terminal from battery, turn ignition [ON] for about 2 minutes)

will help with my over sized tires :confused:

robpp 08-22-2011 05:59 PM

Re: Whoa! What Just Happened?
 
you can turn on ignition. you could turn on headlights. the point is that this completely drains the system so it sort off reboots.

there are all sorts of adaptives that get reset.

it doesnt WIPE out the pcm or lose updates. that is completely WRONG.

and NO it wont help with your oversize tires LOL

lll2for3lll 08-22-2011 06:08 PM

Re: Whoa! What Just Happened?
 
Rob, I reset the MPG on the menu all the time; on long trips, etc.

It's not the first time the thing has been reset.

I know my WK better than anybody else, as far as gas milage and acceleration. The title of this thread is:

"Whoa! What Just Happened?"

And I'm just simply looking for input. The acceleration has gotten A LOT BETTER. Don't believe me? Oh well. I'm enjoying it. :lol:

Something new happened. Something good. And I like it.

And I didn't know I wouldn't lose my software updated after a reboot.

DGoral31 08-22-2011 06:12 PM

Re: Whoa! What Just Happened?
 
lol.... i get it... kind of like a desk top PC... unplugging it and then turning turning the hard switch on to drain any remaining power...

soooooooo whats the point? does re setting the PCM do anything??

viking757 08-22-2011 06:14 PM

Re: Whoa! What Just Happened?
 
Im glad the CKP fixed your issue. Told you not to freak out! :thumbsup:

lll2for3lll 08-22-2011 06:17 PM

Re: Whoa! What Just Happened?
 
Quote:

Originally Posted by DGoral31 (Post 470775)
lol.... i get it... kind of like a desk top PC... unplugging it and then turning turning the hard switch on to drain any remaining power...

soooooooo whats the point? does re setting the PCM do anything??

I don't know for sure but when I first started browsing this forum, I read that it will give a performance bump until it relearn your driving habits.

All I can say is that between the 2, SOMETHING wonderful happened. And I'm enjoying it rather if posters believe it or not.

And yes the gas milage is better. I watch gas usage to a T because I drive the same routes. I make the same moves all the time. I know how much gas I use and when I use it.

lll2for3lll 08-22-2011 06:18 PM

Re: Whoa! What Just Happened?
 
Quote:

Originally Posted by viking757 (Post 470779)
Im glad the CKP fixed your issue. Told you not to freak out! :thumbsup:

It fixed "the" issue and much more. Thanks for that picture of the location of the CKP.

viking757 08-22-2011 07:37 PM

Re: Whoa! What Just Happened?
 
Quote:

Originally Posted by lll2for3lll (Post 470783)
It fixed "the" issue and much more. Thanks for that picture of the location of the CKP.

No problem:D Im glad it fixed it. Also with disconnecting your battery it probably did increase your gas mileage because who knows how long your bad sensor has been and it may have been causing the timing to be slightly off thus killing some performance but not enough to warrant the CEL to come on. Im just speculating but you never know. The "adaptive" technology isn't always that adaptive and giving it a reboot sometimes cant hurt.

lll2for3lll 08-23-2011 10:18 AM

Re: Whoa! What Just Happened?
 
Got up to 17mpg today and no I have no hit the RESET button. I'm just putting along with traffic.

This is amazing. Lol.

robpp 08-23-2011 10:21 AM

Re: Whoa! What Just Happened?
 
just like the Distance to Empty and everything else is wrong in your evic and gas gauge ..... so is the mileage.

get a pen and paper and see your real mileage per tank. BR says so/


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