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Unread 12-01-2013, 12:30 AM   #16
kookoo102
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2008 XK Commander 
 
Join Date: Sep 2004
Location: Manassas, VA
Posts: 233
Quote:
Originally Posted by msfulcher77 View Post
Good luck on the trip. Report back your experience. I too am taking a road trip today. Hope all goes well. I've done a lot of work on it recently with little miles put on it... I'm taking tools just in case....

Btw, mixed driving I recently got a little over 14mpg and the city driving was a lot of stop and go. If it's mostly city like that, I'll get around 11, so far... But it's hilly here in the mountains... Kills mileage.

Thanks, same to you as well. Have been trying to stay away from computers and all while on my mini vacation. So.... I have much to update.
XK drove great and provided a pleasant ride for my lil family. my wife and I LOVE the XK over the WJ.
When I attempted to remove the EGR valve, I did replace the "upper" gasket. And I did notice the fasteners on that upper gasket were a little to easy to loosen, made them nice and snug. Will get a new serp belt soon and do the whole thing all over again, but this time change out my EGR valve

All my city driving is all flat.. (NOVA)

While driving on the highway with some traffic (but nothing too crazy) I got just under 272 miles to a tank full. MDS seemed to be a little better. but still a little in and out. Not happy with those MPG... I used to get almost 400 with my 02 / 4.7 WJ with 130k and factory 02 sensors :thumb down:
For the most part it would reach 100 miles by half tank all throughout the trip

Does the 5.7 NEED an EGR valve? Can I do a "block-off"? I have done it on previous toys in the past and am just curious.


Quote:
Originally Posted by 90grandoneer View Post
Have you checked the throttle body/intake manifold plenum cleanliness? If it's real bad (which it probably will be if you haven't), you may also need to change the MAP Sensor. It is one of the primary inputs to the PCM for engine calibration. Also, I would highly recommend you get a catch can for it.
No, I have not removed any of the intake components except for the silencer box and filter box. I remember reading that "cleaning" the TB is not recommended by mopar.. any comments on that?
I am looking to do a catch can soon, and now a MAP sensor too. How much do they go for? And from what I remember reading, they are a PITA to access? I still have to make a trip to jeep to see if I have the newest calibration... I'm sure they will want an ridiculous amount of $$ just for that.

__________________
-2008 - Commander - LTD - 5.7 - QDII - All Options-

2002 WJ-LTD-4.7-QD-2in lift - Gone/ 2002 WJ-Laredo-4.0 Traded - Gone/ 1997 ZJ-LTD-4.0-3.5 inch on 31's - Gone / 1995 ZJ-Larado-4.0 - Gone
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Unread 12-01-2013, 10:17 AM   #17
msfulcher77
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2008 XK Commander 
 
Join Date: Aug 2013
Location: Staunton, VA
Posts: 89
Regarding cleaning TB; my local dealership offers it as a service. I think many people feel that way about not cleaning because it uses the term "non serviceable" which means you can't replace components, but must replace as an assembly. Anyhow, there are a lot of threads on it. I cleaned mine using rubbing alcohol which is recommended by the forum so it doesn't mess things up.

See this thread for MAP sensor. The last post clarifies the right sensor for an 08 Hemi. AZ has the wrong one in their computer. Advance has the right one. Could get at dealer I suppose. There is a plastic tab I had to break off the intake to be able to turn the sensor (ccw 1/4 turn) in order to remove. I just pushed on it with a chisel and it broke right off... It's right next to firewall. I can take an actual pic if you need it.

http://www.jeepforum.com/forum/f67/h...ation-1791137/

I got 18 on the hwy cruising between 60 and 70 depending on speed limit and probably averaged around 68 most of the way. I am using a Superchips tune on Performance 87 running 89 octane. I want to return to stock the next road trip and check to see the difference. The MDS seems to work well but it is harsh when it goes off with the SC tune. It was much smoother on stock. The mileage tune ran like crap around town so I didn't even try it. I'll have to research about that issue.
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Unread 12-01-2013, 06:18 PM   #18
Walt
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2008 WK 
 
Join Date: Oct 2009
Location: Midland, MI
Posts: 1,526
Quote:
Originally Posted by kookoo102 View Post
So just got my XK not too long ago, and did almost all the basic maintenance. (all fluids/filters, plugs, pcv, o2 sensors) think thats all...
Was not till I did all this that I now notice the MDS goes in and out every 2-3 seconds... quite annoying. (on flat level surface)
Been reading on here that the EGR valve could potentailly cause this problem, Would this seem likely? No CEl or anything like that. Is there anything I can do to rule it out? Other then the MDS being annoying, jeep is running great.
Just put in the correct weight oil in, and everything to spec.

If I was to change this out... how in depth of a swap is this? I have no problem doing this, but because of my work schedule, I only have time to do this RIGHT before we leave for NY to visit family.
Thank you
Quote:
Originally Posted by kookoo102 View Post
Also, would anyone say no to getting a EGR valve from Advanced auto? Or is this a "stick with OEM" type of part?

And after an EGR swap, Do I need to do anything for learning purpose? Like disconnect the battery or anything of that nature, or just drive it?
Quote:
Originally Posted by kookoo102 View Post
I have not reset the computer ( you mean unplugging the batt? ) I can give that a try.
I will fill it up with 89 and give that a go tomorrow, heading out for NY right as I get out if work.
I have noticed some things about MDS on my '08 WK HEMI:
  1. MDS is more "squirrely" at the end of oil life than early on. That is, it kicks out more easily and takes longer to kick in than when oil is fresh.
  2. MDS seems to be more consistent on full synthetic 5W-20 oil than is does on 5W-20 dino oil.
  3. MDS functional range is greater when the Heep has been running about 2 hrs (Interstate driving at 70-75 mph).
  4. MDS functional range is greater on 89 octane fuel ("recommended") vs. 87 octane ("minimum required").

EGR valve: Mine went at less than 45K miles. Wierd performance and no DTC's either pending or set. After changeout (with MOPAR part), things settled down. I've been monitoring it since then and found that it is behaving normally. On the highway with low load, it runs about 45-50% open part of the time, then settles in closed at lower loads. You can't block it off as the PCM is expecting some performance changes when it commands it to open. Unexpected results (i.e., no change) will likely set a DTC or MIL. In '08, I read about several members buying EGR gaskets with a smaller hole. It was a metal plate with a smaller hole for ~$20. Many reported getting DTC's or MIL's. I wouldn't bother trying one.
Should be no need to reset the PCM after EGR valve replacement. Mostly, that resets the adaptives (Long Term Fuel Trim & Short Term Fuel Trim). Can't hurt, but does not seem necessary.
BTW: If you have the REN MyGig radio, pull the radio fuse before pulling the negative battery cable. There is a TSB about this....could fry your radio if you do not do it.

Throttle body: If you have not inspected and cleaned the back side of your throttle body and butterfly, that is a positive step. You may be surprised at the difference in crud accumulation between the front and back sides.
Recommend you use care when opening the butterfly....I used a new wooden paint stirrer (cut to about 5" long) and inserted perpendicular once the valve is carefully opened by hand. These are soft wood. I do not disconnect the electrical cable when I clean mine (about every 30K miles).
Recommend you use isopropyl alcohol (or another mild solvent), a clean t-shirt, and q-tips (for around the shaft penetration area). Be very gentle as these are machined surfaces, so you do not want to scratch or otherwise mar them with abrasives. Also, look into the intake manifold with a good flashlight to see if it overly fouled or had puddled oil in it. This would come from the PCV valve.

A Billet Technology Oil Catch Can is a good fix for a generously-sized PCV valve.

Maybe some of these tips will help you on your quest for more acceptable HEMI & MDS performance. CAUTION: This advice may be worth what you paid to get it!
__________________
HEMI CLUB MEMBER #45; SILVER WK CLUB MEMBER #13
'08 WK GC Limited. 5.7L HEMI. Quadra-Trac II. Bright Silver Metallic. Class IV hitch.
Michelin LTX M/S tires. Fumoto oil drain valve. Billet Technology oil catch can.
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Unread 12-06-2013, 01:00 AM   #19
kookoo102
Registered User
2008 XK Commander 
 
Join Date: Sep 2004
Location: Manassas, VA
Posts: 233
Quote:
Originally Posted by Walt View Post
I have noticed some things about MDS on my '08 WK HEMI:
  1. MDS is more "squirrely" at the end of oil life than early on. That is, it kicks out more easily and takes longer to kick in than when oil is fresh.
  2. MDS seems to be more consistent on full synthetic 5W-20 oil than is does on 5W-20 dino oil.
  3. MDS functional range is greater when the Heep has been running about 2 hrs (Interstate driving at 70-75 mph).
  4. MDS functional range is greater on 89 octane fuel ("recommended") vs. 87 octane ("minimum required").

EGR valve: Mine went at less than 45K miles. Wierd performance and no DTC's either pending or set. After changeout (with MOPAR part), things settled down. I've been monitoring it since then and found that it is behaving normally. On the highway with low load, it runs about 45-50% open part of the time, then settles in closed at lower loads. You can't block it off as the PCM is expecting some performance changes when it commands it to open. Unexpected results (i.e., no change) will likely set a DTC or MIL. In '08, I read about several members buying EGR gaskets with a smaller hole. It was a metal plate with a smaller hole for ~$20. Many reported getting DTC's or MIL's. I wouldn't bother trying one.
Should be no need to reset the PCM after EGR valve replacement. Mostly, that resets the adaptives (Long Term Fuel Trim & Short Term Fuel Trim). Can't hurt, but does not seem necessary.
BTW: If you have the REN MyGig radio, pull the radio fuse before pulling the negative battery cable. There is a TSB about this....could fry your radio if you do not do it.

Throttle body: If you have not inspected and cleaned the back side of your throttle body and butterfly, that is a positive step. You may be surprised at the difference in crud accumulation between the front and back sides.
Recommend you use care when opening the butterfly....I used a new wooden paint stirrer (cut to about 5" long) and inserted perpendicular once the valve is carefully opened by hand. These are soft wood. I do not disconnect the electrical cable when I clean mine (about every 30K miles).
Recommend you use isopropyl alcohol (or another mild solvent), a clean t-shirt, and q-tips (for around the shaft penetration area). Be very gentle as these are machined surfaces, so you do not want to scratch or otherwise mar them with abrasives. Also, look into the intake manifold with a good flashlight to see if it overly fouled or had puddled oil in it. This would come from the PCV valve.

A Billet Technology Oil Catch Can is a good fix for a generously-sized PCV valve.

Maybe some of these tips will help you on your quest for more acceptable HEMI & MDS performance. CAUTION: This advice may be worth what you paid to get it!
Thanks for the info
Yet again I will be taking another trip back to NY, so I will be doing another round of work on the XK beforehand. I will be installing a new MAP sensor, cleaning the TB, installing catch can, installing new EGR valve, new upper EGR pipe gasket, and some other little goodies. Oh yea, can't forget to look for exhaust leak #2! For ****s and giggles I will reset the PCM... At this point, why not. can't hurt.

Still debating on getting new tires or not before the trip... probably won't though. damn X-mas gifts:roll eyes:
__________________
-2008 - Commander - LTD - 5.7 - QDII - All Options-

2002 WJ-LTD-4.7-QD-2in lift - Gone/ 2002 WJ-Laredo-4.0 Traded - Gone/ 1997 ZJ-LTD-4.0-3.5 inch on 31's - Gone / 1995 ZJ-Larado-4.0 - Gone
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Unread 12-06-2013, 01:04 AM   #20
kookoo102
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2008 XK Commander 
 
Join Date: Sep 2004
Location: Manassas, VA
Posts: 233
Oh yea.. and the dealer wants $103 to update the calibration... I think it should be free. just me

I guess I will do that some time before the x-mss trip.
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