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Unread 10-03-2010, 10:50 PM   #1
newfieZJ
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5.9 , not an issue , but

I just completed a full tune up , MSD coil , wires , champion double platinum plugs , new air filter for the k&n , PCV and a few vacumn lines . I also removed and cleaned the throttle body/parts .

Issue , seems the throttle stays high when I let off the gas , I get no "engine brake" shall I say . Now , I realize it will stay higher when moving , everything I own does , this seems a bit off . If I slip into neutral when cruising 50-60 mph , the idle is over 2k , I hit the gas , it can go higher . Once slowing down with the brake at a stop , the idle is great .

Since the tune , it runs great , not a complaint , and the fuel economy , well , can't mention it , you wouldn't believe me anyways . Don't forget , it's at stock height .

I don't drive the jeep much at all , just spend money on it so my dearest wife can enjoy it apparently , so I have to ask , it this normal ?

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Unread 10-04-2010, 07:02 AM   #2
4Slow9erHybrid
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Quote:
Originally Posted by newfieZJ View Post
I just completed a full tune up , MSD coil , wires , champion double platinum plugs , new air filter for the k&n , PCV and a few vacumn lines . I also removed and cleaned the throttle body/parts .

Issue , seems the throttle stays high when I let off the gas , I get no "engine brake" shall I say . Now , I realize it will stay higher when moving , everything I own does , this seems a bit off . If I slip into neutral when cruising 50-60 mph , the idle is over 2k , I hit the gas , it can go higher . Once slowing down with the brake at a stop , the idle is great .

Since the tune , it runs great , not a complaint , and the fuel economy , well , can't mention it , you wouldn't believe me anyways . Don't forget , it's at stock height .

I don't drive the jeep much at all , just spend money on it so my dearest wife can enjoy it apparently , so I have to ask , it this normal ?

Did you reset the PCM after cleaning the throttle body parts? In particular if you cleaned the IAC plunger, the PCM needs to relearn how to control it. I bet it'll be back to normal once you do it.
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Unread 10-04-2010, 08:57 AM   #3
ADaughen
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The Haynes manual covers how to adjust the IAC if you replace/clean it. If it is too far out or in it will take a minute to adjust and will run high RPMs until it relearn the max/min values of the IAC.

If you don't have the manual I can get you the instructions tonight. It covered adjusting the length of the plunger.
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Unread 10-04-2010, 11:07 AM   #4
89blkcomanche
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i dont know if the 5.9 is programmed this way but most newer motors once put in neutral will stay at or around the rpm speed it was when it was in gear, so when you put it back in gear there is a smother engagement, but i know on my 4.0 it will drop down the idle right away, i would try a ecm reset though, did it do this before the tune up and everything?
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Unread 10-04-2010, 11:09 AM   #5
newfieZJ
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OK , I'll try the PCM resetting first . Hopefully that does the trick . Thanks ADaughen , I have all the factory service manuals , I'll check it out if resetting doesn't work .

My wifes on her way home so , I might disco the battery , and cut the exhaust off , begin my exhaust upgrading , my headers will rust out hanging on the wall

Guthycs , where did you get your purdy clamps ? I don't recall .
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Unread 10-04-2010, 11:16 AM   #6
newfieZJ
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Quote:
Originally Posted by 89blkcomanche View Post
i dont know if the 5.9 is programmed this way but most newer motors once put in neutral will stay at or around the rpm speed it was when it was in gear, so when you put it back in gear there is a smother engagement, but i know on my 4.0 it will drop down the idle right away, i would try a ecm reset though, did it do this before the tune up and everything?
Yeah , I know , but , this is just a little off . It makes the cruise control feel a slight jerky , and when letting off the gas , it just feels like I let up on the gas , but , not completely . Slipping into neutral and hitting the throttle only makes it jump from approx 2000 to almost 3000 RPM until the speed reduces . Everything else is perfect , stopped at idle , no issue . Thanks for replying
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Unread 10-04-2010, 11:17 AM   #7
Virmagicus
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Is the high idle only acting up when in neutral or park? If so it sounds like a vacuum issue/leak to me.
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Unread 10-04-2010, 11:21 AM   #8
newfieZJ
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just when driving at any speed really , most noticable on the hwy doing 50-70mph . Parked it's normal
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Unread 10-04-2010, 08:37 PM   #9
4Slow9erHybrid
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Quote:
Originally Posted by newfieZJ View Post
OK , I'll try the PCM resetting first . Hopefully that does the trick . Thanks ADaughen , I have all the factory service manuals , I'll check it out if resetting doesn't work .

My wifes on her way home so , I might disco the battery , and cut the exhaust off , begin my exhaust upgrading , my headers will rust out hanging on the wall

Guthycs , where did you get your purdy clamps ? I don't recall .
The direct fit cat converter inlet is 2.5", the outlet is 2.25". MOPAC has these band clamps: the 2.5" is an Accuseal exhaust clamp, the 2.25" ones (visible in the picture) are t-bolt clamps (strictly speaking not exhaust clamps, but they work well). I used 2 of them just to be safe.
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Unread 10-04-2010, 09:35 PM   #10
newfieZJ
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Quote:
Originally Posted by guthycs View Post
The direct fit cat converter inlet is 2.5", the outlet is 2.25". MOPAC has these band clamps: the 2.5" is an Accuseal exhaust clamp, the 2.25" ones (visible in the picture) are t-bolt clamps (strictly speaking not exhaust clamps, but they work well). I used 2 of them just to be safe.
thanks for the info . resetting seems to have worked
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Unread 10-04-2010, 10:51 PM   #11
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I was wondering, could you take some pictures, or describe to me what hoses you replaced ? The PCV valve's are the little things that go into the valve cover right ?

I want to do a tune-up to my 5.9 (as i dont know if it ever had one from the previous owner) and you see to know alot about it ive already put in a K&N filter, but i still need to do the wires/plugs and the other stuff, Btw, did you change the distributor cap and rotor ?
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Unread 10-05-2010, 05:51 AM   #12
newfieZJ
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Candyman , why not PM Kolak about his ignition upgrade . It's practically the same except I used a different platimum spark plug . His prices are really good for the kit .

Yes , I did the distributor cap and rotor button too . Unlike Kolak's kit , I couldn't find brass caps which sucked . I think I bought it from NAPA for my Orvis . It's not hard to get at if you remove all the wires first . I just tear them out and , using the #1 on the cap , follow the firing order on the intake for reinstalling . Just remember , the d/side is all odd numbers ,1-3-5-7 and the pass/side is even , 2-4-6-8 from frt to rear

Here's my list and prices (canadian)
MSD coil $45
Accel coil adapter$18
MSD wires $79
Champion double platinum plugs $7ea
Cap and rotor $18
TB gasket$3
Moper CCC $8


I replaced a map sensor hose(which broke when removing the TB , and was rubber) and a few other plastic lines , which I converted to rubber . I'll try to post some pics on here later and a better description . I've replaced the crappy plastic lines on both jeeps now . Under the hood temps will cook plastic lines , make them very brittle and prone to crack IMO . You can't replace the plenum gasket w/o snapping a few off . I always keep a varity of different sizes and some fittings in the tool box . Tight vacumn is important to performance
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Unread 10-05-2010, 08:04 AM   #13
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hey newfieZJ

I should be getting my Kolak Ignition for my 5.9 in the next day or two. Any tips or tricks for getting the spark plugs in and out and accessing the distributor cap and rotor?

Its my first time doing ignition work so anything you can tell me would be helpful.

Thanks
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Unread 10-05-2010, 09:55 AM   #14
newfieZJ
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It's nice to blow out the area around the spark plugs to prevent dirt from entering the combustion chamber . But , if no air , make sure your socket has the rubber washer , pull things out , and reinstall the plugs as straight and slow as you can , guiding them .

An 8" and 3" extention , proper spark plug socket and 3/8 wratchet access every plug with ease .

Always check your gap before installing plugs . Since your going with an MSD coil , you should gap the plugs to 40 thou/.040 instead of .035 stock .

I just pull and toss the old wires to get them out of the way . (Note the #1 on the stock cap , and it's position .)Then the cap can come out through the driver's side . The rotor buttom pulls straight up , sometimes , a little force is needed . Becareful not to smack your hand against the firewall doing this , it hurts lol . Snap the new one on facing the same direction , it only goes on one way . Then feed the cap in as it came out with the #1 as it was stock . starting with your #1 wire , install it to both the plug and the cap using the marked #1 terminal . The firing order is on the intake , follow it clockwise on the cap , attaching wire for wire . My rule of thumb is to use the shortest wire that works to route the wires . The d/side is all odd numbers ,1-3-5-7 and the pass/side is even , 2-4-6-8 from frt to rear .


For the coil , it's a PITA if you don't have the right tools to access the 2 screws holding it on . You basically need the worlds smallest wratchet with a torx head . The battery should be disconnected for this and possibly pulled to access the screws . I have that small wratchet so it saved me some time there .

The accel plug ins are a little tight (adapter), make sure they get snapped in fully . I went so fa as to wrap them in electrical tape .

That should do it

EDIT : Don't forget to check your tire pressure , your going to be driving faster
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