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How/Where to adjust the timing? What affects it? What is all the important stuff i need to know?

06 sport
4.0L
Auto
 

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You can't adjust it. It is computer controlled.
 

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You can adjust timing on all vehicles that have a distributor...BUT the reason "Neil F" is saying that you can't is because the vehicle's computer will adjust the timing to compensate for your "mechanical" change in timing. (So, in real terms, you can't adjust your timing to make a positive effect on your performance.) If your vehicle is like my old 1992 YJ, once you adjust your timing more than 3 degrees "plus or minus", the computer shuts down the engine.

If you want to pursue this, I will go into it... but "Neil F." is correct. You won't be able to do it for a performance gain. The computer will compensate for it and make adjustments as if the engine is broke. It will probably "retard" your timing and make your performance worse.

Take care,
 

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You can adjust timing on all vehicles that have a distributor...BUT the reason "Neil F" is saying that you can't is because the vehicle's computer will adjust the timing to compensate for your "mechanical" change in timing. (So, in real terms, you can't adjust your timing to make a positive effect on your performance.) If your vehicle is like my old 1992 YJ, once you adjust your timing more than 3 degrees "plus or minus", the computer shuts down the engine.

If you want to pursue this, I will go into it... but "Neil F." is correct. You won't be able to do it for a performance gain. The computer will compensate for it and make adjustments as if the engine is broke. It will probably "retard" your timing and make your performance worse.

Take care,

First, his '06 has no distributor. Second, you can't adjust the timing on all engines with a distributor.
 

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You can adjust timing on all vehicles that have a distributor...BUT the reason "Neil F" is saying that you can't is because the vehicle's computer will adjust the timing to compensate for your "mechanical" change in timing.
Considering that ignition timing is derived from the flywheel, how do you make the mechanical change?
 

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If you can adjust the distributor, YOU CAN AFFECT THE TIMING. Is that too difficult for your guys to figure out? That adjusts "the timing" of the spark being distributed to the cylinders. Boy what do you guys learn in school? Oh I know, how to be smart asses! You knew what I was saying, but you guys wanted to show how smart you were...

If an engine doesn't have a distributor, then it may be a different story. But all engines have a way to adjust the timing... either mechanical or electronically. Now, it is true that the later engine's computer system will work against this "intrusion" and generally make your vehicle run worse. Generally it will "adjust" your "adjustment" (if you can make it) by retarding the timing.

So again, ALL ENGINES THAT HAVE A DISTRIBUTOR CAN HAVE THEIR TIMING ADJUSTED. Whether it will make a positive performance gain on your engine is up to your computer.

Take care and have a great Christmas!!!
 

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If you can adjust the distributor, YOU CAN AFFECT THE TIMING. Is that too difficult for your guys to figure out? That adjusts "the timing" of the spark being distributed to the cylinders. Boy what do you guys learn in school? Oh I know, how to be smart asses! You knew what I was saying, but you guys wanted to show how smart you were...
Considering that the 4.0L engines with distributors have no points or electronic ignition pick-up in the distributor, how does "adjusting" the distributor affect the ignition timing? (The sync signal generator in the distributor affects injection timing, but has no affect on ignition timing.)

When you rotate the distributor, all you are doing is misaligning the rotor relative to the cap. That has no impact on ignition timing, which is generated by the PCM on the basis of flywheel position as reported by the CPS.

So again, ALL ENGINES THAT HAVE A DISTRIBUTOR CAN HAVE THEIR TIMING ADJUSTED.
That is true. (The PCM adjusts timing on an ongoing basis.) But the distributor has nothing to do with the process.

Is that too difficult for your guys to figure out? That adjusts "the timing" of the spark being distributed to the cylinders. Boy what do you guys learn in school? Oh I know, how to be smart asses!
The guy having difficulty figuring things out would be you. Maybe you did well in school, a long time ago. And you have not figured out that modern engines don't work the same as they did when Eisenhower resided on Pennsylvania Avenue.
 

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By calling a Jeep a modern engine, I think you mean a Jeep engine today is already 10 years behind the times. So, I guess you could say the timing of all jeep motors is already retarded.
 

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If you can adjust the distributor, YOU CAN AFFECT THE TIMING
OK dude, whatever. You're wrong. Hook a scan tool up to a GM Vortec, access the data stream and move the distributor around, and watch the timing......
 

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OK dude, whatever. You're wrong. Hook a scan tool up to a GM Vortec, access the data stream and move the distributor around, and watch the timing......
Yes, you can watch the TJ's timing not change when you rotate the distributor. The TJ's timing is 100% under control of the PCM and moving the distributor will simply cause the PCM to compensate and keep the timing exactly where the PCM wants it to be.

No, rotating the TJ's distributor will not change its timing. Period.

YES rotating the distributor will change an older engine's timing... just not the TJ's.
 

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Yes, you can watch the TJ's timing not change when you rotate the distributor. The TJ's timing is 100% under control of the PCM and moving the distributor will simply cause the PCM to compensate and keep the timing exactly where the PCM wants it to be.

No, rotating the TJ's distributor will not change its timing. Period.

YES rotating the distributor will change an older engine's timing... just not the TJ's.
I haven't messed with the 4.0 yet, but I have plenty of experience with GM Vortecs, and it's the same. On the V8's, you don't even have to index (line up) the rotor when installing the distributor. Just drop it in..
 

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I haven't messed with the 4.0 yet, but I have plenty of experience with GM Vortecs, and it's the same.
If you are still trying to claim the TJ's timing can be adjusted by rotating the distributor, you are wrong. If GM Vortec timing can be adjusted by rotating the distributor, great but the TJ's cannot so they are not the same.
 

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The TJ's timing is 100% under control of the PCM and moving the distributor will simply cause the PCM to compensate and keep the timing exactly where the PCM wants it to be.
There is no "compensation" involved. The PCM does not get ingition timing inputs from the distributor; distributor position has no affect on the PCM-generated ignition timing. Let's not replace one myth with another.
 

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If you are still trying to claim the TJ's timing can be adjusted by rotating the distributor, you are wrong. If GM Vortec timing can be adjusted by rotating the distributor, great but the TJ's cannot so they are not the same.
I never said that. I never claimed that. I'm saying the 4.0 can't be adjusted, like the GM Vortec CAN'T be adjusted. Re-read my posts

I haven't messed with the 4.0 yet, but I have plenty of experience with GM Vortecs, and it's the same.
 

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There is no "compensation" involved. The PCM does not get ingition timing inputs from the distributor; distributor position has no affect on the PCM-generated ignition timing. Let's not replace one myth with another.
I always understood that the 4.0 distributor did affect injector timing, but never knew for sure.
 

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FYI everyone...

The below information was cut and pasted right out of the official Mopar Jeep Factory Service Manual:

"DISTRIBUTOR
All 2.5L 4-cylinder and 4.OL 6-cylinder engines are
equipped with a camshaft driven mechanical distributor
containing a shaft driven distributor rotor.
These distributors are equipped with an internal
camshaft position (fuel sync) sensor (Fig. 2). This
sensor provides fuel injection synchronization and
cylinder identification .
DISTRIBUTOR
ASSEMBLY
TJ
Fig. 2 Distributor and Camshaft Position Sensor
(Typical Sensor Shown)
The distributors on 2.5L or 4.OL engines do not
have built in centrifugal or vacuum assisted advance.
Base ignition timing and all, timing advance is controlled
by the powertrain control module (PCM).
Because ignition timing is controlled by the PCM,
base ignition timing is not adjustable on any of
these engines.
The distributor is locked in place by a fork with a
slot located on the distributor housing base. The distributor
hold-down clamp bolt passes through this
slot when installed. Because the distributor position
is locked when installed, its rotational position can
not be changed. Do not attempt to modify the distributor
housing to get distributor rotation.
Distributor position will have no effect on ignition
timing.
"
 
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