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I am in the middle of replacing my 1998 Dodge Dakota 39. V6's timing set.

According to the manual and everywhere online, the camshaft sprocket dot should be at the bottom and the crankshaft sprocket dot should be at the top.

When I turn the engine to line up the existing sprockets in that configuration, the distributor is firing cylinder 4. If I rotate to where the distributor is firing cylinder 1, then the dots don't line up.

Did the last guy turn my distributor shaft 180 or am I misunderstanding these alignments?

If it is something wonky the last guy did, should I "fix" it? My truck has been running rough, but not terrible. I have a bad cat so I assumed that was why.

Pᴀᴜʟsᴛᴇʀ2
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Zach Mierzejewski
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1 Answers1

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As @DaveWinslow was suggesting, I think you are misunderstanding things about ignition timing.

The firing order on your Dakota 3.9 should be 1-6-5-4-3-2. The engine is a 4-stroke (or 4-cycle) engine (Suck; Squeeze; Bang; Blow). When cylinder #1 fires, the crank shaft has to go 720° (two rotations of the crank shaft) before it fires again. This means the #1 piston is at Top Dead Center (TDC) twice for every single time it fires. At the same time #1 is at TDC, so is the #4 piston. When piston #1 is on its compression stroke (just at the time of firing), #4 is at the top of it's exhaust stroke. The opposite holds true as well. When #4 is firing, #1 is at the top of its exhaust stroke.

Your engine is not 180° out ... if you've described everything accurately, it's right where it needs to be.

Pᴀᴜʟsᴛᴇʀ2
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