Ok, so I hope this doesn’t seem like a stupid question. Take away all logical scenarios and just answer in theory. If a timing chain could jump exactly 180’ would the intake and exhaust valves reverse rolls? Meaning cranking the engine would the cylinder fill by pulling air from the exhaust system? And the exhaust exit thru the intake. I have a vortec engine that for all I can say is properly timed. However the distributor faces the #6 plug wire not #1 when I bring engine to TDC. Verified compression stroke by putting finger in plug hole. The truck ran the day before perfectly, next morning would not start. Added fuel into intake thinking possible fuel pump or vats system, it backfired then. Pulled cap and set to tdc, rotor is at 6. I’m lost guys!

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    Welcome to Motor Vehicle Maintenance & Repair! Are you sure you're looking at the distributor correctly? I mean, the plug wires nor the distributor would have just changed positions overnight unless they were messed with. The timing chain isn't going to give up and swap over 180° ... it just doesn't happen. As far as your question, no, it wouldn't start sucking in off of the exhaust if the timing skipped a full crank rotation. It would be just as you described with the spark being 180° away from the correct cylinder and nothing else. There's just about NO way for this to happen, though. Commented Jun 14, 2020 at 19:23
  • I agree 100%, this just doesn’t happen. I wasn’t the only pair of eyes that seen the rotor position. I pulled the timing cover just to be 100% on the timing being correct. Valve timing is dead on, so I’m back to the distributor as a problem. It’s possible the drive gear or the rotor plate are moving. it’s possible the no start is actually low fuel pressure, I read 52psi, found documents that suggest it needs 60+. However, I introduced fuel directly down the throttle body, and it did not start. I can’t far back to it until Friday, so for now I’m just taking in all the suggestions.
    – Chris
    Commented Jun 15, 2020 at 20:19
  • I'm pretty sure the fuel pressure for your engine should be 43psi when not running and pressurized. Will drop a little when running. I think your next step is to pull the distributor and check out the gear and roll pin (locates the gear to the distributor) to ensure there's no issues there. Commented Jun 15, 2020 at 20:36

1 Answer 1


Has someone put the plug leads on the dizzy wrong?

A classic jape between apprentice car mechanics at tech... if you took more than 30 seconds then you were ribbed as useless... :)

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    This does not provide an answer to the question. To critique or request clarification from an author, leave a comment below their post. - From Review
    – Chenmunka
    Commented Jun 15, 2020 at 16:45
  • @Chenmunka unless you know exactly what is wrong then it still rests a possibility...
    – Solar Mike
    Commented Jun 15, 2020 at 16:50

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