What's the right firing order?
#1
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Year: 1999
Model: Cherokee (XJ)
Engine: 4.0
What's the right firing order?
I'm replacing the plugs, wires and distributor cap. I noticed that there is "1" molded into the existing cap. No reason to think it's not original (bought it with 29k miles). The terminal on the cap goes to the #1 cylinder. However, in the Haynes and chilton manual the distributor cap sequence looks rotated by one position. The "1" indicated on the existing dist cap is shown as the number "5" in the manuals. I'm inclined to reinstall the new dist cap in the same order as the one already on the car but confused why both manuals show a different order.
#3
Old fart with a wrench
Look at the location of the #1 wire on the diagram in relation to the hold-down screws. It's the first wire socket past the screw in the clockwise direction. Regardless of it's position on the clock, that molded number 1 has nothing to do with it being the #1 spark plug wire socket. On the old breaker point distributor, you could install the distributor in any position and call #1 wire socket the one that the rotor points to when piston #1 is at TDC on compression. As a matter of fact, on the Chevy small block V8, I used to install the distributor 1 tooth off to give me more room to tighten the hold-down clamp because of the vacuum advance can. Then I just moved the plug wires in the cap. Other guys would look at that and say "That's wrong!" "Yeah, but it runs the 1/4 in 12.5 anyhow!"
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#8
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Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
It's only 1/2 crap Jeff. Can be handy to have print handy. Myself, often I can see the "procedure" described makes no sense, often there are shortcuts. Still a whole lot can be very helpful. Enter the FSM's. (Factory Service Manual) Myself, even on an actual computer, (not a stupid phone), all the info is there but can be a real ***** to find. And that's here in front of a computer, not out at the job. Anyway crusier54.com may, or may not have links to the FSM for your rig.
And thnks for the Credit Turbo.
And thnks for the Credit Turbo.
Last edited by DFlintstone; 12-22-2018 at 09:32 PM.
#9
Old fart with a wrench
Whelp! Wrong again! I should just disappear into a closet, huh? The problem is I haven't had a 4.0L with a dizzy in 8 years and when I changed the cap and wires, I just replaced them where the old ones were. Thanks for setting me straight, Duma. At least when I'm wrong, I'll admit it.
SO, that makes the molded #1 in the right place then, second one past the screw going clockwise, right?
SO, that makes the molded #1 in the right place then, second one past the screw going clockwise, right?
Last edited by dave1123; 12-22-2018 at 09:33 PM.
#10
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Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
I used to install the distributor 1 tooth off to give me more room to tighten the hold-down clamp because of the vacuum advance can. Then I just moved the plug wires in the cap. Other guys would look at that and say "That's wrong!" "Yeah, but it runs the 1/4 in 12.5 anyhow!"
#13
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15 is too young, 36 is too old, 24 is just right. 153624. Credit to an old mechanic friend Mud.
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quititman (04-02-2022)
#14
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Year: 90,84
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Not so sure but it seems to me Pete got a little cared away with his dizy indexing mod. I haven't cut my stuff or tried it on ether of my 90"s, Though.