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Weird Spark Plug Wire Firing Order! Confused!!

13K views 4 replies 3 participants last post by  MyCarIs...  
#1 · (Edited)
Okay, my valve cover on my '98 Camry was leaking oil badly so I replaced the gasket. When I started putting things back together, I forgot to label the spark plug tubes (oh, like no one's EVER done THAT before)! No biggie, I thought--I'll just go to TN.com and look it up. I noticed that a lot of people said the firing order should be 1-3-4-2:

So I tried the 1-3-4-2 approach, to no avail. Even changed out spark plugs, but no luck. After some "wire swapping", my car was able to start using a 4-1-3-2 configuration in the below diagram:


Fire Wall BACK
Top of Valve Cover:
1 2 3 4
Front of Car


Fire Wall
Coil Packs
4 A
1

3 B
2
Front of Car

Now, Question 1: Although I haven't tried it yet, could my car conceivably run using another configuration of wires?

And, Question 2: Could the Coil Packs possibly have been 'swapped' when the previous owner rebuilt the engine (y'know, like where Coil Pack A should've been mounted closest to the FRONT of the car, he might've put Coil Pack B there instead)?

Am I crazy? Or stupid? Or just missing something? My kid (the lil' mathematician of the family) says there are 24 ways to put the spark plug tubes back! I'm not looking forward to that...HELP!
 
#2 ·
Looks like you've got it right.

1) No. swapping any pair of wires will result in two cylinders not running. On a four cyl engine, if it runs at all it'll run very poorly.

2) Don't know if they'll mechanically mount swapped. And I doubt the wiring harnesses are long enough to have them electrically swapped.

Your kid is right, there are mathematically 24 ways to install the plug wires. Although the available wire lengths may not allow some combos.
 
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#3 ·
Well, I guess it's all right then, 'cause I took it for a spin and it ran like it did prior to the work! All I know is my kid's car is 1-3-4-2 and mine is 4-1-3-2, and I'm documenting it in my spreadsheet for future reference!!! Thanks ever so for the quick answer, BMR! Glad I can always count on TN.com!
 
#4 · (Edited)
You car uses a "waste spark" system in there are two coil packs, each of which sparks TWO cylinders with a separate plug wire to each. One cylinder fires, the other is on the exhaust stroke and does not. Next cycle the process is reversed. Thus the two wires from the pack CAN be reversed and still work fine, but No. 4 wire, for example, is too short to reach the other cylinder on that pack. Loss spark lets them get away without a distributor, may wear the plugs faster, but is said to keep the plugs cleaner. It also makes for more exact timing. it's not new, 2 cylinder BMW bikes have used it for over 30 years.
 
#5 ·
Wow, did NOT realize that! I actually was still kinda fumin' about my car bein' such an oddball, but after reading your entry, I'm starting to feel a bit 'cocky' now! Hahahaha! I gotz me a SPESHUL car! Good to know! Thanks, MIB!