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Discussion Starter #1
:mad: Please help I have put a non Ho cam in 86 ho motor the 86 motor is currently in my 89 so it is mass air? My question is I have changed the sparkplugs around to the Non Ho firing order but it still runs like crap. Do I have to rewire the fuel injector sequence and if I do does anyone know how or have directions on how to do it this is my first time doing this and its making me crazy:barf:
 

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WESBOB 89 said:
[B My question is I have changed the sparkplugs around to the Non Ho firing order but it still runs like crap. [/B]
This could be numerous possibilties, other than your distributor/firing order issue(which there shouldnt be).
 

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the firing order is off from the injectors..youll need another computer or maybe you could rewire the ingectors..not sure.
 

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Discussion Starter #10
ok guys Im sorry I have an 89 gt with an 86 motor in it. It is a mass air car and the 86 has mass air. I have put an 86 flat tappet non ho cam in it and it runs like crap. It is also running so rich I cant stand by it when its running, my eyes start watering, just trying to figure out whats wrong
 

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Discussion Starter #11
anyone please any input would be appreciated even if u dont know the answer. HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 

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what else do you want to know?

you need a computer from a non-ho engine for a flat tappet cam.
i would assume anyways
 

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one from a t-bird/cougar would probaly work..not sure how diff the wirng is..some of it may have to be swapped over also.
 

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Your cam, distributor and efi injector sequencing all have to match - that is, they need to be the same firing order. So, if you have a non-HO cam (1-5....firing order) you need to re-wire the distributor to that order - start with number 1, the next wire counterclockwise on the dist. top needs to go to number 5, etc. Then, you need to rewire the fuel injectors in the same order. So, the HO firing order is 1-3...... that means that you need to extend the harness so that the plug that is now on the #3 injector can reach the #5 injector instead, etc. If you do that throughout for the wires and injectors, everything should be matched up. Alternatively, if you can get a computer that's compatible with your cam AND mass air, you could swap the computer. But, I don't think they made a non-HO firing order computer that's compatible with a mass air system, but I could be wrong.

Why did you put a non-ho flat tappet cam in? The rollers have SO much more potential, and your roller HO cam would've already matched your dist. and computer. I think the easiest long term solution is to pull that cam and swap back in an HO firing order cam. Have fun.
 

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Discussion Starter #17
My dumb ass friend who said he knew what he was talking about ordered the rebuilt kit now I am the one that suffers.
 

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Discussion Starter #18
thanks guys I rewired it now it runs great When I pulled codes the only one I got was # 11 which means everythangs perfect.
All though it does smell pretty rich could that be cause I have the factory cats with 233,000 miles on them ???
 

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I have found out there is a problem with using a 302 firing order with 5.0 EFI.
Let's say the left O2 reads lean. The computer can adjust each bank seperately, so it richens the left bank. However, 2 of those injectors are now on the right side. Now the right O2 reads rich, so it leans those 4 out. However, 2 of those are now on the left, so the left gets leaner. And so it goes, ping-ponging leaner and leaner and leaner.
The cause of this drove me crazy for months, until someone from a ranger forum clued me in. A Tweecer can be used to tell the computer the new firing order. However I unplugged both O2s and the car is running great on the back up fuel charts.
 
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