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87 Renix intke backfire

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Old 06-30-2016 | 05:09 PM
  #16  
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Originally Posted by DFlintstone
Correct me if I'm wrong. On a Renix, with the sync pulse generator unplugged (and ear sawn off)#1 could be anywhere. (like dizzys of old). Different story entirely on post 90 OBD Jeeps.
Wrong.

Read this:

Here’s WHY distributor indexing is so important:

Distributor indexing explained
For clarification though, that’s not a cam sensor inside the Renix dizzy. It’s there to fire the injectors sequentially with the firing order. You’ll never notice if it went bad because the ECU will try to “guess” where it is and does a heck of a job at it.

As for the “timing”, it is controlled by the ECU. Ever notice how wide the tip of the rotor is? Try and wrap your head around this:

When the ECU yells “Fire” to the ignition control module, where is the rotor in relationship to the dizzy terminal? Not to the terminal yet? Past the terminal too far?

What happens to the spark/secondary ignition strength when it has to jump the Grand Canyon in comparison to shooting from a rotor tip?
Old 06-30-2016 | 07:14 PM
  #17  
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Originally Posted by cruiser54
Wrong.
I didn't mean "anywhere" I meant at any position. I'm positive I could go out there right now, index my dizy to fire #1 at 9:00, unplug the insinkrator, (the deal that tells the ECU where the cam is), and she would run fine.
Old 06-30-2016 | 07:31 PM
  #18  
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Originally Posted by DFlintstone
I didn't mean "anywhere" I meant at any position. I'm positive I could go out there right now, index my dizy to fire #1 at 9:00, unplug the insinkrator, (the deal that tells the ECU where the cam is), and she would run fine.
Go do it. I'll wait right here.
Old 06-30-2016 | 07:59 PM
  #19  
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Yer nothing if not predictable! OK you wait right there, I'll get right on it.
You know as well as I it would work just fine. Just a longer crank sometimes with no phase pulse incinkerator.
Old 06-30-2016 | 08:44 PM
  #20  
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Originally Posted by DFlintstone
Yer nothing if not predictable! OK you wait right there, I'll get right on it.
You know as well as I it would work just fine. Just a longer crank sometimes with no phase pulse incinkerator.
Prove it.
Old 07-01-2016 | 11:42 AM
  #21  
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I have not got a chance to index the dist but Ive sat there with it running and tried to play with the rotation. I know i stabbed the dist the correct way even if it was a tooth off i still get no change at all when i try to dial it in. Im going to get a new cap so i can destroy the old one. If this doent work I dont know what to try next.
Old 07-01-2016 | 09:19 PM
  #22  
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I would have checked by now to see if it will rev up spraying starting fluid. Might be your engine temp circuit is telling the ECU to go max lean.

Also you should get that TPS sorted out. Gotta do it anyway, so may as well get that out of the way.
Old 07-02-2016 | 12:26 AM
  #23  
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I have taken the split loom off the entire length from the c101 to the end of the injectors i have seen the 2 factory splices. theres about 8 wires bunched and soldered then theres another coming from the tps and i get an ohm of resistance there but after doing the calcs im supposed to be getting .81 from the tps and the max i can get it is about .55. Its a new tps granted I got for 10 bucks from a Chinese retailer but the old one was exactly the same. Could this be my root problem? Should i run new wires from the tps to the ecm? I know the distributor is an issue but im stabbing correctly and i have tried spinning it slightly both directions. Does the housing need to be in a certain place? I mean if i move the balancer to tds on compression stroke the center spinning node will be correct and i should be able to spin the dist to the correct place to make it right. The center spinning thingamajig is whats really important right? If you get that right the outside should be a matter of spinning it until the thing is good. Im thinking the guy i got it from rebuilt it and couldnt figure this out and thats why the dist ears are cut.
Old 07-02-2016 | 01:10 AM
  #24  
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I'm not convinced your distributor is in correctly.

You must use tips 12 and 13 to get that right. There is no room for error!!!

Too much thinking. Not enough verifying.
Old 07-02-2016 | 07:43 PM
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Ok so i did tips 12 and 13. Ive stabbed this thing about 6 times trying a tooth this way or that. I rotated the distributor so the rotor is just starting to eave the #1 node. im not getting any changes. Im so lost right now on wat my next step is
Old 07-02-2016 | 08:00 PM
  #26  
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Originally Posted by Stephen Cowart
Ok so i did tips 12 and 13. Ive stabbed this thing about 6 times trying a tooth this way or that. I rotated the distributor so the rotor is just starting to eave the #1 node. im not getting any changes. Im so lost right now on wat my next step is
Okay, so you know that is right.
Old 07-02-2016 | 08:00 PM
  #27  
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Unplug the tPS and try starting it.
Old 07-02-2016 | 09:01 PM
  #28  
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I unplugged the tps and it runs the same no matter. Sometimes the intake is super loud from the iac until i move it but then it stopps and no matter how i move the tps it doesnt get loud again.
Old 07-03-2016 | 07:17 AM
  #29  
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I also pulled the fuel rail and turned the key to prime the rail and i use a + and - wire to each injector and they spray a nice mist shaped like a cone.
Old 07-03-2016 | 07:21 AM
  #30  
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I also eleminted the c101 connector. Still trying to figure out how i want to route the splitloom so ill tinker with that and then the tps to see if it helped me get it diald in



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