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'90 Renix Wont start...

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Old 12-24-2011, 09:45 PM
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It figures out #1 from the slots in the flexplate for ignition.

It's not a Cam Position Sensor. It's a stator or sync generator.
Old 12-24-2011, 11:08 PM
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OOOK, Thanks Again. A slot. I wrote that last choppy as usual. So the ECU knows when #1 needs to fire without the sync generator / sync coil.
Old 12-24-2011, 11:47 PM
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Originally Posted by cruiser54
It figures out #1 from the slots in the flexplate for ignition.

It's not a Cam Position Sensor. It's a stator or sync generator.
Love the proper terminology.
Old 12-25-2011, 12:00 AM
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The ECM needs to know cam position to tell #1 from #6, doesn't it?
Old 12-25-2011, 05:51 AM
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Originally Posted by DFlintstone
The ECM needs to know cam position to tell #1 from #6, doesn't it?
ECM could care less about cam position in a Renix. The CPS provides a signal that two pistons are coming up to TDC. The sync generator can tell the ECU if it's #1 by a single slot in the ring inside the dizzy.
Old 12-27-2011, 05:43 AM
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Don, go unplug the wire harness ging into the side of your distributor and see if your Jeep starts, wouldya?

Do it in the name of science.
Old 12-27-2011, 03:02 PM
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****, just got out of the shower. OK.

STARTED! (and didn't get so dirty). I left the plug undone. (4 pins). Got'a run now but later I want to do some "proben". ( I had been was going to do that but I'm dealing with a "brown out", no sun and no water in the creek)

Last edited by DFlintstone; 12-27-2011 at 03:10 PM.
Old 12-27-2011, 03:07 PM
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I didn't need that visual........

But, the New Year is approaching and I know you're due for a shower.

Last edited by cruiser54; 12-27-2011 at 03:56 PM.
Old 12-27-2011, 04:22 PM
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Cruiser is it possible for the cmp sensor to malfunction so that it fires single injectors still but at the wrong time.
Old 12-27-2011, 04:45 PM
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no post from op in a few days now wonder what happened???
Old 12-27-2011, 05:44 PM
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Cruiser is it possible for the cmp sensor to malfunction so that it fires single injectors still but at the wrong time.

I guess it's possible. That's why the factory came up with distributor indexing to solve driveability issues. Go unplug your dizzy and start your Renix 4.0.


no post from op in a few days now wonder what happened???



I'll bet the OP found out what was wrong.
Old 12-27-2011, 05:56 PM
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"""I didn't need that visual........

But, the New Year is approaching and I know you're due for a shower."""

Not gonna mention if that's a little close to the truth! Bet I have more clean junk than you do.

Got the hydro goen at 2A, run the puter at least.

So I started it a few more times passing by. Seems to take 1/2 a second longer. ???What it tries one first, then the other? (6). Without the CMP sensor, (Slick might be looking), The ECU can nail it down with just the CKP sensor. Nice to know, guess it doesn't really matter how.

Started it without the IAC and the TPS last week btw.

Last edited by DFlintstone; 12-27-2011 at 06:07 PM. Reason: wrong quote
Old 12-27-2011, 06:32 PM
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Originally Posted by freegdr
no post from op in a few days now wonder what happened???
Yea, Christmas eve.......

"had to clear the carbon build up to get the new plugs in"

Wonder how much carbon ended up in the cyls. If he has #1 at 5:00 with #1 cyl TDC on compression, with fuel and spark, not flooded, that leaves compression.

How does it sound when you crank it? is it "steady/even" freewheeling?
Old 12-29-2011, 08:54 PM
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Wonder how much carbon ended up in the cyls if his old plugs where the short style.

So Pete, when can I plug my CMP sensor back in? Runs OK but it's starting a little slow.
Old 12-29-2011, 09:00 PM
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Originally Posted by DFlintstone
Wonder how much carbon ended up in the cyls if his old plugs where the short style.

So Pete, when can I plug my CMP sensor back in? Runs OK but it's starting a little slow.
Probably a bit of carbon in that old beast, huh?

I guess I've made my point about stators/sync generators. Honestly, the only time I've ever looked for/found one is with the DRB tester when scanning sensor outputs. Otherwise, a guy would never know.......


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