What is temp sensitive under the hood ?
10-31-2013, 06:40 PM
#31
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I haven't done it. I'd check the MAP feed, ground, and output to the ECU sitting IGN on, and idling warm as suggested above in post #22.
Freedgr was thinking MAP, and mine will sputter and maybe or maybe not start with it unplugged.
About everything under the hood is affected by temperature since basically everything changes size a little. For a year I had a wire that would short when it warmed up. My wires to the lower sensors were mis-routed so that when the heat shield warmed up it would cut into them. A sensor (or wire), that is right near messing up might change when hot/cold. Besides checking the MAP voltages and ground, I'd take a look at, jiggle the gang that comes off the injector harness to the lower sensors. My problem was one of those grounding while the engine was hot.
THEY ARE NO LONGER ROUTED THERE BY THE MANIFOLD
Freedgr was thinking MAP, and mine will sputter and maybe or maybe not start with it unplugged.
About everything under the hood is affected by temperature since basically everything changes size a little. For a year I had a wire that would short when it warmed up. My wires to the lower sensors were mis-routed so that when the heat shield warmed up it would cut into them. A sensor (or wire), that is right near messing up might change when hot/cold. Besides checking the MAP voltages and ground, I'd take a look at, jiggle the gang that comes off the injector harness to the lower sensors. My problem was one of those grounding while the engine was hot.
THEY ARE NO LONGER ROUTED THERE BY THE MANIFOLD
This is how they should be routed.
10-31-2013, 09:00 PM
#32
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Yea, engine temp sensor. (OK Coolant).....I don't trust anything, I don't care who made it. (diagnosing). Anyway just what I posted, a couple of other posters said unplugging it fixed there issue. I remember now, CPTslackass was one of them. IIRC later he figured out it was a wire to it. Maybe mice. Granted it's not so easy to reach but in your case it might be worth a shot, unplugging it to see what happens.
With a Renix, cranking, if you hold the petal to the floor the ECU will cut off fuel. (no injector pulse). This would help it start if it was flooded. You might try that. Lots of air, no fuel........ Running, if you floor it it bypasses most of the sensors and gives it max fuel. (longest injector pulse). I'm not positive there though.
When mine was messing up with that wire grounding I was way pleased to discover it would go like hell if I floored it! I suppose the ECU goes onto "open loop" floored when running, and ignores some sensors.
With a Renix, cranking, if you hold the petal to the floor the ECU will cut off fuel. (no injector pulse). This would help it start if it was flooded. You might try that. Lots of air, no fuel........ Running, if you floor it it bypasses most of the sensors and gives it max fuel. (longest injector pulse). I'm not positive there though.
When mine was messing up with that wire grounding I was way pleased to discover it would go like hell if I floored it! I suppose the ECU goes onto "open loop" floored when running, and ignores some sensors.
Last edited by DFlintstone; 10-31-2013 at 09:33 PM.
10-31-2013, 09:29 PM
#33
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I just went out and pulled the wires from my MAP and cranked it it. Its warm, not hot. It mostly just cranks but "chugs" a little. Then when I floorboard it, nothing at all it just cranks.
Plugged in the MAP, fires, runs fine.....
Plugged in the MAP, fires, runs fine.....
10-31-2013, 09:30 PM
#34
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10-31-2013, 09:40 PM
#35
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Yea, I wonder of his does the same. His Post #1 describes what we see with the MAP unplugged. Can't help but be curious if his quits "chugging" when he floorboards it.
What do you think of that link with the map test? Yes, we happen to have Jeep IAT's, and no DRBII scanner, but your .02 on that MAP test?
What do you think of that link with the map test? Yes, we happen to have Jeep IAT's, and no DRBII scanner, but your .02 on that MAP test?
Last edited by DFlintstone; 10-31-2013 at 09:42 PM.
10-31-2013, 09:45 PM
#36
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I've always used the DRB for my MAP tests.
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