HELP! Humidity troubles?
04-11-2011, 09:14 PM
#1
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Year: 1990
Model: Cherokee
Engine: 4.0
HELP! Humidity troubles?
So im thinking my jeep has trouble when its damp outside. its acted up before but snapped out of it. i parked it the other day and it was running just fine, jumped in to go play in the mud the next day after it rained and its a no go. ive done all the at home diagnostics (fuel pressure is good, cps is good, getting 12v to the distributor, rotor is turning, no moisture in the cap) its just not getting fire to the plugs and im fresh out of ideas!!
1990 4.0 auto
1990 4.0 auto
04-11-2011, 10:27 PM
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Year: 1990 Laredo
Model: Cherokee
Engine: 4.0 Inline 6 Renix
How old are your spark plug wires??? are they Cheap ones? Looks for a break in the wires casing.. and are the wires have any rub through they might be grounding out... the water mighyt be acting as a conductor... also I would check the 101 connector on the drivers side...
04-11-2011, 10:40 PM
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Year: 1990 Laredo
Model: Cherokee
Engine: 4.0 Inline 6 Renix
C-101
For once, we aren't talking about Trasborg's pile of Jeepsters. We've hit on this one before in these pages, but it is worth covering again. The '87, '88, and some of the '89 model years had this wonderful connector, called the C-101 connector. It connected all the wiring from the inside of the Jeep to the wiring outside of the Jeep. The problem is, it is over 20 years old and is mounted right at the top of the firewall where all the water cascading off of a newly-opened hood can go. If all that wasn't enough to prove a point, there is a TSB from Jeep way back in '89 that provided a crankshaft sensor bypass kit and instructions to get around the C-101 connector and keep the Jeep running. Most of the '89 models, and all of the '90 models didn't even have the C-101, they just went to a rubber grommet passing the wires through the firewall.
Prevention: You can build a rain shield for it, or just be aware of it when you open the hood. Periodic disassembly, cleaning, dielectric-greasing, and reassembly also help the issues.
Cure: Get rid of it. Solder all the wires from the inside of the Jeep to the corresponding wires from the outside of the Jeep and heatshrink it. All the issues will be gone forever. The risk is if you cross wires just once you can fry stuff pretty easily.
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04-11-2011, 10:43 PM
#8
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Year: 1990
Model: Cherokee
Engine: 4.0
,ime doesnt have one of these, i thought they were only on 87 models. im just completely at a loss with this thing because it was running great th other day. i checked my CPS and it was getting 228 ohms resistance, could it still not be reading the flywheel right? i had a starter bolt work loose while it was parked yesterday and i tightened it and all the other tranny bolts, could that mess anything up?
04-11-2011, 11:06 PM
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Year: 1990 Laredo
Model: Cherokee
Engine: 4.0 Inline 6 Renix
the C101 connector is 87,88 and part of 89.. just a fyi...
Does it crank? and just not fire? and how old is the cap and rotor? they look to be in good shape... You might want to double check your firing order... unless it was running fine before you changed the wires... How old is the cap and rotor? are they Brass? Brass seems to be better for the 4.0... and you have a strong spark coming out of the coil correct?
Does it crank? and just not fire? and how old is the cap and rotor? they look to be in good shape... You might want to double check your firing order... unless it was running fine before you changed the wires... How old is the cap and rotor? are they Brass? Brass seems to be better for the 4.0... and you have a strong spark coming out of the coil correct?
04-11-2011, 11:16 PM
#10
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Year: 1990
Model: Cherokee
Engine: 4.0
it cranks very well, i just bought the jeep in december but the distributor looks fairly new. the firing order is right according to my haynes. gas is getting down to the plugs theres just no spark at the plug. im getting power to the distributor cap but none to the actual plugs so i have no idea whats going on
04-11-2011, 11:19 PM
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Year: 1990 Laredo
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Engine: 4.0 Inline 6 Renix
well if you have power to the cap but not out the cap that only leaves the cap and rotor..... if it is a cheap cap it could be done already... that is why i recomend a brass cap.. do you remeber when you did the wires if it the connector from the cap to the wire was a gold color or a silver color...
04-11-2011, 11:34 PM
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Year: 1990 Laredo
Model: Cherokee
Engine: 4.0 Inline 6 Renix
change over to brass...
check this thread out...
http://www.jeepforum.com/forum/f9/di...uminum-973288/
check this thread out...
http://www.jeepforum.com/forum/f9/di...uminum-973288/
04-12-2011, 06:02 AM
#14
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Year: 1990
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ill definitely change over asap! dad wasnt really aware of what he was saying but when the key is in the RUN position,shouldnt there be way more than just 12v going to the center coil on the dist? just thinking out loud