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88 Renix 4.0 Ignition coil
05-24-2012, 06:53 PM
#16
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
@DFlintstone: I checked for vacuum leaks again and took out my MAP tube, all look perfect, re-torqued my manifold bolts down about a week ago.
@Cruiser: I checked my grounds again, getting a ohm reading of .3 on all sensor grounds so they are all good, I did a resistance reading on the Air temp sensor and its reading as open at both cold and mostly warmed up, am I doing this correctly? Would this cause it to run weird? Running it for about 5 min in an open garage and its definitely running rich
@jacbob: It's been about a week since I set the new sensor, but I believe the input voltage plugged in was 4.93v
@Cruiser: I checked my grounds again, getting a ohm reading of .3 on all sensor grounds so they are all good, I did a resistance reading on the Air temp sensor and its reading as open at both cold and mostly warmed up, am I doing this correctly? Would this cause it to run weird? Running it for about 5 min in an open garage and its definitely running rich
@jacbob: It's been about a week since I set the new sensor, but I believe the input voltage plugged in was 4.93v
05-24-2012, 07:18 PM
#18
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Year: 1988
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I'll try taking it out when I get a chance, wife started going into contractions a few hours ago so I'll try to update as much as I can,
Thanks for everyone's help so far
05-24-2012, 07:20 PM
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05-24-2012, 07:39 PM
#20
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Just do it. What can it hurt? And besides we all might learn something. I only did the ones on my 3 Jeeps cause I had them out to relocate them.
05-24-2012, 08:12 PM
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Year: 90,84
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Well, those pesky electrons. Always doing their own thing. The meter readings are roughly the same. Roughly 1300 at operating temp...but that's with my temp meter in the coolant, not the incoming air.
What id DID notice, before when I unpluged it to check I didn't notice a difference in the engine. After cleaning it the RPM's dropped a tad while measuring. (then went back up when I plugged it back). I would have noticed before. Something did change.
Btw, my first check before warming it up I got zip on the meter, THEN realized I waz on the 2K scale. At let's guess 100* it was up at 2300 ohm's. (in the 200K range)(the meter won't read anything if its out of range)
Mine had orange sealant on the threads. Idk what they used originally. Maybe I'll check mine again in a hotter situation (and check the FSM), before I figure my resistance readings on the Incoming Air Temp sensor on the intake manifold art too low.
Contractions? Warning! You should get a lawyer too!
What id DID notice, before when I unpluged it to check I didn't notice a difference in the engine. After cleaning it the RPM's dropped a tad while measuring. (then went back up when I plugged it back). I would have noticed before. Something did change.
Btw, my first check before warming it up I got zip on the meter, THEN realized I waz on the 2K scale. At let's guess 100* it was up at 2300 ohm's. (in the 200K range)(the meter won't read anything if its out of range)
Mine had orange sealant on the threads. Idk what they used originally. Maybe I'll check mine again in a hotter situation (and check the FSM), before I figure my resistance readings on the Incoming Air Temp sensor on the intake manifold art too low.
Contractions? Warning! You should get a lawyer too!
Last edited by DFlintstone; 05-24-2012 at 08:19 PM.
05-24-2012, 10:20 PM
#22
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I had a few minutes in the garage earlier, went ahead and cleaned mine up, it was pretty dirty. Without starting it up it was reading 3300 on the meter (I had my meter on the wrong scale earlier in the day) and its about 65 in the garage. What I did notice when I started it up for a minute it didn't stink in the garage and I didn't have a huge puddle under the tailpipe
Next time I drive it and get it and get a chance to heat it up, I'll test it again. Hopefully I'll have time to get a reading on the CTS as well.
Next time I drive it and get it and get a chance to heat it up, I'll test it again. Hopefully I'll have time to get a reading on the CTS as well.
05-24-2012, 10:39 PM
#23
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Hey, cool. Maybe I just caught you. Yea, I got 2300 after it had been sitting, not not cool at all. Just was thinking....the 1300 or so I saw could be about right for 100 n' something deg. Granted the air that just rushed in isn't that hot, but the actual deal there is exposed to radiant heat from all directions as well, so it could be say 120*, and be showing 1300 ohms and be right....
05-24-2012, 10:46 PM
#24
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One easy way to get to the 02 sensor near there is to jack up the frame and let the axle hang. Then from the front you have some room. I actually pulled the wheel as well because I was doing other stuff down there as well.
05-27-2012, 01:07 PM
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Update: I've been driving it around for 3 days now and no studdering at all! Completely smooth through all RPM's. I even got 19.5mpg last tank of city driving!
Thanks DFlintstone and cruiser54 for all your help, I never even thought of checking the IAT even though I've looked right at it several times
Thanks DFlintstone and cruiser54 for all your help, I never even thought of checking the IAT even though I've looked right at it several times
05-27-2012, 01:33 PM
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Hey, fantastic! Due to your thread and Cruisers info I may see some gain as well. Got home good and hot yesterday and checked mine before turning it off. Got 1300 again. Then tugging & pushing and fiddling with the wireing it went down to 7-800. right where the IAT wires come out of the sensor, they are not supported. All the flex of the copper happens right there. Just a simple, little dab if silicone there would have protected that from flexing and breaking right where it goes into the sensor.
Great tip on cleaning that Cruiser.
Great tip on cleaning that Cruiser.
Last edited by DFlintstone; 05-27-2012 at 01:36 PM. Reason: Woops! Not the ccv inlet!
05-27-2012, 02:23 PM
#28
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I haven't checked the readings on mine since I cleaned it, its been running too well to mess with it! Were you able to find any replacements? I looked online and I see a lot of other people replacing theirs but I can't seem to find them at autozone, oreilly's, or napa.
05-27-2012, 03:31 PM
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I checked in the FSM for a 2012. It seems to indicate that your daughter is allready there, just a matter of positioning. Did you try jiggling it? 
In the sensor deal on Lungt, it refers to it as the MAT, for manifold air temp, maybe that will help?
In the sensor deal on Lungt, it refers to it as the MAT, for manifold air temp, maybe that will help?
Last edited by DFlintstone; 05-27-2012 at 03:35 PM.
05-27-2012, 07:25 PM
#30
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Year: 1990
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Hey, fantastic! Due to your thread and Cruisers info I may see some gain as well. Got home good and hot yesterday and checked mine before turning it off. Got 1300 again. Then tugging & pushing and fiddling with the wireing it went down to 7-800. right where the IAT wires come out of the sensor, they are not supported. All the flex of the copper happens right there. Just a simple, little dab if silicone there would have protected that from flexing and breaking right where it goes into the sensor.
Great tip on cleaning that Cruiser.
Great tip on cleaning that Cruiser.