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Old 02-08-2013, 11:39 PM
  #23221  
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Originally Posted by greenxj21
Did a compression test today and 2-5 were at 150 while cylinder 1 was at 120. Is this ok?
That number 1 is a little lower than you want to see
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Old 02-08-2013, 11:42 PM
  #23222  
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150 on a high mileage? Did you do it the correct FSM way or the Haynes way?

CYLINDER COMPRESSION PRESSURE TEST

The results of a cylinder compression pressure test can be utilized to diagnose several engine malfunctions.
Ensure the battery is completely charged and the engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed air.
(2) Remove the spark plugs.
(3) Secure the throttle in the wide-open position.
(4) Disable the fuel system. (Refer to Group 14, Fuel System for the correct procedure)
(5) Disconnect the ignition coil.
(6) Insert a compression pressure gauge and rotate the engine with the engine starter motor for three revolutions.
(7) Record the compression pressure on the 3rd revolution. Continue the test for the remaining cylinders

Cylinder Compression Pressure
Ratio...............................8.8:1
Pressure Range............. 827 to1,034 kPa (120 to 150 psi)
Max. Variation Between Cylinders..... 206 kPa (30 psi)
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Old 02-09-2013, 12:54 AM
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Originally Posted by salad
150 on a high mileage? Did you do it the correct FSM way or the Haynes way?

CYLINDER COMPRESSION PRESSURE TEST

The results of a cylinder compression pressure test can be utilized to diagnose several engine malfunctions.
Ensure the battery is completely charged and the engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed air.
(2) Remove the spark plugs.
(3) Secure the throttle in the wide-open position.
(4) Disable the fuel system. (Refer to Group 14, Fuel System for the correct procedure)
(5) Disconnect the ignition coil.
(6) Insert a compression pressure gauge and rotate the engine with the engine starter motor for three revolutions.
(7) Record the compression pressure on the 3rd revolution. Continue the test for the remaining cylinders

Cylinder Compression Pressure
Ratio...............................8.8:1
Pressure Range............. 827 to1,034 kPa (120 to 150 psi)
Max. Variation Between Cylinders..... 206 kPa (30 psi)
Why do you have to unhook fuel system? Here's what I did: hooked up the button to crank the engine to battery terminal positive and the starter motor. Then removed spark plug and tested it (closed throttle, and recorded it on the tutu crank). Also, cylinder 1's spark plug appeared to be a kittles burned (these were all replaced in July with bosch copper plugs). Shoud I redo this test with WOT?
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Old 02-09-2013, 01:15 AM
  #23224  
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Yes wot and disable fuel so it doesn't spray it during the test
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Old 02-09-2013, 09:54 AM
  #23225  
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Still could use some pointers diagnosing my CPS

http://www.jeepforum.com/forum/f11/c...ailing-639123/

I'm going off of the write up in here. When I hook my OHM meter up to the pins indicated Nothing changes. Does this mean I have infinite resistance? I'm new to OHM meters.
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Old 02-09-2013, 10:01 AM
  #23226  
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I was going up a hill last night running about 45 mph and my jeep started to sound like it was skipping. Any suggestions?
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Old 02-09-2013, 10:21 AM
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Originally Posted by luckyunblock
I was going up a hill last night running about 45 mph and my jeep started to sound like it was skipping. Any suggestions?
Was she in 4hi part time??
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Old 02-09-2013, 10:28 AM
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Originally Posted by sycoglitch

Was she in 4hi part time??
No 2wd just daily driving
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Old 02-09-2013, 10:52 AM
  #23229  
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Originally Posted by xj guy
Still could use some pointers diagnosing my CPS

http://www.jeepforum.com/forum/f11/c...ailing-639123/

I'm going off of the write up in here. When I hook my OHM meter up to the pins indicated Nothing changes. Does this mean I have infinite resistance? I'm new to OHM meters.
Yeah a big solid 1 means you have an open. Should have 0 when you tap the leads together directly.
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Old 02-09-2013, 11:22 AM
  #23230  
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Originally Posted by luckyunblock
I was going up a hill last night running about 45 mph and my jeep started to sound like it was skipping. Any suggestions?
Sounding like it was a misfire?
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Old 02-09-2013, 11:25 AM
  #23231  
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Originally Posted by RatchetMaster10
Sounding like it was a misfire?
Check spark plugs and distributer wires,distributer timing. and rotor. if you need to replace one., you my as well replace all. check your injectors too.
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Old 02-09-2013, 12:39 PM
  #23232  
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Popped in a new MOPAR thermostat (only 3x as much as any aftermarket one, but it has the bleeder and came with a gasket) and no more overheating while trying to fill the damn thing, I haven't even put in all the coolant yet and and it idles at 210 all day. Seems letting my jeep sit for a while somehow mysteriously made some parts fail 0_o. Thermostat is one thing I am not going to cheap out on anymore, the one I had in it was maybe a year old. Now off to discount to get some new 30's and emissions on Moday.
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Old 02-09-2013, 01:07 PM
  #23233  
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So i just went bolt up my front clip and support and the holes do not line up with the new radiator. FML. Time to drill I guess.

Edit: Studs aren't even long enough to go through the top support, WTF.

Last edited by avision; 02-09-2013 at 01:10 PM.
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Old 02-09-2013, 01:09 PM
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Originally Posted by avision
So i just went bolt up my front clip and support and the holes do not line up with the new radiator. FML. Time to drill I guess.
I believe you can adjust the mounts on the radiator. I think i had a similar issue on mine.
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Old 02-09-2013, 01:10 PM
  #23235  
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Originally Posted by salad
Yeah a big solid 1 means you have an open. Should have 0 when you tap the leads together directly.
So the CPS I have in shows a 1 when I touch the leads to the pins. Since it is open that means that it is still in good shape correct? Is it possible for the sensor to still be open but to have gone bad?
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