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Discussion Starter · #1 ·
Hey guys! I just replaced the spark plugs and plug wires in my rodeo today in hopes of curing a miss in the engine. With the truck running, I removed the plug wires from the coils one by one until I realized that cylinder #5 seemed to be the culprit. It was the only one that DIDN'T change the sound or make the motor run even worse. I guess I'm looking at a dead injector, right? Thanx for your help?
 

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I know its probably a bit differnt on that engine but I had a coil pack go bad. Can you verify that all plugs are firing?

-C
 

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Discussion Starter · #3 ·
CSW said:
I know its probably a bit differnt on that engine but I had a coil pack go bad. Can you verify that all plugs are firing?

-C
Yeah! They all Were arcing electricity down to the coil pack mounting bolts! They even shocked me a couple times! Lol!
 

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If a coil went bad you'd have two dead cylinders. You can hear the injectors clicking with a mechanics stethoscope. Don't condemn the injector until you verify it's getting proper voltage.
 

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Does the plug smell like fuel?
 

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Pull the plug and test for spark from the plug. If you have spark, then test for compression, if you have that, then search for a fuel issue.
 

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Discussion Starter · #9 ·
I think I should mention that I have a TINY fuel leak too. Sometimes it drips, sometimes it doesn't. Also, I was laying under the truck with it running and I put my hand on the fuel filter. It was MUCH warmer than other parts around it, and it was, for lack of a better word, "pulsing". You could touch the frame by the pump: no pulsing. Touch the filter: pulsing. And why was it hot? (headscratching!!)
 

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Discussion Starter · #11 ·
5 th rodeo said:
you are just feeling the fuel pump pumping.
That's kinda what I thought but I guess the filter should be changed if it's getting warm.

Being that I've got spark, I guess I should get a compression tester now. Does anyone know if there's a fuse or relay that can be pulled to disable the ignition before testing? AND..if I do, in fact, find low compression in that cylinder, could it be a sticking valve? My truck doesn't emit blue smoke, so I'd say it's probably not the rings. I guess I'd better keep my fingers crossed for a bad injector huh?
 

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CREEPER said:
5 th rodeo said:
you are just feeling the fuel pump pumping.
That's kinda what I thought but I guess the filter should be changed if it's getting warm.

Being that I've got spark, I guess I should get a compression tester now. Does anyone know if there's a fuse or relay that can be pulled to disable the ignition before testing? AND..if I do, in fact, find low compression in that cylinder, could it be a sticking valve? My truck doesn't emit blue smoke, so I'd say it's probably not the rings. I guess I'd better keep my fingers crossed for a bad injector huh?
Do the compression test, on all cylinders. To cancel the coil packs, disconnect the plug that is alone on one side. If its low, pour about 2 oz. of engine oil on the piston, through the plug tube, and test compression again. If compression goes up, you have worn out piston rings.

If it stays the same, try to turn the engine to the compression stroke, where both valves are closed and with the hose from the compression tester, put compressd air, making sure the engine doesnt want to turn (believe me, it will try if its not right.) Them try listening thru the exhaust or the intake. If you hear a hiss, that valve is bad :(

To try the injector on #5, you will need to take the intake plenum out, and then you can access the harness. Try with a test light to see if you are getting any pulse. If its good, then measure the resistance on all the injectors. If theres a diff of more than 10% on #5 them u might have to replace.
Try that before u start throwing parts like in a pit.

Just my 2 cents!!!
 

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Discussion Starter · #14 ·
Just thinking AGAIN....my grandpa used to say that if he had a really internally DIRTY motor, he would drain the oil, disable the ignition, and FILL the motor with kerosene. Then, turn the key, and let the motor spin over for a minute or two, then drain the kerosene. Then, repeat the process until the kerosene drained clean. I've never tried it, but it sounds like it might help free a sticking lifter!
 
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