LS2 120 RWHP loss
10-10-2007, 03:18 PM
#21
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Forget all the stupid calculations, just have your plugs, wires, and coilpacks checked. To check the wires and packs all you really have to to to pull one wire off the plug when the engine is running and hold the end of the wire up to some metal on the motor, you should see the spark arc across the wire and jump to the engine. I would just go ahead and replace the plugs though.
If all the checks ok then do a compression test.
If all the checks ok then do a compression test.
You want me to pull the coil wire off, while the car is running.
Don't you think that the spark is going to jump to whatever ground it can find?
Including me if I am the least path of resistance.
There must be a safer way to check the coil than this method.
10-15-2007, 01:19 PM
#23
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Misfires could be a variety of things: plugs, plug wires, bad coil, clogged injector. These things can be checked by the process of elimination. But a cylinder misfiring can cause your O2's to read a lean condition, then adds more fuel to make the other cylinders too rich, losing even more power.
10-16-2007, 05:37 PM
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Misfires could be a variety of things: plugs, plug wires, bad coil, clogged injector. These things can be checked by the process of elimination. But a cylinder misfiring can cause your O2's to read a lean condition, then adds more fuel to make the other cylinders too rich, losing even more power.
not sure just a thought.
10-18-2007, 11:10 AM
#26
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You can also use a test probe, connected to a ground, and make a small poke through the plug boot to see if the plug is firing or not. If the idle drops and hunts, that plug is firing. If it doesn't change at all, that plug wasn't working in the first place. GL!
10-18-2007, 12:12 PM
#27
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poking holes in boots = not such a great idea. You could always just go to NAPA or advance auto parts, or autozone or wherever and by a 3 dollar spark tester. It just plugs into the end of your boot like a spark plug and then clips onto some ground. You adjust it for the proper gap you want, and crank the car and voila. If it arcs the gap you have spark so the coil/wire combo is good. If it doesnt, change it with a different wire, if still no spark coil and or coil power/ground is bad. If it has spark and that cylinder is misfiring, you have either a fuel injector issue, or a bad spark plug. very simple, very cheap diagnosis without dumb math calculations or just buying new everything until you've spent $200 and still have a damn misfire.
10-21-2007, 01:39 PM
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poking holes in boots = not such a great idea. You could always just go to NAPA or advance auto parts, or autozone or wherever and by a 3 dollar spark tester. It just plugs into the end of your boot like a spark plug and then clips onto some ground. You adjust it for the proper gap you want, and crank the car and voila. If it arcs the gap you have spark so the coil/wire combo is good. If it doesnt, change it with a different wire, if still no spark coil and or coil power/ground is bad. If it has spark and that cylinder is misfiring, you have either a fuel injector issue, or a bad spark plug. very simple, very cheap diagnosis without dumb math calculations or just buying new everything until you've spent $200 and still have a damn misfire.
10-28-2007, 11:50 PM
#29
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Ok so I have changed the spark plugs, tested the spark and did a compression check. The spark plugs are gapped at .040 and the compression was 128 - 135 cross all cylinders. I did find a missing vacuum hose but the car still doesn't pull as hard as it used to. What do I check from here?
Thank
Al
Thank
Al
10-29-2007, 10:16 AM
#30
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well first off, i don't understand how you have all the stuff done to your car but you don't even know how to check for spark.
but anyways why is your gap so small? on all my supercharged cars I ran ~.053
do you have a boost gauge? are you still getting 10 psi??
how about your meth. is it still spraying? if your getting KR you will loose quite a bit of power. I have had grounds go bad where it says I'm spraying but no fluid is coming out.
also when you pulled the plugs, was #6 damaged at all? was the electrode bent or at a different gap from what you set it?
but anyways why is your gap so small? on all my supercharged cars I ran ~.053
do you have a boost gauge? are you still getting 10 psi??
how about your meth. is it still spraying? if your getting KR you will loose quite a bit of power. I have had grounds go bad where it says I'm spraying but no fluid is coming out.
also when you pulled the plugs, was #6 damaged at all? was the electrode bent or at a different gap from what you set it?
10-29-2007, 10:31 AM
#31
<Off topic>
It's funny, I've seen people pull plug wires off the car while running 100 times, but I'm still too ***** to do it.
Maybe Z Angel or some other car chick should post a pic of herself with an arching wire in her hand with a caption, "Just do it, wussy!"
</off topic>
It's funny, I've seen people pull plug wires off the car while running 100 times, but I'm still too ***** to do it.
Maybe Z Angel or some other car chick should post a pic of herself with an arching wire in her hand with a caption, "Just do it, wussy!"
</off topic>
10-29-2007, 02:11 PM
#32
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<Off topic>
It's funny, I've seen people pull plug wires off the car while running 100 times, but I'm still too ***** to do it.
Maybe Z Angel or some other car chick should post a pic of herself with an arching wire in her hand with a caption, "Just do it, wussy!"
</off topic>
It's funny, I've seen people pull plug wires off the car while running 100 times, but I'm still too ***** to do it.
Maybe Z Angel or some other car chick should post a pic of herself with an arching wire in her hand with a caption, "Just do it, wussy!"
</off topic>
You are waaaaay off the topic
10-29-2007, 02:55 PM
#33
Ok so I have changed the spark plugs, tested the spark and did a compression check. The spark plugs are gapped at .040 and the compression was 128 - 135 cross all cylinders. I did find a missing vacuum hose but the car still doesn't pull as hard as it used to. What do I check from here?
Thank
Al
Thank
Al
Good luck to ya...
10-29-2007, 03:05 PM
#34
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The thing that I don't under stand is, it worked just fine before. something has changed but I'm not sure what? Just trying to get some insight on what to look at
thx
Al
10-29-2007, 03:22 PM
#36
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I also found this
https://ls1tech.com/forums/generation-iii-external-engine/443369-what-gap-my-tr55.html
But I'm running 10 PSI boost so I need to go smaller gap.
https://ls1tech.com/forums/generation-iii-external-engine/443369-what-gap-my-tr55.html
But I'm running 10 PSI boost so I need to go smaller gap.
10-29-2007, 07:17 PM
#39
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a o2 sensor does not read fuel. it wiil read the unburnt AIR in the exhaust and correct by trying to add fuel thus making the condition worse. none of that matters anyway cause at WOT it is in open loop not reading the sensors anyway. i would pull the valve covers and check for a broken spring since the ignition and compression are checking out.
