CC503 Cam Problem...Won't Start
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Your timing is wrong for sure. IMO If you have a 94 opti like you say then did spline it correctly for sure when you installed the opti. How about did you get the opti wet with coolant and it could be that causing misfires that could be popping sounds.
Last edited by SPEED#1; 01-07-2010 at 03:43 PM.
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Three PROBABILITIES:
Spark plug wires incorrectly routed - REALLY EASY to do and happens often.
Lifter preload set too tight causing valve(s) to remain open
Incorrectly installed Opti
Check them in that order since that would be the easiest to the most difficult.
Jake
Spark plug wires incorrectly routed - REALLY EASY to do and happens often.
Lifter preload set too tight causing valve(s) to remain open
Incorrectly installed Opti
Check them in that order since that would be the easiest to the most difficult.
Jake
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valves are loose 4 thread method some may even be less than 4....I have stabbed opti so many times its unreal but I'll give it a go again I'll post a video of what its doing....dont know the quality of the video my buddy recorded it
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first, get the headers sealed up. Thats just stupid. All that un-metered air is probably messing with stuff like the o2's. Then put the air intake back on with the sensors hooked up. The PCM isnt able to meter any air coming in so it wont know what to do. Its not some old school 1960's engine where you can leave a bunch of crap not hooked up.
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first, get the headers sealed up. Thats just stupid. All that un-metered air is probably messing with stuff like the o2's. Then put the air intake back on with the sensors hooked up. The PCM isnt able to meter any air coming in so it wont know what to do. Its not some old school 1960's engine where you can leave a bunch of crap not hooked up.
+1 big time
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first, get the headers sealed up. Thats just stupid. All that un-metered air is probably messing with stuff like the o2's. Then put the air intake back on with the sensors hooked up. The PCM isnt able to meter any air coming in so it wont know what to do. Its not some old school 1960's engine where you can leave a bunch of crap not hooked up.
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sounds like your 180 off on timing. You need to find the compresson cycle of number 1 and make sure the piston is all the way at the top and both valves are closed. Then make sure the rotor is pointing at number 1 on the opti. One way to tell if the rockers are to tight is to find the close possition on the cam. messure from the bottom of the valve spring seat to the top of the valve stem and then back off on the rocker nut and see if there is a change in the hight of the valve stem. If so the rockers are holding the valve open and not allowing it to close. This can be caused by improper seat of a lifter or push rod, wrong pushrod size. If you can dismiss the rockers, lifters and push rods as well as the timimg there should be no reason to tear it down again. Is there a thread on what you have in this engine?
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Yes I have checked the valves and did the 4 thread trick like you said rob...And since when does pressing the pedal Flood **** on a fuel injected Car? not saying it dont just never have had it happen to me before....must be a GM thing....and have since sealed the headers and tried plugging the sensors up but no dice...I have ordered a new opti so we will see how things work out when it gets here
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should start up without the maf or anything hooked up. i got my xfi 292 to start up kinda like the way yours sits
make sure your gear set is lined up on the dots at tdc on # 1 not # 6.
make sure you remembered to put the reluctor wheel back in the timing chain for the crank case sensor to make a connection
cheack all the little **** and dumb **** like injector plugs, and making sure your plug wires are hooked up correctly
IMHO it sounds like its not getting spark. make sure when you put the opti on that it popped on all the way not just half way. my first time changing a cam i THOUGHT it popped onto the dowel but wasnt lined up correctly, and i used the bolts to pull it tight because i had never done it before and needless to say i had issues.
make sure your gear set is lined up on the dots at tdc on # 1 not # 6.
make sure you remembered to put the reluctor wheel back in the timing chain for the crank case sensor to make a connection
cheack all the little **** and dumb **** like injector plugs, and making sure your plug wires are hooked up correctly
IMHO it sounds like its not getting spark. make sure when you put the opti on that it popped on all the way not just half way. my first time changing a cam i THOUGHT it popped onto the dowel but wasnt lined up correctly, and i used the bolts to pull it tight because i had never done it before and needless to say i had issues.
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ironically enough the cam I bought had a broken dowell pin and my 95 has a non vented opti
i tried it at both #1 TDC and #6 TDC (#1 being cam dot was at 12 o'clock and #6 being dot to dot)
at #1 the engine backfires out of the intake and at #6 it backfires out of the exhaust....as far as valve lash I have loosened up the rockers thinking they might be too snug and it still won't crank only backfiring and im lining up the opti's "double pin" to the Double slot on the cam gear and still only backfiring.....I have no clue I have torn this thing apart so much I could do it in my sleep now...some one please shed some light
i tried it at both #1 TDC and #6 TDC (#1 being cam dot was at 12 o'clock and #6 being dot to dot)
at #1 the engine backfires out of the intake and at #6 it backfires out of the exhaust....as far as valve lash I have loosened up the rockers thinking they might be too snug and it still won't crank only backfiring and im lining up the opti's "double pin" to the Double slot on the cam gear and still only backfiring.....I have no clue I have torn this thing apart so much I could do it in my sleep now...some one please shed some light
the backfiring is trying to get unused compression out of the cylinders, def check to make sure your plug wires are in the correct order to the opti. and i know some cams have longer dowel pin lengths creating problems not letting the opti go on all the way, which can be fixed by shaving it down a little.