Help! Knock after opti install?
Help! Knock after opti install? Ok so i finished putting my opti in and it works fine. starts up and everything, but as soon as you touch the throttle it knocks. It sounds like its coming from the drivers side valve train (head). It only knocks when you hit the throttle. It revs up and everything. Doesn't backfire or anything. Im thinking i messed up a rocker or something when the opti **** on me on the highway. I was cruisin and it started to die and almost backfire and spuddered until it completely died. Im going to take the valve cover off after work and check it out and maybe adjust my valves/rockers. Does anybody have any insight on this? Any info would help.
Ok yesterday i took the valve cover off of the drivers side becuase thats where it sounded like it was coming from and saw nothing wrong. I even ran it with the cover off and everything looks good there. It only makes the knocking sound the second u hit the throttle. I took it for a ride around the neighborhood and it will just go with out hitting the gas. As soon as u touch it it makes that sound and wants to die and surges for a second. I dont want to make matters worse by driving it like this. It idles rough in gear. When its in park it idles alright but not normal after about 20-30 seconds it will die. Could i have messed up a valve???? Is there anyway to check with out pulling the head off? Someone please help. Thanks
On The Tree
Joined: Aug 2007
Posts: 148
Likes: 0
From: Warren, OH
I haven't tore my car down to get into re-setting my opti timing, but it sounds like it could be hellafied advanced, to the point where you are ignting much before TDC. This can cause the car to just be in a 'revved up' state going on its own, as the motor usually runs faster as you set the initial higher.
Any throttle input can cause a detonation/knocking noise if too advanced.
Any throttle input can cause a detonation/knocking noise if too advanced.
the opti only goes on one way and i am 100% sure i put it on right. I lined up the key way on the splines with the key way to the cam.
What do you mean by "re-setting the opti timing"?? This sounds like it could be possible but doesn't the computer control the timing? How would it be too advanced??
This is driving me crazy...
What do you mean by "re-setting the opti timing"?? This sounds like it could be possible but doesn't the computer control the timing? How would it be too advanced??
This is driving me crazy...
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ok heres another update, yesterday i started the car and it fired right up. i noticed the knocking sound got quieter but it still dies when u put it in gear and if u keep it going it just runs crappy. still makes the noise if u tap the throttle quickly. its not consistent it just does it as soon as u touch the throttle. Also when u put it in gear it wants to die. Could a valve be messed up?
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Launching!
Joined: Sep 2007
Posts: 245
Likes: 1
From: Clover, South Carolina
Remove all your plugs and inspect them cylinder by cylinder. Make sure all your wires are on tight and they have plenty of dielectric grease on them. If everything checks out there, I would pull all your rockers and pushrods. Check for marks on the rockers indicating incorrect metal to metal contact. Roll the pushrods on a flat surface to check for one being bent.
If all else checks ok, could very well be a valve. If so, you're looking at pulling one or both heads to find the culprit.
If all else checks ok, could very well be a valve. If so, you're looking at pulling one or both heads to find the culprit.
Remove all your plugs and inspect them cylinder by cylinder. Make sure all your wires are on tight and they have plenty of dielectric grease on them. If everything checks out there, I would pull all your rockers and pushrods. Check for marks on the rockers indicating incorrect metal to metal contact. Roll the pushrods on a flat surface to check for one being bent.
If all else checks ok, could very well be a valve. If so, you're looking at pulling one or both heads to find the culprit.
If all else checks ok, could very well be a valve. If so, you're looking at pulling one or both heads to find the culprit.
i changed the icm as well because i thought maybe that was it when i was diagnosing the no start but it wasnt so i returned it and put my stock one back on. I started the car before i put the water pump and pulley on to make sure it ran but didnt let it run long because i wasnt sure if it was good to not have the crank pulley on while running. So i never heard the knocking sound, i shut it off after i knew it started.
I know ive had messed up wire orders before and usually it will run really bad. this seems to idle fine and rev up fine. Actually it revs up but a lil slower then normal. Now that i think of it i remember looking at the #7 plug wire and it had a pretty bad kink in it as soon as it came off the plug. didnt think anything of it bc it ran fine before.
So they may be on right but that one could be causing this.
I will check the wires tomorrow and let u guys know. thanks for the help!!
I know ive had messed up wire orders before and usually it will run really bad. this seems to idle fine and rev up fine. Actually it revs up but a lil slower then normal. Now that i think of it i remember looking at the #7 plug wire and it had a pretty bad kink in it as soon as it came off the plug. didnt think anything of it bc it ran fine before.
So they may be on right but that one could be causing this.
I will check the wires tomorrow and let u guys know. thanks for the help!!
Ok still cant figure this out... The knock is predetonation i think. i think its an ignition problem.
My dad hooked up a SnapOn "Solus" scanner which gives live sensor data and everything. My car stays in open loop even after it gets warm. It was running for a while after it warms up. It had no codes stored at all. Nothing. The only thing he saw that was weird was an oil temp of -34 degrees?? does my car even have a oil temp sensor? theres none in the cluster. Other then the open loop and the oil temp there seems to be nothing wrong. Why would it be stuck in open loop?
Any input??
My dad hooked up a SnapOn "Solus" scanner which gives live sensor data and everything. My car stays in open loop even after it gets warm. It was running for a while after it warms up. It had no codes stored at all. Nothing. The only thing he saw that was weird was an oil temp of -34 degrees?? does my car even have a oil temp sensor? theres none in the cluster. Other then the open loop and the oil temp there seems to be nothing wrong. Why would it be stuck in open loop?
Any input??
i had the same problem. i put my opti in and they told me the sline type pin that goes from the opti into your motor would only go one way but it can be easily pushed in the wrong way but it took me forever to figure out! Does it crank ok?? Or does it crank different then before like the batteries low??
thats what im thinking, i payed very close attention when i put it on and i was sure it was on right but maybe i did mess it up. Just dont want to tear it down again to find out it was right.
As far as how it turns over, why do u ask?? I had a problem with the starter before hand i think my solenoid is going. Its been sitting alot so i thought maybe the battery was dieng anyway. It grinds sometimes too. But it does start up fine. It idles but not consistently. It like starts to stumble and then catches its self. Idles a little high.
I think i may have it off a spline!
As far as how it turns over, why do u ask?? I had a problem with the starter before hand i think my solenoid is going. Its been sitting alot so i thought maybe the battery was dieng anyway. It grinds sometimes too. But it does start up fine. It idles but not consistently. It like starts to stumble and then catches its self. Idles a little high.
I think i may have it off a spline!
i would just tear it back down i know it sux but an opti going bad wouldnt knock your valve train out of whack it sounds like ignition if its detonating or a timing knock which would be like i had and the reoson i asked how it cranked is because mine would like drag or crank weird like fast then slow and idle high just back-track what you done to eliminate that 1st and make sure your pin on your opti slides in easy and all your plug wires are in the right order and good luck.The inconsistant idleing and knockin definetly sounds exactly like the problem i had with my opti.
Last edited by snk-huntr; Dec 27, 2007 at 01:15 AM.
pin in wrong! I want everyone to know that it is possible to get it on and sit flush with out forcing it. That thing was really a bad design. So some advice for people in the future... BE VERY CAREFUL & PAY CLOSE ATTENTION. :-)