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Mis-shifted 3rd to 2nd, engine underpowered now?

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Old 07-26-2008, 12:08 AM
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Default Mis-shifted 3rd to 2nd, engine underpowered now?

I miss shifted 3rd to 2nd, I was at about 4.5-5k and i hit 2nd, I immedately hit the clutch and let it out, but it make this horrible GUNK type noise. Now the engine sounds funny, almost as if once cylinder isnt firing or firing very well. It idles fine but seems to has a little hesistation starting up. When i get on it, the car feels like it is under powered. Background info on the car is a bolton LS1 00 z28, i/h/e ls6 manifold. Im thinking maybe i bent a pushrod or bent a valve. What do you guys think could be wrong with my engine? Please help, any input is greatly appreciated.
Old 07-26-2008, 05:14 AM
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DO NOT DRIVE IT AGAIN. REPEAT. DO NOT DRIVE IT AGAIN.

first of all, i dont know why you would be flogging it like that after missing a shift and noticing something wrong.

pull the valve covers and check for bent pushrods, and any other problem.............naw. forget that, go ahead and pull the intake, accessories and heads. cause your gonna need some work.

one more thing.......learn to drive.
Old 07-26-2008, 06:58 AM
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I had a issue like that with my Corvette. Mine had a bent valve, but sometimes you get lucky and only tweak a pushrod. Do a compression test.
Old 07-26-2008, 07:45 AM
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i hit the rev limiter in mine and it started making this horrible tapping noise. everybody and 2 different shops told me it was just an exhaust leak so i drove on it longer before checking it. i found out that i bent a pushrod, which messed up my head and lifter tray. it wont take long to take your coil packs, valve cover, and rocker arms. hopefully its nothing to bad. let us know what you find.
Old 07-26-2008, 09:22 AM
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You either bent a push rod or a valve or both..as was posted above do not drive the car do not start the engine...get a piece of glass and remove push rods and roll them on the glass to check for straightness...if they are all straight you probably have a bent valve or valves...run a leak down test on all cylinders and you will find the leaking cylinders with the bent valves ...

Part 2 Pull head or heads and do a valve job and replace the bent valves...or better yet replace heads with some better heads

Part 3 Driver's ed.

Last edited by slt200mph; 07-26-2008 at 10:11 AM.
Old 07-26-2008, 09:31 AM
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so you were shifting from 3rd-4th and you went into 2nd by accident?? If so im suprised it didnt just blow the clutch
Old 07-26-2008, 10:21 AM
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3-2 is a common mistake for newer drivers, given how much the engine torques itself side to side and a stock transmission mount coupled with a shitty low feedback feel shifter with long throws...

seriously... don't drive, pull covers and inspect the pushrods. Odds are some are bent, if not worse a bent valve...
Old 07-26-2008, 10:45 AM
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I have a b&m shifter and it gives me hell, its not a pro 5.0. The clutch is a ram hd. If the vales are bent what a batter time for h/c?
Old 07-26-2008, 02:31 PM
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i did the same thing a couple days ago, my hurst handle was loose, so i had it turned upside down and a 91 383cid camaro tried racing me and i went from 3rd-2nd on accident at about 70mph with 4.10's. Made a nice band and when i glanced at the tack as i pressed in the clutch the rpm's were between 6900-7100. Runs like new still!
Old 07-26-2008, 02:33 PM
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Originally Posted by scottHMT
I miss shifted 3rd to 2nd, I was at about 4.5-5k and i hit 2nd, I immedately hit the clutch and let it out, but it make this horrible GUNK type noise. Now the engine sounds funny, almost as if once cylinder isnt firing or firing very well. It idles fine but seems to has a little hesistation starting up. When i get on it, the car feels like it is under powered. Background info on the car is a bolton LS1 00 z28, i/h/e ls6 manifold. Im thinking maybe i bent a pushrod or bent a valve. What do you guys think could be wrong with my engine? Please help, any input is greatly appreciated.
If you have the stock "weak" pushrods, i'm sure you bent one or more of them, either pulls the covers and all, or do a compression check, and go from there.
Old 07-26-2008, 02:40 PM
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What really sucks is that my garage is getting remodeled, and my driveway is full of **** on the plus side I have began looking at H/C swaps, becasue if i have a bent valve I might aswell upgrade. From what i've read Im htinking its a bent valve. Sitting at idle and giving it a quick rev to about 2-2.5k you can hear an obvious misfire. under more throttle it seems to go away. I'll tow the car home and deal with it in a few weeks. Thanks everyone.
Old 07-26-2008, 02:47 PM
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that sucks man, but with all those factors, it definitely got something thrown out of wack. i got lucky when it happened to me, no funny noises afterwards, and (after putting in a short stick, lol) took it to the track and it most certainly wasn't down on power
Old 07-26-2008, 04:04 PM
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Before you do all that work, check your plugs - may have had some detonation and blown off the ground strap. Will still fire under light load, but blow out under anything else....

Always check the simple stuff first.

Bird
Old 07-26-2008, 04:18 PM
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Originally Posted by back in black
DO NOT DRIVE IT AGAIN. REPEAT. DO NOT DRIVE IT AGAIN.

first of all, i dont know why you would be flogging it like that after missing a shift and noticing something wrong.

pull the valve covers and check for bent pushrods, and any other problem.............naw. forget that, go ahead and pull the intake, accessories and heads. cause your gonna need some work.

one more thing.......learn to drive.
Your an idiot. He doesnt have to get into pullin the heads yet..jesus christ. He probably just needs to pull the valve covers. Its most likely a bent pushrod. I did the same thing but went from the top of 2nd back into 1st. I still drove mine after which helped me diagnose the problem. **** happens...if you've never missed a gear then your shiftin like a *****.
Old 07-26-2008, 04:40 PM
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Originally Posted by tenacious z
Your an idiot. He doesnt have to get into pullin the heads yet..jesus christ. He probably just needs to pull the valve covers. Its most likely a bent pushrod. I did the same thing but went from the top of 2nd back into 1st. I still drove mine after which helped me diagnose the problem. **** happens...if you've never missed a gear then your shiftin like a *****.
^ I don't know who this guy is but he makes more sense than most people in here. I especially love that last sentence! If you're shifting like a *****, you're not going fast enough!
Old 07-26-2008, 04:41 PM
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Originally Posted by tenacious z
Your an idiot. He doesnt have to get into pullin the heads yet..jesus christ. He probably just needs to pull the valve covers. Its most likely a bent pushrod. I did the same thing but went from the top of 2nd back into 1st. I still drove mine after which helped me diagnose the problem. **** happens...if you've never missed a gear then your shiftin like a *****.
I agree. Pull the valve covers off, pull the rockers out, and take the pushrods out. Most likey it is just a bent pushrod if they are still the factory ones.
Old 07-26-2008, 05:36 PM
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um, missing a gear and shifting from 3rd to 2nd is two different things. only time i ever "missed" a gear was AFTER my syncro's in third started to go from SPEED SHIFTING.

some people can shift better then others. some cant. my 6 speed sounds like a 4l60 with shift kit. my foot never comes off the carpet......
Old 07-26-2008, 06:37 PM
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Originally Posted by back in black
um, missing a gear and shifting from 3rd to 2nd is two different things. only time i ever "missed" a gear was AFTER my syncro's in third started to go from SPEED SHIFTING.

some people can shift better then others. some cant. my 6 speed sounds like a 4l60 with shift kit. my foot never comes off the carpet......
Yea, maybe your a great shifter but it is not uncommon for newbs to shift into a lower gear and mechanically overrev. And pulling heads is unnecessary to change the pushrods (which is the most likely culprit).

The reason people got on your *** is because your post gave us the impression that
1) You are a ******** that is jumping down a newbs throat w/o being provoked
2) You don't really know what you are talking about

Unfortunately both characteristics are things that this site trys to avoid. Being a ******** and flamming newbs for making common mistakes is bad because it discourages them from asking questions (which is sorta the point of this site). Also, making suggestions that are based on an inadequate knowledge base lowers the aggregate quality of the feedback people recieve on this site. Please don't be offended by this, but keep it in mind in future posts.
Old 07-26-2008, 07:01 PM
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I had a simelar problem.... i hit the red rev i was on 2 gear then the ticking sound came. shops told me that it was headers gaskit on the passenger side. i replace it and still the sound didn`t go not even dicreased. i removed the valve cover i found a bent pushrod.
Old 07-26-2008, 09:03 PM
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it wasnt based on inexperience.

i have rebuilt all sorts of motors before from this same sort of problem.

somehow a piston smacks a valve and bends a pushrod. the person does a compression and leakdown test and it seems fine, then they take everyone elses (while your workin on it) advice and upgrades the springs and cam and pushrods. or sometimes just the pushrods or pushrods and springs depending of cam. then shortly there after they have a blown engine because of the valve stem breaking off the valve.

i just like to do it right, better to spend a lil more now then alot later... my $.02


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