missed shift - broken what? *** update
missed shift - broken what? *** update Heading down to the track tonight missed a shift for the first time ever like this, and I guess it all caught up to me. Was in third about 5000 rpms and went to shift to fourth, nope...hit second.
Ok, so I'm pissed. SES light on immediatly (never went off on the 20 mile drive home), rough rough low (500) idle for a while, rough in every gear below 1500 rpm. I let it sit for a while, cleared up the low idle speed, but it's still rough everywhere. Noise is quite distinct outside of the car. Almost like a tapping, brushing like noise. Kinda sounds like its fluttering too. I'm pretty sure it's a valve. Had a few buddies listen, most were clueless, one said a valve spring, I thought just a bent pushrod at first (actually I was really hoping for just that), but I think it's a valve.
Any other ideas? And what's it cost to get a valve replaced or something in the similar area?
<small>[ February 06, 2003, 07:06 PM: Message edited by: jd13 ]</small>
Ok, so I'm pissed. SES light on immediatly (never went off on the 20 mile drive home), rough rough low (500) idle for a while, rough in every gear below 1500 rpm. I let it sit for a while, cleared up the low idle speed, but it's still rough everywhere. Noise is quite distinct outside of the car. Almost like a tapping, brushing like noise. Kinda sounds like its fluttering too. I'm pretty sure it's a valve. Had a few buddies listen, most were clueless, one said a valve spring, I thought just a bent pushrod at first (actually I was really hoping for just that), but I think it's a valve.
Any other ideas? And what's it cost to get a valve replaced or something in the similar area?
<small>[ February 06, 2003, 07:06 PM: Message edited by: jd13 ]</small>
TECH Senior Member
Joined: Nov 2001
Posts: 11,603
Likes: 0
From: Chi-Town, IL
Re: missed shift - broken what? *** update yea, you probably floated the valves pretty good, could be a few bent ones in there, maybe a valvespring too.... <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
Re: missed shift - broken what? *** update The more I read about valve springs etc, the more I'm thinking it is just a valve spring. I really don't think I've dropped the valve yet. *Hopefully*
Money is tight, and so is time. I'm taking it to a dealership tomorrow for an estimate. I don't have the tools currently, nor the time for nearly 2 weeks to do anything half way inept in the car. <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
Money is tight, and so is time. I'm taking it to a dealership tomorrow for an estimate. I don't have the tools currently, nor the time for nearly 2 weeks to do anything half way inept in the car. <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
On The Tree
Joined: Jun 2002
Posts: 123
Likes: 0
From: San Diego
Re: missed shift - broken what? *** update If you smacked the valve into the piston, i believe you'll have to have the valve seat machined as well as a new valve.
Could be the pushrods, could be the springs, could be valves. You can't know until heads are off. I'd think pushrods and maybe valves, if a spring broke and you have single springs i'd think you woulda dropped a valve by now.
Could be the pushrods, could be the springs, could be valves. You can't know until heads are off. I'd think pushrods and maybe valves, if a spring broke and you have single springs i'd think you woulda dropped a valve by now.
TECH Addict
Joined: Dec 2001
Posts: 2,298
Likes: 2
From: new england
Re: missed shift - broken what? *** update Do your self a favor and install 918 springs while heads are off. Even without cam these springs would save you from this kind of problem in future. I backshifted twice and i have shaved heads and cam installed, never any damage. Stock springs cant handle very much.You prolly only hit like 6200 rpm backshifting from 3rd to 2nd at 5000 rpm, i was alot higher than that still no damage.
<small>[ February 06, 2003, 05:37 AM: Message edited by: LS1derfull ]</small>
<small>[ February 06, 2003, 05:37 AM: Message edited by: LS1derfull ]</small>
Teching In
Joined: Dec 2002
Posts: 24
Likes: 0
From: Overlandpark, KS 66213
Re: missed shift - broken what? *** update <img border="0" title="" alt="[Mad]" src="gr_images/icons/mad.gif" /> same thing happened to me on a miss shift and bent a valve. M6 is great but the old M4 days you had the outside rail for speed shifting...elbows out.
<small>[ February 06, 2003, 08:50 AM: Message edited by: rh2772 ]</small>
<small>[ February 06, 2003, 08:50 AM: Message edited by: rh2772 ]</small>
Trending Topics
Re: missed shift - broken what? *** update Got the car in to be looked at today. Wasn't burning oil so that was an initial good sign. Compression check, perfect. Although...
Somehow I blew out the coil packs and plug wires on 5 and 6.
The guy who was checking out my car left for the day so he's gonna continue tomorrow morning. This is a lot better news than I thought, no internal damage so far.
Somehow I blew out the coil packs and plug wires on 5 and 6.
The guy who was checking out my car left for the day so he's gonna continue tomorrow morning. This is a lot better news than I thought, no internal damage so far.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Re: missed shift - broken what? *** update Yeah that doesn't even sound right. I did the same thing and bent 3 pushrods and 3 intake valves along with all my pistons having valve marks in them now. Gave me a good reason to build a big motor though.
Re: missed shift - broken what? *** update I've seen mostly bent pushrods.
One buddy a few years ago did a horrendous powershift and bent ALL of his intake valves.
Go and install some LS6 valvesprings if you can.
One buddy a few years ago did a horrendous powershift and bent ALL of his intake valves.
Go and install some LS6 valvesprings if you can.
Re: missed shift - broken what? *** update If the car has a rough idle, and an SES lite, maybe also a slight ticking/clacking noise, then you might have a bent pushrod or two.
If you have a flickering SES lite, and the car has a very very rough idle, you might have some bent valves.
If you have a flickering SES lite, and the car has a very very rough idle, you might have some bent valves.
TECH Fanatic
Joined: Nov 2001
Posts: 1,695
Likes: 9
From: Raleigh, NC
Re: missed shift - broken what? *** update </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Silver Lining:
<strong> Would it hurt anything if you missed a gear goin from 2nd to 3rd (but didnt go in third, just hit the gate) and reved really high?
Thanks,
Greg </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Shouldn't. The rev-limiter should be sufficient to protect the engine. The case above is a manual over-rev (forcing the engine to rev past the rev limiter by shifting to the wrong gear at the wrong time. The dreaded 3-2 is pretty common with these trannys, the shift gate is a lil strange.
For those reading it is a good idea to cup your hand around the left side of the shifter when shifting from 3-4. I actually rotate my hand 90 degrees (thumb down) with the palm of my hand facing the passenger side of the vehicle in-between me and the shifter. I have never missed a 3-4 since I started doing this <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> .
<strong> Would it hurt anything if you missed a gear goin from 2nd to 3rd (but didnt go in third, just hit the gate) and reved really high?
Thanks,
Greg </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Shouldn't. The rev-limiter should be sufficient to protect the engine. The case above is a manual over-rev (forcing the engine to rev past the rev limiter by shifting to the wrong gear at the wrong time. The dreaded 3-2 is pretty common with these trannys, the shift gate is a lil strange.
For those reading it is a good idea to cup your hand around the left side of the shifter when shifting from 3-4. I actually rotate my hand 90 degrees (thumb down) with the palm of my hand facing the passenger side of the vehicle in-between me and the shifter. I have never missed a 3-4 since I started doing this <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> .
Re: missed shift - broken what? *** update </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">For those reading it is a good idea to cup your hand around the left side of the shifter when shifting from 3-4. I actually rotate my hand 90 degrees (thumb down) with the palm of my hand facing the passenger side of the vehicle in-between me and the shifter. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I usually do this actually, this time I didn't and I paid. <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Would it hurt anything if you missed a gear goin from 2nd to 3rd (but didnt go in third, just hit the gate) and reved really high? </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Depends on how high you revved. I've done this before actually, revved to about 6500 or so and everything was fine. I hear about people doing this all the time, 90% of the time everything is fine.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Did you blow out header gasket and damage wires and coil pack from heat? Otherwise that doesnt make sense. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Compression test showed up good. I'm pretty sure the gasket isn't blown. I don't understand this at all either. But two blown coil packs definatly sounds better than some messed up valves to me.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Would it hurt anything if you missed a gear goin from 2nd to 3rd (but didnt go in third, just hit the gate) and reved really high? </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Depends on how high you revved. I've done this before actually, revved to about 6500 or so and everything was fine. I hear about people doing this all the time, 90% of the time everything is fine.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Did you blow out header gasket and damage wires and coil pack from heat? Otherwise that doesnt make sense. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Compression test showed up good. I'm pretty sure the gasket isn't blown. I don't understand this at all either. But two blown coil packs definatly sounds better than some messed up valves to me.
Re: missed shift - broken what? *** update man, I consider myself really lucky...I've done the 3-2 shift THREE times and not 1 bent pushrod or valve. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> That was with the stock non-hurst shifter tho, I have a Ripper now and never miss ANY shifts <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
