RPM up and down ?
Thread Starter
Supreme Member
Joined: Jul 2001
Posts: 2,398
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From: Baton Rouge ,Louisiana ,USA
RPM up and down ?
In addition to the shaking problem I am having , at the same time my rpm at about 2000 goes up to 24 then down to 2000 then up again to 24 like its missing you know . thanx guys , Wayne 
Shaking Problem
Towards the end of acceleration when my car is about to downshift , it starts to shake terribly .Sometimes does not stop until I take my foot off the gas and start to slow down 1 mph or so .It seems like it starts shaking from the back then works its way to the front fast .It first started doing this about 8 months ago , it has been checked by a mechanic several times , but they can't find anything .But now its gotten to the point where its so bad that it does it every time I accelerate and it does it for longer periods of times .And more often I have to take my foot of the gas and slow down a tad bit to get it to stop .Anyone have a clue to what it is ? lol Thanx in advance , Wayne
Shaking Problem
Towards the end of acceleration when my car is about to downshift , it starts to shake terribly .Sometimes does not stop until I take my foot off the gas and start to slow down 1 mph or so .It seems like it starts shaking from the back then works its way to the front fast .It first started doing this about 8 months ago , it has been checked by a mechanic several times , but they can't find anything .But now its gotten to the point where its so bad that it does it every time I accelerate and it does it for longer periods of times .And more often I have to take my foot of the gas and slow down a tad bit to get it to stop .Anyone have a clue to what it is ? lol Thanx in advance , Wayne
Supreme Member
Joined: Jan 2001
Posts: 7,604
Likes: 1
From: ****SoCal, USA****
Have your tranny checked.
Try this.
Try to duplicate the RPM occurance in
holding 2nd gear
holding 3rd gear.
Could be the TC lock/unlock.
What speed?
------------------
Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA
Try this.
Try to duplicate the RPM occurance in
holding 2nd gear
holding 3rd gear.
Could be the TC lock/unlock.
What speed?
------------------
Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA
Supreme Member
Joined: Jan 2001
Posts: 7,604
Likes: 1
From: ****SoCal, USA****
MAYBE, but doubt it.
I would really try this.
When ya next feel it occur, lighten up on the gas pedal. See what happens.
IT COULD BE THE TC locking/unlocking.
That's why I suggested trying different engine speeds/RPM, duplicating any instance you can to keep observing what's happening.
It could be affected by cruising speeds in your area and the hills, wanting to impress people with engine noise, etc. all can contirbute. Keep making it happen keep observing, tho.
You may find the answer soon!
IF REALLY IN DOUBT, find a good tranny shop, take the guy for ride, duplicate the problem for him & he may know better. Seek higher knowledge.
Bummer, we can't go for rides to hear the problems. Maybe this ears Computers for Christmas may have that option (Ride Along Camera like in race cars!!!!).
It would be really cool.
Imagine us try to impress everyone with their latest rides. Can you hear Tom's Girlfriend screaming as Tom shows her how the new sway bars works!!
------------------
Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA
[This message has been edited by KED85 (edited August 26, 2001).]
[This message has been edited by KED85 (edited August 26, 2001).]
I would really try this.
When ya next feel it occur, lighten up on the gas pedal. See what happens.
IT COULD BE THE TC locking/unlocking.
That's why I suggested trying different engine speeds/RPM, duplicating any instance you can to keep observing what's happening.
It could be affected by cruising speeds in your area and the hills, wanting to impress people with engine noise, etc. all can contirbute. Keep making it happen keep observing, tho.
You may find the answer soon!
IF REALLY IN DOUBT, find a good tranny shop, take the guy for ride, duplicate the problem for him & he may know better. Seek higher knowledge.
Bummer, we can't go for rides to hear the problems. Maybe this ears Computers for Christmas may have that option (Ride Along Camera like in race cars!!!!).
It would be really cool.
Imagine us try to impress everyone with their latest rides. Can you hear Tom's Girlfriend screaming as Tom shows her how the new sway bars works!!
------------------
Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA
[This message has been edited by KED85 (edited August 26, 2001).]
[This message has been edited by KED85 (edited August 26, 2001).]
Thread Starter
Supreme Member
Joined: Jul 2001
Posts: 2,398
Likes: 1
From: Baton Rouge ,Louisiana ,USA
Yeah , I should have mentioned that , when I do let off the gas , even if I let off a slight bit , it stops shaking immediately .Have not watched the rpm's yet to see what that does . but the rpm just started jumping like that recently .Yeah the cam would be cool hehe ,you could hear what a dynamax super turbo sounds like with a gutted cat 
..Thanx buddy , Wayne
..Thanx buddy , Wayne 
Supreme Member
Joined: Jan 2001
Posts: 1,221
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From: Halifax, NS,Canada
Car: 1995 Z28
Engine: LT1
Transmission: Built 4L60E
Axle/Gears: 3.23's - Limited Slip
Wayne,
I was having this 2000-2400 jump problem for a while, and it turned out the wire to the tach had broken off inside and was making a poor contact, so I replaced that section of wire and it is working fine now...
I was having this 2000-2400 jump problem for a while, and it turned out the wire to the tach had broken off inside and was making a poor contact, so I replaced that section of wire and it is working fine now...
Supreme Member
Joined: Jan 2001
Posts: 7,604
Likes: 1
From: ****SoCal, USA****
I'd rather see all these "cute" girlfriends (nod-nod, wink-wink)!!!
Sounds like I gave ya clues, COOL!
It shakes/shudders, right?
You could just need a tune up, also.
Why?
At the low RPMS (cruising), the engine is not "torque" happy (not making enough power).
Giving a tune up will return some low end spunk.
DO ya keep it in third under a steady 50 MPH in town areas?
That helps.
Have ya changed tranny fluid lately?
IF really suspicious (of tranny), go to a good tranny shop, take a guy for a test ride
Ya feel it in the seat of your pants, also?
------------------
Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA
Sounds like I gave ya clues, COOL!
It shakes/shudders, right?
You could just need a tune up, also.
Why?
At the low RPMS (cruising), the engine is not "torque" happy (not making enough power).
Giving a tune up will return some low end spunk.
DO ya keep it in third under a steady 50 MPH in town areas?
That helps.
Have ya changed tranny fluid lately?
IF really suspicious (of tranny), go to a good tranny shop, take a guy for a test ride
Ya feel it in the seat of your pants, also?
------------------
Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA
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Thread Starter
Supreme Member
Joined: Jul 2001
Posts: 2,398
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From: Baton Rouge ,Louisiana ,USA
Karl , hey man !
I have new plugwires , sparkplugs , but have not changed the cap and rotar in awhile.I think the rpm going up and down maybe just coweincedence with the shaking .Its been gosh , prabably 30 or 40 thousand miles ago sence I got a new cap and rotar , So I know I prabably need one anyway .As for as the shaking that only happens on fri and sat nights , I figured out what that was hehe j/k ..Im just ganna have to bring it to the shop .I was wondering if it could even be my u-joints.....If its not any of these then i will check my rpm cable .Thanx Karl and Joe for your help , Wayne
I have new plugwires , sparkplugs , but have not changed the cap and rotar in awhile.I think the rpm going up and down maybe just coweincedence with the shaking .Its been gosh , prabably 30 or 40 thousand miles ago sence I got a new cap and rotar , So I know I prabably need one anyway .As for as the shaking that only happens on fri and sat nights , I figured out what that was hehe
j/k ..Im just ganna have to bring it to the shop .I was wondering if it could even be my u-joints.....If its not any of these then i will check my rpm cable .Thanx Karl and Joe for your help , Wayne Supreme Member
Joined: Jan 2001
Posts: 7,604
Likes: 1
From: ****SoCal, USA****
You have electonics feeding the RPM to the tach. Check the wires for good connections. A tune up never hurts.
Watch all the places ya put you rhands so you can figure out if ya need to fix anything.
ALSO, cap, put it besides the current one. Make sure they are in identical positioning! MAKE ßRE.
SWAP One wire at a time!
Helps make this fool proof! Then make sure those wires need not come off.
You'll need a short philips for those cap screws.
------------------
Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA
Watch all the places ya put you rhands so you can figure out if ya need to fix anything.
ALSO, cap, put it besides the current one. Make sure they are in identical positioning! MAKE ßRE.
SWAP One wire at a time!
Helps make this fool proof! Then make sure those wires need not come off.
You'll need a short philips for those cap screws.
------------------
Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA
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