werid tach wobble

Post by **Structure240sx** » Thu Dec 25, 2003 7:32 am

since i started beating on my car since i put in the new engine and did the 5spd swap im having a lil problem. in 4th gear at 5k+rpms and 5th gear 4k+rpms my tach needle will sort of wobble back and forth a couple hundred rpms while it climbs up. the only thing i can think of thats happening is the computer is retarding timing a whole lot which would mean im getting knock right? but i dont hear knock detonation backfiring nothin. plus before on my stock engine beign auto i was overboosting 10-11psi and didnt have this problem. im using the same type of spark plugs same distributor

one difference i can think of is i had to switch ove my knock sensor cuz hte previous owner of the engine was using an SDS. of course i forgot to put the knock sensor on while i had the intake mani off. buti got it on and tightened it down. but the side where the wire comes out of it points down instead of toward the front of the engine. this prolly doesnt matter but jsut what im thinkin of maybe i dont have the knock sensor in right or tighented enough? thanks anyone who can help

Post by **j-z** » Thu Dec 25, 2003 7:32 am

maybe you possibly messed something up while doing the transmission swap.

Post by **Structure240sx** » Thu Dec 25, 2003 7:32 am

the cltuch used to slip often but not too much now. is it possible that it would slip slightly then grab under laod like that? maybe jsut a bad transmission? i have a new disc im waitin to put in for when i pick up a newer transmission. im not tryin to push 15psi on a 130,000mi transmission. my jwt ecu nismo injectors and z32 maf will be goin in next week along with a bung or the wideband o2 sensor my uncles shop uses so that should take care of timing and i can see if its the engine. im thinkin more of a transmission problem tho now. who knows

Post by **j-z** » Thu Dec 25, 2003 7:32 am

yeah i dont think your ignition timing would have anything to do with your tach fluctuating like that. i think its something transmission related.

Post by **klattr1** » Thu Dec 25, 2003 7:32 am

yeah its gotta be it slippin.Make sure your disc is not put in backwards and also that you dont have the clutch adjustment rod twisted too far also. Do u have a new throwout bearing in your transmission also and if so did u properly grease it so that it doesnt get stuck on shaft at all?

Post by **C-Kwik** » Thu Dec 25, 2003 7:32 am

If the engine was jumping around like that over a few hundred RPM's, you would feel it. If you don't feel it, it's likely an issue with the tach, engine speed sensor or something in between.

Post by **MikeMurphy** » Thu Dec 25, 2003 7:32 am

isnt that speed-governor territory?

good luck.

Post by **95_240sx** » Thu Dec 25, 2003 7:32 am

5th gear at 5250 rpm = 119mph on stock tires/wheels. Thats why with a 5spd you can put it in 5th with the clutch in and it will bouce at 5250. Youd notice it up that high jumping around a couple hundred rpms.

Rick

Post by **Structure240sx** » Thu Dec 25, 2003 7:32 am

i did put in a new throw out bearing and greased it but possibly not enough. the fsm said grease it but not too much so i just kinda guessed. im pretty sure i put the clutch int he right way would it even work if i didnt?i dont have a speed governor on my caronce i get get a newer transmission ill put in my new clutch and another through out bearing, greas them up a lil better and see what happens. should only be a ouple weeks. i just wanted tom ake sure its not my timing jumping around and im about to blow my motor

thanks fellas

Post by **klattr1** » Thu Dec 25, 2003 7:32 am

i had some clutch problems on my car for a while. The problem i had was that the throwout bearing was getting caught up on the shaft as i would push in the clutch. When i pulled the transmission and i would push the clutch in, I could see the the clutch fork moving but the throwout bearing would not move out all the way. So i just bought a new throwout bearing and greased it better and everything was fixed. I was getting harsh engagements and alot of slipping but now its perfect!

Post by **Structure240sx** » Thu Dec 25, 2003 7:32 am

hmm ur making me feel alot better now. i really dont thinki greased it that good

Post by **Structure240sx** » Thu Dec 25, 2003 7:32 am

yea cuz my engagemetn is pretty harsh i thought it might have been cuz i bypassed the clutch damper system but i usually cant get it to shift smooth unless im drive hard

Post by **klattr1** » Thu Dec 25, 2003 7:32 am

make sure that you dont just grease the same throwout bearing that you got in there now. Make sure and get a new one and grease it up good.

Post by **Structure240sx** » Thu Dec 25, 2003 7:32 am

yea i will they're like $45. and the clutch seems good. i was driving hard tonight. raced a gsx 3 times. beat him once and dead even with him once. hes got quite a luanch advantage. he said hes runnign 12psi anyone know how much boost they run stock? or is it 12, he claims no boost controller

Post by **littlemilla3** » Thu Dec 25, 2003 7:32 am

Structure240sx wrote:yea i will they're like $45. and the clutch seems good. i was driving hard tonight. raced a gsx 3 times. beat him once and dead even with him once. hes got quite a luanch advantage. he said hes runnign 12psi anyone know how much boost they run stock? or is it 12, he claims no boost controller

They run 10 psi stock. He was probably running more because exhaust and other bolt ons increase the boost a few psi.

Post by **Structure240sx** » Thu Dec 25, 2003 7:32 am

i guess since he has apexi gt spec exhuast exhuast i think and a turbo xs rfl but why would hte wastegate open later? not really important

werid tach wobble

werid tach wobble

hey

hey

hey

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