LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Transmission / Speedometer Problems

Thread Tools
 
Search this Thread
 
Old 04-29-2012, 09:55 AM
  #1  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
jasonz28camaro's Avatar
 
Join Date: Sep 2006
Location: Houston
Posts: 593
Received 7 Likes on 7 Posts

Default Transmission / Speedometer Problems

When I'm driving on the highway in 4th gear the speedometer jumps around like crazy reading anywhere from 30-50mph and the trans will down shift back and forth from 3rd to 4th.

The trans is a 4L60e that has no known problems. I did a search and could not find anything like this, hope you guys have some answers.

Also, could this be causing a misfire if I was driving it hard in the lower gears. The reason i ask is because i was getting it dyno tuned and the tuner was complaining about the speedo moving around and there was also a bad misfire after 4K.

Thanks!
Old 04-29-2012, 01:14 PM
  #2  
TECH Regular
 
bizerk1's Avatar
 
Join Date: Jan 2011
Location: Nw suburbs chicago
Posts: 468
Likes: 0
Received 0 Likes on 0 Posts
Default

Transmission shift solenoid??
Old 04-29-2012, 09:25 PM
  #3  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
jasonz28camaro's Avatar
 
Join Date: Sep 2006
Location: Houston
Posts: 593
Received 7 Likes on 7 Posts

Default

Now the car won't shift out of 1st. Any thoughts?
Old 04-30-2012, 08:27 AM
  #4  
TECH Fanatic
iTrader: (8)
 
96TransAmboosted's Avatar
 
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes on 0 Posts
Default

Whats the flyid look like?
Miles on tranny?
Could be a dirty valve body or a solinoid malfunction. Need to do some test on it.
Old 04-30-2012, 08:49 AM
  #5  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
jasonz28camaro's Avatar
 
Join Date: Sep 2006
Location: Houston
Posts: 593
Received 7 Likes on 7 Posts

Default

The trams has about 5k miles on it.
Fluid is fine, not sure of the valve body?

I spoke to a mechanic last night and he told me that the VSS (speed sensor on the tail shaft could be damaged and leaking trans fluid inside the plug causing it to short. I unplugged it last night and there was some fluid inside the female section of the plug, not sure what it wast, too little and too dirty. On the pigtail there was oil on all the wires, both ends of the rubber wire seals and also inside in-between the rubber seals. I cleaned all this real good and I'll see how it drives this morning.

All this fluid could deffinently cause a short. I'll check the female section of the sensor after I drive it and see if it is leaking.
Old 04-30-2012, 09:46 AM
  #6  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
jasonz28camaro's Avatar
 
Join Date: Sep 2006
Location: Houston
Posts: 593
Received 7 Likes on 7 Posts

Default

so cleaning the plug did nothing, still is stuck in 1st or maybe another gear. all i know is that it is not changing gears.

Im going to try to replace the VSS and see if that can fix the problem. Could this even be my problem now or could i have burnt up some clutches when the car was shifting from 4th to 3rd and not it wont shift because the clutches are bad???
Old 04-30-2012, 10:27 AM
  #7  
TECH Addict
iTrader: (1)
 
jaycenk's Avatar
 
Join Date: Jun 2009
Location: Holiday, FL
Posts: 2,210
Received 1 Like on 1 Post

Default

Try replacing the VSS. If the speedo was jumping around like crazy just before you had the problem with it not shifting out of first there is a good possibility either the VSS is bad or the wires that go to the VSS are damaged. PCM uses the VSS with other sensors to choose shift points at different throttle positions / Load and speeds.
Old 04-30-2012, 08:57 PM
  #8  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
jasonz28camaro's Avatar
 
Join Date: Sep 2006
Location: Houston
Posts: 593
Received 7 Likes on 7 Posts

Default

Originally Posted by jaycenk
Try replacing the VSS. If the speedo was jumping around like crazy just before you had the problem with it not shifting out of first there is a good possibility either the VSS is bad or the wires that go to the VSS are damaged. PCM uses the VSS with other sensors to choose shift points at different throttle positions / Load and speeds.
I did that earlier today and it might solve the problem with the speedo but it wont shift out of 1st still.

So one problem might be solved but i gained a new one lol.

I'm having my soon father inlaw come by tomorrow with a tech II and he is going to check for a few things to try to narrow the problem down. He named a bunch of things he could look at and test but if anyone has any suggestions let me know.
Old 04-30-2012, 09:08 PM
  #9  
TECH Senior Member
iTrader: (2)
 
RamAir95TA's Avatar
 
Join Date: May 2005
Location: South Jersey
Posts: 9,467
Likes: 0
Received 6 Likes on 6 Posts

Default

I would immediately suspect the VSS before anything else. If the PCM doesn't see a consistent pulse from the VSS it can do all sorts of weird things, including not shifting out of first. The VSS wiring is pretty lengthy and can easily become pinched because of how it's routed. The fact that it's covered in split-loom tubing doesn't help much either.

If you're handy with a multimeter you can check the wiring for continuity.
Old 04-30-2012, 09:56 PM
  #10  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
jasonz28camaro's Avatar
 
Join Date: Sep 2006
Location: Houston
Posts: 593
Received 7 Likes on 7 Posts

Default

I'll try that out tomorrow evening. If it's not the sensor then there is a good chance it could be the wires. We are going to check the VSS on the scanner tomorrow to see how it's acting, if it's crazy that will make it point to the wires.
Old 05-02-2012, 03:47 PM
  #11  
TECH Resident
iTrader: (1)
 
tricked94camaro's Avatar
 
Join Date: May 2010
Location: Burlington, WI
Posts: 797
Likes: 0
Received 0 Likes on 0 Posts
Default

sounds like the trans is junk
Old 05-02-2012, 06:41 PM
  #12  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
jasonz28camaro's Avatar
 
Join Date: Sep 2006
Location: Houston
Posts: 593
Received 7 Likes on 7 Posts

Default

Originally Posted by tricked94camaro
sounds like the trans is junk
Trans better not be junk after what I payed lol.

It ended up being the connector to the VSS. The multimeter and tech II did the trick.

I'm waiting on a new pigtail to come in the mail big you don't here back from me then it worked.

Thanks for all the help!
Old 09-28-2012, 07:14 AM
  #13  
TECH Fanatic
iTrader: (14)
 
mcalus's Avatar
 
Join Date: Nov 2007
Location: Chelsea, Michigan
Posts: 1,929
Likes: 0
Received 1 Like on 1 Post

Default

Where did you get the pig tail? I'm having the same issue but dont know if it's my vss or the wire.
Old 09-28-2012, 07:16 AM
  #14  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
jasonz28camaro's Avatar
 
Join Date: Sep 2006
Location: Houston
Posts: 593
Received 7 Likes on 7 Posts

Default

eBay. I have a brand new vss too if you need it.



Quick Reply: Transmission / Speedometer Problems



All times are GMT -5. The time now is 11:48 AM.