I searched and all i could find was someone who had what seemed to be tach lag. It wasnt that bad but that is not my problem. I want to know if anyone knows if it is normal to have what I would call a bouncing tach. I went out to cali speedway this last saturday and when ever I shifted and the rpm droped from switching gears, it would bounce. so if the rpm was suppose to be at 5000, when I shifted it would hit 5000 then with in 1 second go to 4,700 and up to 5300 then move back to 5000 and continue to rise like normal. Is this normal. I can try to to make a video if no one understands what I'm saying.
Thanks

 

sounds like a vacuum leak.

 

vacuum leak? so should i be checking vacume lines for a leak or is it an internal thing. Will it cause a loss in performance? Im not sure what to look for. The engine is new since it was put in because the last one burned oil, could the vacume leak have anything to do with the seals not set yet in the engine from it being new. I just really have to avoid the dealership. I've already taken the body kit and test pipes off 3 times in the last 6 months and it is a pain.
Thanks

 

you need to calm down lol. is it bouncing at idle or only while shifting?

 

sounds like the needle may be freezing

 

A vacuum leak probably wouldn't affect the RPM's way up in the 5K range. Can you hear/feel the engine's RPM changing with the needle, or is it just the needle moving?

A video would probably help.

 

lol, yea im freaking out. No, J/k I am just getting tired of all the little things that may/may not be wrong with a brand new car. I will try to make a video tommrow. And the idel is fine, the rev is fine it is just when i shift for example in my escort, i shift and the rpm drops from 4000 to 3000 and tack stays there and moves up, but the z especially at WOT will drop to the right rpm but flux immedately from 5000 to 4700 and up to 5300 with in a second. itls like the needle is trying to balance a weight on both sides if you can picture that. Everything works fine engine wise just bugs me that the needle fluxes so much at shifts.

 

The tach is controlled through the CAN bus. It's all electronic. What has vacuum got to do with it? Take it in to the dealer. They need to check wiring, harnesses, ground points...

 

let me know if you cant see it, i accidently put it as my clips and not public on the site.
http://video.cardomain.com/Clip.aspx...C1A499AF9BCDE3

 

yep you got a sloppy needle right there! I would recommend taking it in to the dealer and see if they will swap out the gauge cluster. Just a guess, but it's probably an electromechanical fault that's going to be tough to fix.

 

do you think just resetting the ecu would do anything. I hasnt always been like this. Or would even haveing the test pipes do this. I was thinking maybe the back pressure not being there like when it was stock with the cats could make it bump like that.

 

It's your turbonator causing a flux in barometric pressure

 

i cant believe i didn't think of that. it was. so i just decreased the pressure in the turbonator flux capacator and readjusted the flux curve and that solved everything. thanks for the great advice!

 

The only thing I think you could check on your own is the ground point for the gauge cluster. I believe it's in the FSM.

 

Hey no problem

 

Or maybe you're not shifting very smoothly, so when you shift... The engine speed may bounce a little while it's catching up or equalizing to the transmission speed. Do you feel a slight "bouncing" when you shift?

 

^^^^

I have the same problem in my car and there is no bouncing when I shift. Its as if the needle is loose.

 

maybe it does bounce because if i shift slow and let the clutch out slow it usually doesnt do it or if it does hardly, the harder i push the car (wot and shifting) the harder it bounces. as i stated above i almost want to think it has something in part with the test pipes but no one else has this problem becuase i though a tune would help the coj general has the same probmen with a lot more parts than me and a tune.

 

You stare at your tach that much at the track? I just glance at it to see if I'm slower or faster at a given point on the track each lap.

 

I think I have the same problem. In my case I'm pretty sure it's the clutch. I had some pretty serious problems with the clutch sticking awhile ago and my clutch has felt like **** ever since. Now when I try to drive it hard I get a bounce so to speak.