i noticed it after I did my j-pipe+exhaust, ...but didnt think much of it until recently.

I'm not entirely sure how to explain it, but here it goes...

1) it seems like my speedometer is DEFINTIELY not matching up to how fast my car is going...and i know there is a margin of error but a few days ago i got pulled over going 51 when like 10 min before I got pulled over i was sure the speedo read 40 on a 30 zone.

about a few hours later on the same day i get pulled over again, this time i was sure i'm going 70 on a 60 but i was clocked for 79.

(luckily both times the cops just gave me a break, and i didnt get ticketed...

yesterday, i got pulled over again, 45 on a 30 when my speedo was reading 35ish.


on top of that

2) i noticed that when i go WOT, my speeddo drops back down kind of oddly...
(i.e. - i'll accel to 80MPH...and when i let off on the gas, usually, your needle will decrease pretty steadily right? but of late, the needles "LOOKS" like it gets stuck or that it returns back to 0 in a very rough and jerk manner...that's the best way i can describe it. <in addition, alot of times when i accel, i get like this really sudden jerk in acceleration after i hit like the 30mph mark...and when i decel, i get this same "jerk" and that's when the speedo needle kinda seems stuck>


was wondering if anyone else has this issue or know's what's possibly going on.

this car as 21k miles on it...so i have absolutely no idea what could possibly be up.

 

well until you find out whats up-you may want to drive below the speed limit by the amount your learned are happening now
drive 25 in a 35 as example
There are specialist shops that only fix speedos and tachs- look in the phone book for one near you.
if there is an electronic connection for the speedo - I am guessing that the speedo runs off the wheel speed sensors
your not the first to have a prob- I heard of total failures on speedo and needed to order a part
Go to parts store that will pull the codes for you and report any back here

 

heh, yea after yesterday's ticket i quickly adjusted my speed well the speed that it was indicating vs. speed i may actually be going.

unfortunately all the specialist shops around here seem way too sketchy.....

see the odd thing is actually an hour after this post, i got kinda hungry ran down to the supermarket, and well...there was this nice long straight with no one around....i hit WOT and CEL flashed...pulled over, put it in P and N and hit the accel, no CEL...put it back in D, tried WOT...no CEL...went to market came back on same straightroad, no CEL... so now i'm really getting confused...

 

Sounds like it could be an intermittent problem with the VSS. The sensor could be going bad. If the car itself is driving fine other than just the difference in speedo information that sounds like the obvious place to start looking.

Your transmission has 2 sensors. the input shaft speed sensor and the output shaft speed sensor. If I am not mistaken the output shaft speed sensor is the actual sensor that provides the needed information to indicate speed on the speedo. That CEL could be that the ECM defects a difference in the input shaft speed sensor and the output shaft speed sensor and that threw your cel (meaning something is slipping in the transmission). Also I don't believe our cars has a stand alone VSS sensor but instead the VSS sensor is the output shaft speed sensor on the transmission.

But most likely its the sensor going bad or the related wiring. I suppose even an ECM problem could be it but doubtful. But first thing I would go do is see if the car has any stored codes that cause the CEL to come on. Even though its off now it may have left a code that needs to be checked by a scan too. Go by your local parts store and get them to scan it for free. Then come back and tell us what code you had.

D

 

https://acurazine.com/forums/showthread.php?t=173517

 

Don't know what the problem is but it sounds like a broken, fouled, un-plugged sensor of some sort.

Different than darksky's problem (IMHO) since your speedo seems to be WAY off and "jerky".

 

look at everything you worked on or near for accidental damage

 

thanks for the input, yea i'm gonna take it to the shop and get it hooked up to see if any CEL codes were stored.... in 2 weeks lol (in NY for a wedding T.T)


does anyone know if it's a fouled up sensor how much that would cost without warranty? sigh..my warranty for the baby finally expired about a month ago (can't believe i've had this car for 4 years)