Hi everyone,The speedometer needle of my Evo 9 jumps to high speeds when I accelerate under full boost. (it jumps from 70 to140 then 180).Even the tachometer increase dramatically when this happens.If I accelerate in a normal way the needle functions properly and accurately.I checked and cleaned the vehicle speed sensor connector and pins --- still the same problem occurs .I repeat this only happens on rough acceleration =High boost.Did anyone had a similar case ?Do you have any suggestions ?Thanks

 

Probably just reading the correct speed.

 

All I heard was you got your evo going 180. nice.

 

I am guessing KPH?

Could it be a traction issue? What kind of power are you making?

 

Maybe the previous owner took the needles off to install some gauge overlay and didnt put them on correctly, or has this been your car the whole time?

 

Wow that is a lot of wheel-spins. Got pictures of your bald tires? :}

 

Thats one fast evo! mod list?

 

Verrry Funny guys

I've just bought the car from one month it's EDM so KPH.
It's not a traction, it's an indication issue.
The car has around ( not dynoed yet after the last mapping) 350Whp equipped with Full BBK turbo + M2 cosworth cams , peak boost 26 psi.
At the moment of defect the indication is incoherent with the vehicle speed - the speedometer goes up to 180 then comes down to 90 and so on, even the odometer travels distances with it (which makes conclude that it's not an instrument cluster issue).
What is weird is that If I accelerate gradually it functions properly I tried it several times even till high speeds (around 190 Kph)
The problem only happens on full boost (pedal to the metal)
A serious help is much appreciated

Cheers

 

This just a shot in the dark but I know of people who have had an issue with the temperature gauge reading intermittently high and the cause was a bad ground on the engine, in particular the ground cable behind the intake manifold. So, maybe, just maybe, the motor mounts are a little loose and the engine is yanking on the ground or possibly other wiring.

 

You say the tachometer also increases, does the actual RPM of the engine increase as well? Can you hear it?

 

I see where you're going and I take back what I wrote. It sounds like clutch to me.

 

That's what I thought at first but that shouldn't affect the speedo, I'm kind of leaning towards the transfer case (e.g. something slipping after the transmission). Not sure what specifically, given I have not yet looked into how our TC (along with the ACD) work.

 

Crazy glue on the needle so it doesn't slip if it's not your clutch.....

 

Got ur fix. Had a civic with the exact issue. Not sure if works the same but on the civic the speed sensor has three prongs in the harness end. My middle one was corroded and caused it to go crazy only under wot tho. I actually used a piece of scrap metal to make a new prong for it and never had another issue out of it.

 

Also forgot to mention that the pin seemed to look fine until I pulled it out. The problem was on the inside of the sensor plug.