Alright - i'm waiting on a mechanical speed sensor for my t-5 after i swapped it in, so i keep getting a code 24 (vehicle speed sensor) and i thought that it was ignorable and didn't affect the motor. But since i changed it in i noticed that the motor misses when i accelerate (in 3rd or 4th gear) when its not above 2500 rpm or so. If i put too much of a load on it, it hesitates - the more i punch it, the worse. The car is driveable but really annoying - any input? I had a 8746 with a custom chip plugged in and it made it WAY worse - i threw in the old 8062 computer and it went away for a little while - does the speed sensor affect the timing/fuel curves???


Tyler

 

nope... i dont think it has any effect ont he motor, just makes the computer angry because it has no signal from it.

 

Well, I'm not sure what to think - all i know is that when the motor is under a load it skips around 2000-2500 rpm. Tomorrow i'mna look and see if i have a vacuum leak - i accidentally busted the check valve T-piece thats near the distributor (one line of it runs to the cruise can) and replaced it with just a regular T-fitting, so maybe theres a leak with either the fitting or the lines. I'm also getting a code 43 I believe - which mentions a "electronic spark control" problem - either a bad ESC module, knock sensor, ect. Could any of this be it? I also switched my tranny to a T-5 from an automatic lately - could I have missed something??

TYler

 

Try disconnecting the battery for 30 seconds. When my VSS was disconnected, it spit out a code 43, not 24. So make sure there is a signal from the VSS to the computer. The fact that you switched to a manual tranny shouldn't be a problem, but it might be pissing the computer off if you still have the auto chip in there, as it's trying to lock up the torque converter. As far as I know, that shouldn't be a problem though

 

I thought that the computer took readings from the speed sensor to work on fuel delivery and spark and stuff, but I could be way off on that.

 

well thats what i'm thinking. Right now the car runs like a total piece of crap - it misses if i roll the throttle on with ANY authority from basically any rpm. I'm going to replace my spark plugs and work on getting the speed sensor because i cannot figure out what the hell is making the car drive like a piece of ****

Tyler

 

Im pretty sure the computer uses map, tps, and rpms to calculate the advance and meter fuel. The vss mainly comes into play for i think tcc lockup and when you try to close in on that 110 mph mark and the computer governes the engine.

 

the vss can most definately make the engine run bad. i used to run the vss bypass switch and it would defeat the speed limiter. the drawback was when the vss doesnt see a signal it just pours in fuel to make sure the car is still running. as soon as i would flip the switch the car would die for about 1.5 seconds then it would rev back up and run as rich as hell until i reset the switch and it had time to see a reference signal.

jptaylor