Crazy idle. and dead tps?
10-25-01, 11:48 PM
#1
Dangerous Curves
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Crazy idle. and dead tps?
okay guys here goes...
A while ago me and my friend measure my tps to see what it was at with that electrical measuring thingy. (sorry for not being technical, i forget what things are called) Well we couldn't read it because our electrical thingy didn't go that low in one unit, or that high in another unit (sorry i forget the units) So we left it alone. Well we forgot to plug it back in. I would think that that would make a difference on how my car ran, But it never made a difference. I'm thinking this is a bad thing and maybe i need a new one. What do you guys think?
And since it seems that it isn't working could it be effecting my idle? I have a really funky idle. it changes and goes where it wants all the time. I know it will be higher when it's cold. but sometimes it is high and other times it's just above 500rpm and feels like it's going to stall. and it will do this when it's all warmed up and i just stop at a light. It does do the 3krpm start up though
I tried to adjust the idle and i used the jumper wire to set it in learn mode (again not technical i think) but it doesn't make a bit of difference. I know it could also be the thermowax, but haven't gotten to checking that yet, such a pain.
So let me know what you guys think. Sorry this is so long, thanks
-Jessica
A while ago me and my friend measure my tps to see what it was at with that electrical measuring thingy. (sorry for not being technical, i forget what things are called) Well we couldn't read it because our electrical thingy didn't go that low in one unit, or that high in another unit (sorry i forget the units) So we left it alone. Well we forgot to plug it back in. I would think that that would make a difference on how my car ran, But it never made a difference. I'm thinking this is a bad thing and maybe i need a new one. What do you guys think?
And since it seems that it isn't working could it be effecting my idle? I have a really funky idle. it changes and goes where it wants all the time. I know it will be higher when it's cold. but sometimes it is high and other times it's just above 500rpm and feels like it's going to stall. and it will do this when it's all warmed up and i just stop at a light. It does do the 3krpm start up though
I tried to adjust the idle and i used the jumper wire to set it in learn mode (again not technical i think) but it doesn't make a bit of difference. I know it could also be the thermowax, but haven't gotten to checking that yet, such a pain.
So let me know what you guys think. Sorry this is so long, thanks
-Jessica
10-26-01, 12:10 AM
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The TPS doesn't affect your idle.
Get a good voltmeter (the electrical thingy
), set it to resistance (that one unit 
), and test it like you were before.
Except this time, measure the resistance through the entire range of the throttle's motion. While touching it go from closed throttle to wide open throttle. If the numbers move from ~1.00 to ~4.00 or vice versa smoothly with no spikes in the resistance the TPS is fine.
I think the problem is in the thermovalve system. Easy way to band-aid that is to pull the throttle body and remove the spring to the fast idle cam, and then wire that linkage back so that it doesn't touch the fast idle cam roller. You don't actually have to remove the spring from the throttle body, just unhook it and leave it. Doing this will allow you to get an accurate TPS setting because as far as your throttle body knows it's always in a warm state, you will no longer have anything automatically adjusting the throttle plates.
You'll still have a 3000 RPM startup because there's a coolant temperature sensor at the bottom of the radiator that tells the ECU to add more fuel to the mixture when the coolant is cold, kind of like an automatic choke. If you have the thermovalve disconnected and it's cold out your car will hate you in the morning. When you start it it's gonna sputter and run like **** for a few seconds, but after it warms up a bit it'll be fine. As soon as that sensor detects that the coolant has reached normal temperature the ECU will respond accordingly and it will go back to normal by leaning the mixture out.
The reason the car will run like **** when cold is because it's getting too much fuel and not enough air since the thermovalve isn't opening the throttle to allow more air and fuel in to perfect the mixture that the ECU expects.
I hope this helps.
Get a good voltmeter (the electrical thingy
), set it to resistance (that one unit ), and test it like you were before.Except this time, measure the resistance through the entire range of the throttle's motion. While touching it go from closed throttle to wide open throttle. If the numbers move from ~1.00 to ~4.00 or vice versa smoothly with no spikes in the resistance the TPS is fine.
I think the problem is in the thermovalve system. Easy way to band-aid that is to pull the throttle body and remove the spring to the fast idle cam, and then wire that linkage back so that it doesn't touch the fast idle cam roller. You don't actually have to remove the spring from the throttle body, just unhook it and leave it. Doing this will allow you to get an accurate TPS setting because as far as your throttle body knows it's always in a warm state, you will no longer have anything automatically adjusting the throttle plates.
You'll still have a 3000 RPM startup because there's a coolant temperature sensor at the bottom of the radiator that tells the ECU to add more fuel to the mixture when the coolant is cold, kind of like an automatic choke. If you have the thermovalve disconnected and it's cold out your car will hate you in the morning. When you start it it's gonna sputter and run like **** for a few seconds, but after it warms up a bit it'll be fine. As soon as that sensor detects that the coolant has reached normal temperature the ECU will respond accordingly and it will go back to normal by leaning the mixture out.
The reason the car will run like **** when cold is because it's getting too much fuel and not enough air since the thermovalve isn't opening the throttle to allow more air and fuel in to perfect the mixture that the ECU expects.
I hope this helps.
Last edited by Mykl; 10-26-01 at 12:12 AM.
10-26-01, 12:14 AM
#3
mad scientist
Actually the TPS can affect idle, but not in the way her idle is messed up.
Have you checked your BAC valve? Try unplugging it and seeing how your car idles then.
Have you checked your BAC valve? Try unplugging it and seeing how your car idles then.
10-26-01, 12:28 AM
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Originally posted by mazdaspeed7
Actually the TPS can affect idle, but not in the way her idle is messed up.
Have you checked your BAC valve? Try unplugging it and seeing how your car idles then.
Actually the TPS can affect idle, but not in the way her idle is messed up.
Have you checked your BAC valve? Try unplugging it and seeing how your car idles then.
Are there any other ways the TPS can mess with the idle?
10-26-01, 01:00 AM
#5
mad scientist
Thats what I was thinking of, but if its bad, it can mess up the idle if its bad. Usually when peoples TPS's fail, their car runs like ****..wont idle, wont rev, etc.
