Trueno102

iTrader: (1)

Hi, i removed my throttle body from my 91 N/A manual transmission, but im a bit lost since my throttle body looks different compared to the ones ive seen on the forum and the owners manual, here are some pics, the first pic is the throttle body but i didnt find throttle position sensor, so is it that cable i have to test instead
in this pic i tried to adjust the fast idle bc it was not aligned with the lines but which one should i tighten , should i tighten the left screw or the right one,
plz help me out, thanks

satch

iTrader: (1)

In the first pic at the bottom front which has the two black plastic pistons is the TPS.

In the second pic the screw that touches the metal piston is adjusted so the cam is in proper position relative to the roll pin which usually has a green painted dot on it. The other adjustment screw is to set the actual idle speed of the fast idle. Pour a pot of boiling water over the top of the thermowax and watch and see if the cam rolls completely off the roll pin. If not then immediately adjust the cam adjustment screw.

Review the pics in the following thread link. https://www.rx7club.com/showthread.p...dle+cam&page=4

Trueno102

iTrader: (1)

Thanks satch
i found a link that might help me out https://www.rx7club.com/2nd-generation-specific-1986-1992-17/tps-testing-gone-bad-726992/page2/, but im still very confused
if you scroll down it shows a diagram of the s5 tps and how to test it with a volt meter, and if i were to test it cold does that mean i have to unscrew the fast idle cam to the point that the cam roller isn't touching the fast idle cam, if so then when i check narrow range A-B its in spec, but E-D isn't in spec its at 119.8 closed and 8.25 full throttle

satch

iTrader: (1)

I'm not sure if you could set the TPS while the throttle body is removed from the car or the benefit in doing so.

EDIT: The link you provided indicates a test for the TPS to see if it is "within spec" which is different than "setting" the TPS. Testing it can be done with the TPS removed from the throttle body.

Trueno102

iTrader: (1)

Okay i see, well seems like its pretty close to spec Plus it also says not to adjust bc of the auto adjust system in the engine control unit. So it would be better for me to reinstall it and warm it up then adjust it

satch

iTrader: (1)

Adjust the narrow range of the TPS to 1 volt when the engine is thoroughly warmed up. Use the Green/Red wire of the TPS to achieve this. If after adjustment the idle is not close to the 750-800 rpm range then readjust the primary throttle plates via the set screw on the back of the throttle housing (screw closest to your left thumb in the second picture) then readjust the TPS to 1 volt again.

Trueno102

iTrader: (1)

okay after warm up i do the A-B check again and adjust till i get 1.00, what about the air adjust thing on top of the throttle body should i touch that or leave it alone

satch

iTrader: (1)

It depends. Try to get things running properly regarding the adjustments already mentioned and see how the idle behaves. If you're planning on idling the car to warm it up it will take a long time to fully warm up before the TPS can be set. How long should you wait? Watch the tach and see if it continues to drop as it idles and when it stops dropping make sure it is at an appropriate level and then wait another 5 to 10 minutes. When you set the TPS it's okay to do it with the car running, just be careful of Mr. Fan Blade. After the TPS is set to 1 volt let the car idle for another 5 minutes or so and check the reading once again to see if it stayed the same or dropped some. If it drops some then that tells you basically that you didn't wait long enough to set the TPS so just reset it back to 1 volt and wait for another 5 minutes and see if it holds or not and repeat again if it doesn't. The fast idle should be at about 1200 to 1500 rpm before slowly dropping to under 1000. 800 rpm or so is optimal when fully warmed up in neutral but this is somewhat dependent on any mods done to the engine.

Trueno102

iTrader: (1)

thanks alot satch it worked, the rpm is under 1k but when i started the car this morning it berally started and there was no warm up process which is kinda weird but it stayed under 1k rpm, im gonna still check on it to see if it stayed at 1volt, i put 4gallons of gas today im almost empty and ive only gotten 31 miles and i dont think thats good right, what else can i check bc thats bad millage

satch

iTrader: (1)

O2 sensor will hurt fuel economy if old and antiquated.

Trueno102

iTrader: (1)

I started the car again and it finally did the warm up process, but once it lower close to 1k rpm it kinda bogs up and down from 1k and 1,500rpm but once it warms up its at around 800rpm, so i still got to figure out whats up with that

satch

iTrader: (1)

Now would be the time to experiment with the idle adjust screw on top of the throttle body. Initial set coupler needs to be jumpered first before playing with the screw. You also might want to bypass the double throttle diaphragm by disconnecting its hose and securely plugging up either end as over time these units tend to leak during the warm up period.

Trueno102

iTrader: (1)

tried to adjust the top screw today and hope it gets better, the Initial set coupler is the green cable and i have to jumper it to the negative right, i did that and it kinda got smoother but hope it gets better. Today i drove the car till it shut itself off and i had 4gallons of gas since Thursday and at the end i drove 50miles which is still not so good, i averaged about 12.5miles per gallon and now im gonna have to figure out what could be causing me to get lower miles

satch

iTrader: (1)

Again, a properly working Oxygen sensor helps to prevent poor fuel mileage among other things.