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Posted by: saigon71 Nov 24 2009, 03:17 PM

If I understand correctly, the knob on the ECU adjusts mixture. Which direction do you turn the knob to make it run richer or leaner?

I have read that the you should hear 20 clicks from the TPS from closed throttle to open throttle. I hear none - is my TPS faulty?

Thanks.
Bob

Posted by: SirAndy Nov 24 2009, 03:40 PM

QUOTE(saigon71 @ Nov 24 2009, 01:17 PM)

If I understand correctly, the knob on the ECU adjusts mixture. Which direction do you turn the knob to make it run richer or leaner?

I have read that the you should hear 20 clicks from the TPS from closed throttle to open throttle. I hear none - is my TPS faulty?

The TPS only has a few contacts, can't remember how many, but much less than 20. More like 5 clicks, if you can even hear them.

http://www.pelicanparts.com/techarticles/914_cooley/throttle_position_calibrate_20.jpg

http://members.rennlist.com/pbanders/djetparts.htm

The ECU knob is only for the IDLE mixture ...

Andy

Posted by: SirAndy Nov 24 2009, 03:44 PM

I guess i was wrong. If you count the on/off individually, you may get 20 "clicks".

I still don't think you can hear those clicking unless you have the TPS open and next to your ear.
popcorn[1].gif Andy

Attached image(s)

Posted by: Spoke Nov 24 2009, 03:52 PM

Yes you should hear clicks. The clicks are the fuel injectors opening and closing as the throttle is opened. It's the FI's way of doing an acceleration pump like carbs. Do this with the engine off obviously.

If you don't hear the clicks, something is wrong. Not necessarily the TPS but it is a good place to start. You can test the TPS with an ohm meter.

Posted by: SirAndy Nov 24 2009, 04:01 PM

QUOTE(Spoke @ Nov 24 2009, 01:52 PM)

Yes you should hear clicks. The clicks are the fuel injectors opening and closing as the throttle is opened. It's the FI's way of doing an acceleration pump like carbs. Do this with the engine off obviously.

If you don't hear the clicks, something is wrong. Not necessarily the TPS but it is a good place to start. You can test the TPS with an ohm meter.

Aha, so you hear the injectors clicking, not the TPS ...

Posted by: tod914 Nov 24 2009, 04:56 PM

The 20 clicks you hear will be from the injectors. Key on, slowly depress the pedal with steady pressure and you should hear them. You should also be able to set it up the TPS visually. Most by now will have a wear mark in the intial possition.

Posted by: tod914 Nov 24 2009, 04:58 PM

lol Andy, you replied quicker than I could respond.

Posted by: McMark Nov 24 2009, 05:04 PM

The knob only adjusts idle mixture. If your foot is on the throttle, that knob doesn't change anything. That being said, anti-clockwise is lean, clockwise is rich.

And, as mentioned, you'll only hear clicks if the key is in the on position and the engine is not running.

Posted by: saigon71 Nov 24 2009, 05:08 PM

QUOTE(SirAndy @ Nov 24 2009, 04:44 PM)

I guess i was wrong. If you count the on/off individually, you may get 20 "clicks".

I still don't think you can hear those clicking unless you have the TPS open and next to your ear.
popcorn[1].gif

Andy

Thanks for the clarification. I just pulled the cover off and checked. Looks good.

Bob

Posted by: saigon71 Nov 24 2009, 05:13 PM

QUOTE(McMark @ Nov 24 2009, 06:04 PM)