Double_J

iTrader: (28)

So the other day I had a bit of back firing and thought I would check out my TPS settings. They were pretty close but off none the less. So I adjusted it a hair and went out for a quick drive. When I got back home I noticed my settings were wrong again. I was pissed I thought I must not have tightened it enough but I had to get going so I parked the car and went in side.

The next day I came out to check the settings and they were with in spec again..... I took it out for a drive and again the settings went off. I repeated the above of checking the car before and after a drive, and each time the settings were correct when the car was cold but off when the car was hot.

While it sounds like my tps is shot I certainly hope not because I just sold a backup for a mere $20

milano maroon

iTrader: (1)

Is your fast idle cam working? If so you need to warm your car up, make sure the fast idle is disengaged and then set your TPS.

If your fast idle is working you will see a change in TPA voltage from cold to hot. Set it hot.

Double_J

iTrader: (28)

Yes it is working

milano maroon

iTrader: (1)

Try setting your TPS with your engine hot and after your fast idle has completely disengaged. Or put a spacer between the fast idle plunger and your linkage to ensure complete disengagement.

Do that and report back. Do the voltages vary now?

Double_J

iTrader: (28)

I tried it out, and now my TPS settings are correct once the car is warmed up. I still have the back firing problem but I am starting to think that is because of my throttle body mods. At low RPM's my afr gauge says 17. Guess once it is tuned I will know for sure.

Thanks for the help!!

milano maroon

iTrader: (1)

So it still backfires a little? I dealt with that situation recently myself and had a thread regarding setting the TPS. You might try one more step in setting your TPS. And that is, with the car hot and the fast idle disengaged what is the primary butterflies' position?

Here is a thread for you to look at:

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/fixed-my-idle-problems-backfiring-bucking-more-170731/

In the first post you'll see that Damian said to back off the Idle Adjustment Screw until it barely contacted the butterfly linkage. This should close the primaries and be your starting point. With the engine hot, do that, and then set your initial low range values for VTA1 and VTA2.

Then you can reset you Idle Adjustment Screw as before for proper idle. Note however, that your idle position values for VTA1 and VTA2 may or may not still be within range, but, the TPS is now correctly reporting to the ECU what it's position is. Mine remained in range by the way. Doing this eliminated a small backfire I was experiencing.

Let me know if this helps.

Double_J

iTrader: (28)

I did read that post. My screw is not touching it at all. Also turning the air screw doesn't change my idle in the slightest. Is that normal? Lol

milano maroon

iTrader: (1)

Maybe there are some other things which should be checked. Are you saying that you are idling with no pressure on the primary throttle linkage from the Idle Adjustment Screw? And closing the Idle Air Screw at the bottom of the throttle body doesn't slow the idle down?

If so you need to look at a throttle cable being too tight or perhaps an air leak. Something is allowing air in to support combustion.

linnadawg

iTrader: (14)

Check your dashpot and make sure its not stuck all the way in. It lets the throttle close gradually. I think it disengages the throttle at 2200rpms?

linnadawg

iTrader: (14)

Read the FSM on how to set the idle. You have to jump the check engine light while your setting it otherwise the ISC valve will continue to adjust your idle.