I am very. very grateful for the help I have recieved thus far, I am proud to be a member and if this works out, I'll help to $upport this forum. maybe when this is all wrapped up we can keep it as an example of a good thread. Thanks again to everyone, who has helped with advice, pics, explanations and most of all experience.

 

No hero on my part, just someone who has seen your videos and has enough determination to help you get it running right. What made this whole thread different is the fact that you used your head and gave us an audio and visual presentation of your problem, coupled with a willingness to listen to us and carry out our suggestions. Kudos to you for that. Once you have it fixed, you will have learned a great deal about your car and all of us gain satisfaction and refreshed knowledge from helping you.

Ok...in your current video, I hear some misfiring going on and it sounds a bit like an air/ fuel ratio problem. A couple of things to try:
Turn the a/f adjustment screw on the resistor pot one direction or another and see if the sputtering improves. You might indeed have a small vac leak. Or try my favorite approach with an unlit propane torch aimed at your air filter. Crack open the valve on the torch and if the sputtering goes away and the speed increases, it's too lean and you need to use the torch to search for leaks. If you have leaks, I would recommend fixing that before making your final adjustments to idle speed and tps.

 

By the way, before you set your tps, we want that gap between the screw (with the locknut) and the throttle lever to be zero. It should be touching it. I have pics of a throttle body that shows the fast idle cam, thermowax, dashpot etc. but I have to figure out how to edit and upload them from Photobucket. (you could say I'm pic illiterate haha.)

 

Here's a pic of the fast idle cam on the high step (cold thermowax)

 

Here's one with my thumb holding the fast idle cam off the roller (simulated hot thermowax)
As you can see, it would take a crapload of clockwise turns of the screw to move the cam off the roller, likely not enough thread to do so.

 

Naw. There's something still wrong IF it's idling at 1400rpm.

I look at your picture and where it says BAD GAP and I think that gap is indeed tooooo much for the throttle plates to be fully closed. I'm assuming that gap exists when you have already turned the SCREW all the way clockwise. IF so, then SOMETHING is holding the throttle plates open a touch causing this high idle. IDLE is approx 750rpm give or take some.

I scanned a throttle body with the throttle plates closed. See the gap?? Small to no gap. There are five or six threads of that small screw protruding. I think you have about the same amount of threads on your screw BUT a large gap.

Why is there a gap????? Something is holding the plates open. IT MIGHT be that round, somewhat gold damper item. See where I unscrewed mine and it is not on my throttle body in the jpg but is in yours???? Take a 17mm open end wrench and find the nut on the other side of the bracket that holds the damper on. Loosen the nut a turn or two, THEN unscrew the round damper and see if the GAP starts getting smaller. IF if does, then it was that round damper holding the plates open too much.

That's my thoughts on this. The 1400 rpm idle is TOOOOOO MUCH, TOOO HIGH. It should be approx 750rpm.

 

By the way, you might try something. IF the engine is idling and hot, then with your finger press against that TAB on this side of the GAP. Push inboard and listen to see if the idle gets lower. IF it does, that confirms the throttle plates are not fully closed.

And YES, you were turning the right screw to make the fast idle cam come off the roller and let the throttle plates go toward fully closed.

 

This shows the dashpot plunger (white).

 

You should be able to completely depress this plunger with some resistance. It should not be keeping the throttle lever from contacting the stop screw.

 

You said in post #5 that your palm pilot showed a coolant temp of 200 degrees, but I'm curious what the reading actually is at the thermowax housing. An infrared thermometer would be quite helpful, I think you can get one cheap at Harbor Freight, perhaps other tool suppliers. I noticed early on that your stock temp gauge was reading pretty low, I know they aren't always accurate, but it should be closer to the halfway mark. If the t-wax isn't seeing 180+ degrees, it's plunger might not be fully extended, keeping your throttle lever off the stop screw.

 

Well.............then take that into account. Easy to overcome. REMEMBER in you picture where you point towards a SCREW written in RED/??????????

IDle the engine, then take a finger and put it under the screw you have pointed to in RED and lift upwards. At the same time look at the GAP. The GAP should decrease as you lift up on the screw. Did that work for you ?????????????????

Probably gone to WORK for now. Later then.

 

This shows the actual fast idle speed screw (bottom screw, with spring).The one you were turning adjusts the position of the cam only. This screw sets the actual fast idle speed. You can turn this screw counterclockwise to slow it down, and re-adjust it to spec later.

 

If you open the throttle by hand, you can get to the speed screw easier (engine off, reduntant I know).

 

That's true and I should have mentioned that screw. The problem with the thermowax shown by Scrip7, is that the thermowax in that pictue is not hot therefore it is not all the way extended. Makes a difference. The more extension of the cylinder means the sooner the cam seperates from the roller.

 

um HAILERS is probably the most knowledgeable car person i've ever met

 

Exactly. That's why I was questioning the coolant temps in post #85. Wouldn't it be great if all of Greenbud's problems stemmed from a weak t-stat and out-of-range tps? He would be relieved of his funky idle with enough cash left over for a good Margarita.

 

Okay, I'm home from work now, and i see you guys have been busy...

I know my car isn't supposed to idel at 1400 but I feel like we're making progress.

So I have a question, Do I leave that screw turned all the way to the right for now? what about later? I'm assuming at some point we'll get to resetting it..

But yeah, that gap is present when the screw has been turned all the way to the right.

1)I will go and see if I can get that gap smaller, I'll loosen the dashpot and see if that helps. I'll pull up on that screw and see if it cahnges the gap as well.

2) I'll check for idle increase when propane is introduced via the air filter, if it increases I'll check for vac leaks w/ propane.

But what do you want me to do next? Should I just turn the actual fast idle speed screw counterclock wise for now?

I guess I'll try to set the TPS if the gap gets smaller. But at what point should I plug the bac back in or try to set my idle?Just tell me what to do and I'll do it to get this baby running right..

Thanks a million you guys. I'll post in a little while with my results of tonights experiments....

 

****1)I will go and see if I can get that gap smaller, I'll loosen the dashpot and see if that helps. I'll pull up on that screw and see if it cahnges the gap as well.
************************************************** ***************

I'd do that first. Hook your finger under the screw and push up. You'll see what I mean when you do it. Watch the gap. It should decrease. IF it does decrease and touch the small throttle stop screw (the one with the jam nut on it), then try adjusting the OTHER screw that SCRIP7 mentioned.

He didn't point an arrow at it, but if you'll look at the LAST PICUTE ABOVE THIS POST, you'll see a small screw close to a spring that is wound around a shaft. I forget which way to turn that one.

I'd leave the screw you already turned, full clockwise. The turn that other screw first one way then the other while watching the GAP. If one way makes the GAP smaller, then keep turning til you get it as small as possible. Then start the engine and see if the idle goes down.

If unsure about that OTHER screw................well tomorrow I can highlight it. Can't right now where I am.

I'm just real sure that GAP is wayyyyy to big. REmember how I mentioned above in another post how mine has but five/six threads protruding from the stop screw that has the jamnut????? How many has yours? I mean mine has five/six and is touching the TAB. YOU have a gap b/t the tab and the stop screw. Not good to me anyway.

 

couldn't get the gap any smaller, I'm gonna try turning that fast idle screw and the propane right now
hold on
it's pitch black out and the mosquitoes are killing me.

 

The stop screw with the jam nut was never intended from the factory to be touched at all. It is set to give just the right amount of clearance between the throttle plates and the bores, to create the "minimum air rate", the starting point with which the other idle devices are calibrated. There should be no need to mess with that adjustment at all.. The fast idle speed screw I mentioned will lower the speed if turned counterclockwise. If the idle drops down to 750ish when that screw is backed off, then it isn't the dashpot holding it open too far. It then will be the fault of the thermowax for one of 2 reasons:

(1) the thermowax isn't reaching normal operating temp to allow the plunger to fully extend, either because the thermostat is weak or there isn't sufficient coolant flow through the coolant hose or throttle body due to deposit buildup, or
(2) enough wax has leaked from the thermowax unit over time that it's plunger won't fully extend. This can happen, just like the wax in a thermostat's "pellet" can leak out and cause overheating. So, it makes the most sense to me to back off the fast idle speed screw first. You can always set it to spec once everything has been fixed.

 

okay so the screw was like this when i started it, the screw has a round bottom which is hard to see in the pic but it's very close to the tab now. i was just pushing around moving the throttle linkages around and pushed down on the theromo wax alittle bit, so this is where we are now.....

and it started up but this time only went up to like 1000 and stayed there for a second, then it started to drop down but with out a surge, it was smooth but floating, it would die if i didnt keep it alive by just barely hitting the gas pedal, the pedal feels like it isn't even there it's so easy...



so it's smooth but it came down significantly from 1400 or so, now it's too low i guess...

I have a vid if you want to see it of this new idle

 

That's good.

I'd go to that STOP scew and loosen its jamnut and turn the tiny screw til it barely touches the TAB.

Then you might go to the BAC and turn it's screw out a turn or two and get the idle back up to close to 750-800 rpm or so.

Do this with a HOT engine.

And put the TPS plug back on before you do that and see if it changes the idle much if any. Do this first if you have not already. Sorry about the slow responses, I'm busy. I don't know about others, but I'm doing stuff right now. I'll look in again later.

 

Go ahead and read post #85 and then #95. If the idle is too low with the throttle tab against the stop screw, remove the air intake hose and check for a buildup around the edges of the throttle plates and also the bores. All engines develop a film in this area that needs to be cleaned off every few years. This buildup causes low idles. Sometimes the BAC doesn't respond very quickly and the idle will dip down to, say, 500rpm and then back up to 750. I clean throttle bores almost every day where I work because of this. I use a pedal depressor to hold the throttle open while I clean the bores and plates with solvent and a brush. You could do just as well with a brick placed on the gas pedal, some carb spray and a toothbrush. Just don't forget to remove the brick before starting it up haha. I'm placing bets that you have a weak t-stat. Use a OEM mazda one and see what happens.

 

okay great, I'll adjust the stop screw right now.

the tps was already plugged in for the last one.

The BAC was unplugged for the last one, I'll connect it now and try to adjust idle to 750-800.

sounds good, I'll be back in a coupel minutes..

 

okay hold on i gotta read those posts too, i missed that