DCmina

Thanks Hailers!

Err, how can I say this...
Well my car idles at 5000 RPM and I think that it's because the throttle is jammed to the open position.
Could anyone tell me how to fix it?
Thanks!

ROSHX7

My friends TII did that, and it was the weirdess thing of all. One of his intercooler mounting BOLT fell off and went into around the TB linkages and jammed it there OPEN. Don't know if that helps you at all, but it might give you some clues...

DCmina

I removed the air intake duct and, when someone's depressing the gas pedal, the throttle valves do not move a bit.
The throttle valves are horizontals, are they supposed to be that way?

presetlimits

mine did the same and it was just because the dashpot adjusting bolt had fallen off

Mobius

the throttle plates open horizontally. They can only open one way. You have found the problem. Now what you need to do is figure out why they're jammed. check the linkege on the front side of the dynamic chamber. That side faces the radiator. And the linkage on the backside.

Oh! Maybe for some weird reason your cruise control cable is retracting or is retracted.

Take off the cruise control cable and see if that's it.

The cable is on the backside of the dynamic chamber facing the the transmission. Its in your haynes manual.

Or find the cruise control fuse and pull it.

Or find the cruise control unit and disconnect it.

Or run around the car yelling and screaming.

DCmina

My car doesn't have cruise control, is there still a cable?

Also, in the Haynes manual they say that the freeplay of the throttle cable is supposed to be between 0.04 to 0.12 (1 to 3 mm) of clearance. That's when you try to pull the cable sideway right?


Oh and what do the throttle valves look like when they are closed? Are they down?
Also, when I push the throttle valves down, there's a thingy outside next to is that moves too. Is that supposed to be connected to anything?

Thanks.

Mobius

No cruise control? Are you sure about that. Look anyway.

So your plates are open regardless of what the gas peddle does, right?

When the throttle is closed all plates are "closed" meaning that the plates rotate on an axis. Such that you cannot see the back of the dynamic chamber. There are three. Two minors at top and 1 big one on the bottem. There's also another two on top that act like secondaries but these aren't the problem, I don't think. Anyway, all the throttle linkage is springloaded. The plates (the ones in back) should always be relatively "closed" in relation to the gas peddle's position. If they're jammed you have some obstruction like a bolt. Or cable. Or evil gnome.

See page 115 of haynes manual. Its page 115 in mine.

Do you see where it says Thermo, Throttle Sensor and Delay Valve? The delay valve touches the secondary plates so to speak. Sometimes, these ones can be open regardless of gas peddle action. (don't ask me what they do exactly or what their real name is cause I donno yet) But the one that the throttle sensor touches, in the picture, is that big one I was talking about. The ones above that one, are the two minors. These are spring loaded and should allways return to closed when there's no gas peddle depression.

I wonder if you have, or we all have, a vaccum that contributes to the idle? I'll have to go mess with the extra throttle body I got in my garage.

Mobius

Whoops. Should read:

when the throttle is closed, all plates relating to the springloaded throttle linkage are closed.

Mobius

After messing arround with my extra throttle body, I noticed that the plates are all the same size. But in the picture, the bottem one is slightly bigger.

Whatever.

DCmina

I don't think my throttle valves are open after all. Are they supposed to look like that?

DCmina

oops

Mobius

Those plates in the front are the secondaries i was refereing to ealier. You might try to close them while the engine is running to see if that has an effect on it. Now, I can't see the back ones very well, but it looks like there's a brass colored circle, so, yeah- those ones should be closed when the throttle is closed.

When the engine is idling, at five thousand or whatever get out and look at the throttle valves. See if they are open alot, kinda of- or most weirdly-not at all. Then accelerate the engine manually with by moving the throttle manually with the hand and note what you observe.

Don't run it for too long without the air cleaner tube off.

HAILERS

Put it all back together. Have someone start the car. Now remember that screw that you set the TPS with. Well while the car is doing its 5000 rpm deal, lift that screw by its head in a UPWARD DIRECTION. When you do that, does the idle subside substantialy? It should. Write back before six central time, please.
Oh, pardon my ignorance. On the other post I asked how far it was b/t the really small idle stop screw and the rotating arm that would hit it if it could only could. Well I understand the way I figued it, that that distance was about .7 tenths of an inch. Is that correct or is it further?????????????
Hey, is there anyone out there in DC'S area that can drop by and give him a hand????? He's new to this car and could use some pointers, please.
By the way, good pictures there. Woulda been great if you could have gotten a straight shot into the throttle body. That big black duct only has a single clamp on the other end. Comes off fairly easy. Just a little wiggle.

HAILERS

Hey, wait a darn minute. I just looked again at your picture of the throttle body from the original post. There's something askew there. Those vacuum hose to the right of the TPS. Tell me. How many hose are there???? I just see two, and it looks like one hose is doubling back feeding right back into the body. Is that perception the real thing? There should be three NIPPLES on the throttle body, with three hose going to them. I only have 86 and 87 models and yours is a 88, but I don't think that changed. Does anybody know?
Dc, is that right? Only two hose and one is doubling back????????

DCmina

Is there supposed to be a hole in the round thingy?

DCmina

Are the secondary valves supposed to be open?
I tried to close them while the car was running but it doesn't change anything.



Also, if I take the air cleaner tube out the car doesn't wanna start.



I have a question though, how does the TPS work? When the car isn't running, is the "hook thingy" supposed to be pressing on the moving part of the TPS or not? Mine doesn't even push it a bit. If I press the TPS while the car the running, the idle lowers but it's inconsistent.

HAILERS

Yep. There is supposed to be a hole there. The hole should be just about 3/16 ths inch dia.
Yes, the TPS is supposed to be depressed when your foot is off the throttle. If the key is on, and its rigged properly, the voltage output on the green wire with a red stripe will be about one volt.
Trust me, the TPS's function is not to set the idle. Its purpose in life is to tell the ECU how far y0u have depressed the throttle so it can make adjustments to the switching and relief solenoids, determine you have let off the throttle so it can cut the fuel flow etc.
Back to your picture: You have two butterflys on the top and one on the bottom with the eighth inch hole in it. Now I really like your pictures, they are of good quality, but I can't determine 100 percent what I can see on the bottom butterfly. It appears that at the bottom of the lower butterfly, there is quite a gap there compared with the upper two. I can't say for sure because of the darkenes around the bottom, but the gap on that butterfly should be virtualy the same as the upper two. Can yu confirm that there is a large gap b/t the lower butterfly and the bore it sits in.???????????????????
Yeah. The car should not start without the large black duct connected up. Supposed to be that way.

DCmina

So when you press on the gas, does the hook thingy press on the TPS or does it release it?

So what do you think I should do?
Should I just give up and bring the car to a garage?
Thanks.

DCmina

Yes there's a gap of like 2 mm at the bottom of the bottom butterfly. Is it supposed to be fully closed?
Do you want me to take a closer pic?

HAILERS

The gap should be 0.014 or so. There is a catch to that though. The fast idle cam has to be release for it to be the 0.014. I'm ignorant. In inces how much is 2mm. Something like .075 inches?????? Maybe the shop is the way to go. Felix Wankel looks at your throttle and thinks its not open too wide, so I could be looking at it and be imagining things.
EDIT: Your question about the hook thing. When you step on the gas it should retreat away from the TPS plunger. With your foot off the gas, the hook thing should depress the TPS.

HAILERS

Well, lets say I was all wet about the throttle being stuck open. Can you take a picture of the drivers side of the engine. The area that would be interesting is teh area just behind where you put oil in. There is a round metal valve there with two large hoses coming out the top of the valve. Try to show where the hose are connected to. That the AIR BYPASS SOLENOID and maybe the hose are not routed to the right places. Another experiment would be for you to disconnect that valves electrical connector, and then start the car. That valve is the one that causes the 17 second high idle to 3000rpm . Maybe its stuck open. You've been taking good pictures. I'm gonna have to get a camera someday.

NZConvertible

Check the oil metering pump actuator rod, it links the TB and the pump. It can hook up on stuff if you're meesing around pulling things off and putting them back on. This happened to me. Luckily I noticed it before I drove it. It would be fine up to full throttle, then would hook up and not return.

DCmina

When the car isn't running, the hook almost doesn't touch the TPS. It only push it in about 1mm. So if I press the gas the hook releases but since it almost doesn't touch the TPS it doesb't do much. Is this normal?

Anyway, I just drove the car to the shop. $60 for them to find the problem.

Thanks to everyone that replied!

Mobius

LOL

Boy at that rate, we could have rebuilt your whole engine in 250 years
and 2 million posts.

Enjoy your seven.

HAILERS

No its not normal for the *hook* to not touch the tps plunger. Thats what leads me to think your throttle linkage is stuck open. That, and also the pictures of your lower primary throttle plate being shown cracked open. Its almost conclusive proof between the two that your throttle cable is too tight or something is jamming it. I have doubts about some other things , like the picture of the front of your throttle body where you should have three vac hoses in a row, but you have one vac hose and the other two nipples tied together with a single hose doubling back. That picture told me you have no vacuum source for the solenoids on the drivers side of the engine and the acv can't be working atall. I deliberatly did that to my car Sunday to see what would happen, and the poor devil cycled up and down and about thoroughly confused. Makes me wonder what other hoses are attached not quite right. Part of the learning process. Happens to everyone. Just have to dig in and gain experience. You seem to be working at it pretty good. Keep on hammering away.