Idle linkage rod and tps adjustment.

[Smokey77]

This is on a 92 940 regina car.
So I made the mistake of messing with the idle linkage rod thinking that that is where I adjust the idle, I wanted to bump up the idle in order to prevent it from stalling whenever I came to a stop, only to see the idle adjustment screw right in behind it. Now here is my problem, when I first start the car it idles low, put it in gear and it wants to stall but will stay running at pretty much below 100rpm. Not good. Put it back into park and tap the gas to get it back running, now it idles around 1000rpm with the ac on. Turn off the ac and it surges between 1300 and 2000. Clearly I messed up big time here. I set it to a point where it is driveable. I see there is a way to adjust it, but it is a writeup for an LH/Bosch system. Not sure if it is any different for the regina cars or not.

Upside is that I don't stall when I pull to a stop anymore. Downside is I am ready to drive this thing off a cliff, especially when mechanics down here apparently don't know how to mess with OBD1 cars.

 

[MasterBlaster]

First, make sure the throttle plate and bore aren't covered with goo, which will retrict the air flow even when the settings are "right".



Probably the procedure you already saw, but...

Shortened version:

1 - Disconnnect link rod from throttle arm.
2 - Loosen lock nut and adjuster screw, and let throttle plate close. (Might need to loosen TPS switch to let it move all the way closed).
3 - Tighten adjuster screw until it just touches the arm, then 1/4 turn more. Tighten lock nut.
4 - Readjust TPS switch so it clicks just as the throttle is starting to open. (When it clicks on closing, that's what tells the computer to activate the IAC valve and maintain the correct idle speed. If your TPS switch is still not working properly, it's going to be very difficult to get a consistent idle speed when the temperature or engine load changes)
5 - Adjust the throttle and kickdown cables per your writeup, then reconnect the link rod.
6 - 1.0 mm (.04") feeler on top, should give 0.1 mm (.004") gap at idle screw. Adjust link rod as needed.

 

[Smokey77]

First, make sure the throttle plate and bore aren't covered with goo, which will retrict the air flow even when the settings are "right".

View attachment 27770

Probably the procedure you already saw, but...

Shortened version:

1 - Disconnnect link rod from throttle arm.
2 - Loosen lock nut and adjuster screw, and let throttle plate close. (Might need to loosen TPS switch to let it move all the way closed).
3 - Tighten adjuster screw until it just touches the arm, then 1/4 turn more. Tighten lock nut.
4 - Readjust TPS switch so it clicks just as the throttle is starting to open. (When it clicks on closing, that's what tells the computer to activate the IAC valve and maintain the correct idle speed. If your TPS switch is still not working properly, it's going to be very difficult to get a consistent idle speed when the temperature or engine load changes)
5 - Adjust the throttle and kickdown cables per your writeup, then reconnect the link rod.
6 - 1.0 mm (.04") feeler on top, should give 0.1 mm (.004") gap at idle screw. Adjust link rod as needed.


View attachment 27771

Probably the procedure you already saw, but...

There are some measurement differences. The writeup I found wanted me to put 2.5mm of feeler gauge between the drum and stopper instead. All my tools are at work so looks like I will have to buy an allen set for the TPS. Thanks lots!

 

[Smokey77]

Adjust the throttle and kickdown cables per your writeup, then reconnect the link rod.

Also about this. Do you mean to remove slack? Not exactly sure what you mean by "per your writeup"

 

[Khrrck]

not sure regina TPS clicks. you should probably test it with a multimeter as per your previous thread when adjusting

 

[chronicrhythm]

not sure regina TPS clicks. you should probably test it with a multimeter as per your previous thread when adjusting

It clicks right as you start turning it

 

[chronicrhythm]

This is on a 92 940 regina car.
So I made the mistake of messing with the idle linkage rod thinking that that is where I adjust the idle, I wanted to bump up the idle in order to prevent it from stalling whenever I came to a stop, only to see the idle adjustment screw right in behind it. Now here is my problem, when I first start the car it idles low, put it in gear and it wants to stall but will stay running at pretty much below 100rpm. Not good. Put it back into park and tap the gas to get it back running, now it idles around 1000rpm with the ac on. Turn off the ac and it surges between 1300 and 2000. Clearly I messed up big time here. I set it to a point where it is driveable. I see there is a way to adjust it, but it is a writeup for an LH/Bosch system. Not sure if it is any different for the regina cars or not.

Upside is that I don't stall when I pull to a stop anymore. Downside is I am ready to drive this thing off a cliff, especially when mechanics down here apparently don't know how to mess with OBD1 cars.

What are the actual symptoms you’re having? A little tough to follow since you have several threads. If I remember right you had bad 02 sensor wiring or it was not plugged in. What have you done to the car so far? If the idle is surging your IAC is probably bad. Mine is bad currently but it doesn’t die so you have another issue. Have you looked for air leaks? What parts have you replaced. I’ve offered several times but I have the green books for Regina. You can test a lot of things like the TPS through the OBD1 diagnostic to see if it registers the idle position and then full throttle position.
From just dealing with a Regina 740 with a no start and it was driving me mad I would HIGHLY recommend getting a multimeter. Check the simple things like the resistance of intake air temp sensor, the MAP sensor (also check the vacuum like to it), 02 sensor voltage, engine coolant temp sensor (tricky to get to but can be done at the computers just be careful do not unplug computers if battery is in). It sounds like you have fuel, spark and air but to me if it’s hunting for idle you have a component out or an air leak. Have you looked at the flap on the air box that is for getting warm exhaust air? The thermostat goes bad on those and can cook your air intake temp sensor. Send me a PM with email address and I will send Greenbooks

 

[Smokey77]

not sure regina TPS clicks. you should probably test it with a multimeter as per your previous thread when adjusting

It clicks

 

[Smokey77]

What are the actual symptoms you’re having? A little tough to follow since you have several threads. If I remember right you had bad 02 sensor wiring or it was not plugged in. What have you done to the car so far? If the idle is surging your IAC is probably bad. Mine is bad currently but it doesn’t die so you have another issue. Have you looked for air leaks? What parts have you replaced. I’ve offered several times but I have the green books for Regina. You can test a lot of things like the TPS through the OBD1 diagnostic to see if it registers the idle position and then full throttle position.
From just dealing with a Regina 740 with a no start and it was driving me mad I would HIGHLY recommend getting a multimeter. Check the simple things like the resistance of intake air temp sensor, the MAP sensor (also check the vacuum like to it), 02 sensor voltage, engine coolant temp sensor (tricky to get to but can be done at the computers just be careful do not unplug computers if battery is in). It sounds like you have fuel, spark and air but to me if it’s hunting for idle you have a component out or an air leak. Have you looked at the flap on the air box that is for getting warm exhaust air? The thermostat goes bad on those and can cook your air intake temp sensor. Send me a PM with email address and I will send Greenbooks

Those are the current symptoms that I sent after I messed with the idle linkage rod. It was nowhere near as bad before. Before it would slightly bounce in rpm when cold with the odd occasion of revving high and dying back down and nearly stalling. Very poor acceleration in low RPM after I installed the 02 sensor, especially after bogging down a little bit after I come to a stop, but for the most part the fuel smell went away. The IAC was replaced at most a year ago, but I don't know when. The air leaks I spotted was mostly at the dip stick, I can't find anywhere about where to find the proper seals for it so I kind of grabbed some and put it on. Next to the throttle body intake is a very minor leak, I am not sure how to fix it other than finding replacement pipe. And where the intake temp sensor it is another minor leak. All of the vacuum lines don't seem to have leaks. But for now I am adjusting the idle linkage rod to try and get it back to where it was.

 

[2manyturbos]

Upside is that I don't stall when I pull to a stop anymore. Downside is I am ready to drive this thing off a cliff, especially when mechanics down here apparently don't know how to mess with OBD1 cars.

That is true all over. Technicians are not really taught how to work on cars anymore. They are taught how to hook up a diagnostic device to the vehicle and perform the repair/replacement according to what codes are returned. Your car can't be hooked up to a diagnostic scanner. The mechanics/techs have no idea what to do with it. If you are going to continue to own this car you are going to have to learn to work on it yourself. That's the bottom line.

 

[Smokey77]

That is true all over. Technicians are not really taught how to work on cars anymore. They are taught how to hook up a diagnostic device to the vehicle and perform the repair/replacement according to what codes are returned. Your car can't be hooked up to a diagnostic scanner. The mechanics/techs have no idea what to do with it. If you are going to continue to own this car you are going to have to learn to work on it yourself. That's the bottom line.

Yup. 100%. The Mr2 I have no problem with figuring things out on. Not sure why the volvo is more difficult to understand.

 

[MasterBlaster]

Also about this. Do you mean to remove slack?

It was the parts not really needed for idle speed adjustment, so not included
I assumed you already saw it in the "writeup for an LH/Bosch system" you have.

Not exactly sure what you mean by "per your writeup"

I see there is a way to adjust it, but it is a writeup for an LH/Bosch system.

 

[Smokey77]

It was the parts not really needed for idle speed adjustment, so not included
I assumed you already saw it in the "writeup for an LH/Bosch system" you have.


View attachment 27794

Ah I see. Thanks!

 

[Smokey77]

First, make sure the throttle plate and bore aren't covered with goo, which will retrict the air flow even when the settings are "right".

View attachment 27770

Probably the procedure you already saw, but...

Shortened version:

1 - Disconnnect link rod from throttle arm.
2 - Loosen lock nut and adjuster screw, and let throttle plate close. (Might need to loosen TPS switch to let it move all the way closed).
3 - Tighten adjuster screw until it just touches the arm, then 1/4 turn more. Tighten lock nut.
4 - Readjust TPS switch so it clicks just as the throttle is starting to open. (When it clicks on closing, that's what tells the computer to activate the IAC valve and maintain the correct idle speed. If your TPS switch is still not working properly, it's going to be very difficult to get a consistent idle speed when the temperature or engine load changes)
5 - Adjust the throttle and kickdown cables per your writeup, then reconnect the link rod.
6 - 1.0 mm (.04") feeler on top, should give 0.1 mm (.004") gap at idle screw. Adjust link rod as needed.


View attachment 27771

This saved me so much time!!! This is wayyy better than the other explanation, thank you so much! I just have to bump up my idle a slight bit. When I start the car it idles super low and stalls, I just tap the throttle and it idles like it did before. Is it possible that the IAC valve is staying closed until I blip the throttle? And when I come to a stop it stalls, just more often than it did before.

 

[Smokey77]

(When it clicks on closing, that's what tells the computer to activate the IAC valve and maintain the correct idle speed. If your TPS switch is still not working properly, it's going to be very difficult to get a consistent idle speed when the temperature or engine load changes)

Re reading this, is it possible that the IAC will stay closed completely when I initially start the car? Because when I start the car it idles a little bit low (maybe about 600rpm) as soon as the AC comes on it idles super low (Maybe 500 or less rpm) to the point where it struggles to stay running and then dies, if I blip throttle it is ok. Put in gear (with AC on). (the idle load changes) same thing, wants to stall out and die (100 rpm or lower). Once I blip the throttle (clicks the TPS when open and then obviously when closing) and it is totally fine. Back into park or neutral, idle is ok, Squeeze the IAC hose closed and release, it stalls the EXACT same way. Once I get it to idle with the AC on normally, and I turn the AC back off, it idles about 900-1100 RPM. A bit high, but comparing to my Mr2, when I turn the AC on on the Mr2, the idle increases. Which is backwards. And I know the Mr2 inside out and know it is in perfect shape. That is with no load on it obviously because it is in neutral.

 

[Smokey77]

Re reading this, is it possible that the IAC will stay closed completely when I initially start the car? Because when I start the car it idles a little bit low (maybe about 600rpm) as soon as the AC comes on it idles super low (Maybe 500 or less rpm) to the point where it struggles to stay running and then dies, if I blip throttle it is ok. Put in gear (with AC on). (the idle load changes) same thing, wants to stall out and die (100 rpm or lower). Once I blip the throttle (clicks the TPS when open and then obviously when closing) and it is totally fine. Back into park or neutral, idle is ok, Squeeze the IAC hose closed and release, it stalls the EXACT same way. Once I get it to idle with the AC on normally, and I turn the AC back off, it idles about 900-1100 RPM. A bit high, but comparing to my Mr2, when I turn the AC on on the Mr2, the idle increases. Which is backwards. And I know the Mr2 inside out and know it is in perfect shape. That is with no load on it obviously because it is in neutral.

Also, is it possible that I just have to have the tps adjusted BANG ON so that when I do start the car it clicks the TPS right away (Basically right once the barrel moves the slightest bit and still appears to be on the stopper)? Maybe I have it set a bit too far off which is causing this problem.

 

[2manyturbos]

You are not understanding the TPS adjustment. The click happens when the contacts open creating an open circuit. The contacts should be closed when the throttle is closed telling the ECU that the car is at idle.

 

[Smokey77]

You are not understanding the TPS adjustment. The click happens when the contacts open creating an open circuit. The contacts should be closed when the throttle is closed telling the ECU that the car is at idle.

Wasn't sure with his wording. That does make sense considering when I was reading the voltage, at close I had voltage, and between that an wot it was 0, and at wot it had voltage.