High Idle

[ARK_SWAMP_RIDER]

My 88 pickup (22RE 5 speed) had recently developed a high idle problem. It idles fine at start up, and also idles fine when you let off the throttle IF the pedal was depressed 1/4 the way down or more. Anytime I press the gas pedal lightly then let it return to idle, it will idle very high. I can give it a quick press to rev the engine and idle will return to normal. It's just the base model so I don't have a tach, not sure on the actual RPM's. Anyone have any suggestions on what could be causing the issue or things to check for?

EDIT: There are 3 issues, all of which started after I hit a small curb. The hit was rough but wasn't anything bone jarring (I'd expect harder hits off road). I was pulling into a parking lot that was raised higher than the street, right after the hit the truck turned off. It started right back up, but since I've noticed several issues:

1. Throttle won't return when barley pushed. Pedal has to be pushed more than 1/4 to make the idle drop when released. I can see the throttle in the engine bay sticking, it does this even when pushing it by hand.

2. There's a clicking noise I hear at start up. As soon as I give it some gas the noise stops. It's been determined it's the Open Circuit Relay for the fuel pump that's clicking, but not sure what's causing it.

3. Truck randomly dies while driving. I drive about 10 miles a day, it's happened 2-3 times in the last week. It always happens when the clutch is pressed and I'm coasting.

I checked for trouble codes, and it's throwing code 51. I know there are issues with the A/C that I haven't addressed just yet, I'm thinking this could be related to the code (issues with the A/C switch).

 

[helo-mech]

Have you checked to see if you have the same issue when actually moving the throttle in the engine bay? Could be your cable is kinked and catching when barley engaged due to the limited amount of return force produced by the throttle spring. When you depress further you get more return force and it may be enough to get past a kink. I would manipulate the actually throttle and see if you still have the same issue.

 

[ARK_SWAMP_RIDER]

Have you checked to see if you have the same issue when actually moving the throttle in the engine bay? Could be your cable is kinked and catching when barley engaged due to the limited amount of return force produced by the throttle spring. When you depress further you get more return force and it may be enough to get past a kink. I would manipulate the actually throttle and see if you still have the same issue.

Will give that a try in just a bit, thanks!

 

[helo-mech]

Will give that a try in just a bit, thanks!

After that of course you are looking at things like air leaks in the intake, vacuum leaks, the TPS and EFI components. I can set you up a link for the FSM if you don't have it.

 

[ARK_SWAMP_RIDER]

After that of course you are looking at things like air leaks in the intake, vacuum leaks, the TPS and EFI components. I can set you up a link for the FSM if you don't have it.

I have the FSM....just new to all this and never used it before. I've done a few things like suspension installs, but typically haven't messed with mechanical stuff.

I'm not sure if it could be related, but I've had a few time where the truck has died while driving. First time I hit a curb pretty hard turning into a parking lot and it died. Since then, I've heard a clicking noise from around the passenger side door speaker and it'll die on occasion (happened 2-3 times in the last week). It always dies right after I hear the clicking. I don't really think it's related but though maybe worth mentioning.

 

[ARK_SWAMP_RIDER]

I just took a look at it......when pressing the pedal and letting off I can see the throttle hanging in the engine bay. When pressing the throttle by hand under the hood, it does the same thing. Will something like WD-40 or PB Blaster on the throttle help, or will the spring (or whole cable) need replaced?

As far as the clicking, it's coming from around the passenger side kick panel, don't think it's related. I'm about to pull the panel and see if I can find the source on that one.

Thanks!

 

[helo-mech]

I have the FSM....just new to all this and never used it before. I've done a few things like suspension installs, but typically haven't messed with mechanical stuff.

I'm not sure if it could be related, but I've had a few time where the truck has died while driving. First time I hit a curb pretty hard turning into a parking lot and it died. Since then, I've heard a clicking noise from around the passenger side door speaker and it'll die on occasion (happened 2-3 times in the last week). It always dies right after I hear the clicking. I don't really think it's related but though maybe worth mentioning.

This is where my craziness will come in. Something like hitting a curb and then having clicking and running issues makes me start thinking crazy stuff like you knocked a ground loose and you have a relay chattering. The ECU should be over there in the right kick panel, which would be near the pass speaker, but I don't know if there are any relays over there off the top of my head. Once you check it manually see if you can wiggle anything around in the right kick panel and duplicate the issue. The wiring in these things get brittle as heck over the years and it does not take much to get them to act up. Until proven wrong, I am betting that you knocked something loose.

As a matter of fact, take a real good look at you TPS connector. If that thing is misaligned or cattywhompus, yes that is a technical term, it will give the whole EFI fits.

 

[ARK_SWAMP_RIDER]

This is where my craziness will come in. Something like hitting a curb and then having clicking and running issues makes me start thinking crazy stuff like you knocked a ground loose and you have a relay chattering. The ECU should be over there in the right kick panel, which would be near the pass speaker, but I don't know if there are any relays over there off the top of my head. Once you check it manually see if you can wiggle anything around in the right kick panel and duplicate the issue. The wiring in these things get brittle as heck over the years and it does not take much to get them to act up. Until proven wrong, I am betting that you knocked something loose.

As a matter of fact, take a real good look at you TPS connector. If that thing is misaligned or cattywhompus, yes that is a technical term, it will give the whole EFI fits.

EDIT: should also mention the noise only occurs at idle, and mainly when the truck is first started (idle seems a touch lower when it's very first cranked).

I pulled the speaker grille and speaker, turns out there's a relay behind it. This is the source of the noise. Is this the TPS relay you're talking about:

 

[helo-mech]

EDIT: should also mention the noise only occurs at idle, and mainly when the truck is first started (idle seems a touch lower when it's very first cranked).

I pulled the speaker grille and speaker, turns out there's a relay behind it. This is the source of the noise. Is this the TPS relay you're talking about:

Me saying the ECU in the right kick panel is near the pass speaker just meant that it is over on the pass side. I wanted to clear that up in case anyone reads it and gets confused.

I'm not sure what relay that is, but you said it was behind the pass speaker right? You having the truck is little different than what I have dealt with. The TPS connector is on the throttle body. From what I understand, it would not have a relay. It simply sends the throttle position to the ECU for the proper air/fuel ratio.

Like I said I'm not sure what that relay is for, but relays are not really made to click back and forth to the point where you hear it. See if the FSM can tell you what that relay is and see if it is related to the EFI.

Have you checked it for codes? Even if the Check Engine Light is not on, it may have one stored.

 

[ARK_SWAMP_RIDER]

Me saying the ECU in the right kick panel is near the pass speaker just meant that it is over on the pass side. I wanted to clear that up in case anyone reads it and gets confused.

I'm not sure what relay that is, but you said it was behind the pass speaker right? You having the truck is little different than what I have dealt with. The TPS connector is on the throttle body. From what I understand, it would not have a relay. It simply sends the throttle position to the ECU for the proper air/fuel ratio.

Like I said I'm not sure what that relay is for, but relays are not really made to click back and forth to the point where you hear it. See if the FSM can tell you what that relay is and see if it is related to the EFI.

Have you checked it for codes? Even if the Check Engine Light is not on, it may have one stored.

I haven't checked for codes, don't know now (I'm used to newer rigs). I'll search and figure out how to check this and report back.

I removed the in dash speaker (to the right of the glove box) and that relay is just sitting behind it. It looks like a factory connector. I've never used the FSM, but I'll give it a shot and see what I can find.

Back to the original question, what is the solution for the sticking throttle? Wasn't sure if I could lube it up or if the spring and/or cable needed to be replaced.

Thank you for the help, it's greatly appreciated.

 

[helo-mech]

Looks like that is a Open Circuit Relay for the fuel pump to keep the pump from running when the ignition is on but the engine is off.

That should not be clicking as you go down the road. If that engages as you are driving down the road it would defiantly make it stumble and cut off.

 

[ARK_SWAMP_RIDER]

Looks like that is a Open Circuit Relay for the fuel pump to keep the pump from running when the ignition is on but the engine is off.

That should not be clicking as you go down the road. If that engages as you are driving down the road it would defiantly make it stumble and cut off.

It's only clicking at idle, mainly right when the truck is started. When even the slightest amount of throttle is applied, the clicking stops. Normally once throttle is applied I don't hear the clicking until next time the truck is started.

 

[ARK_SWAMP_RIDER]

Have you checked it for codes? Even if the Check Engine Light is not on, it may have one stored.

It's not throwing a CEL, but I checked for codes and got 51. Looked it up but it's only listed as switch signal, doesn't really tell me anything.

 

[helo-mech]

It's only clicking at idle, mainly right when the truck is started. When even the slightest amount of throttle is applied, the clicking stops. Normally once throttle is applied I don't hear the clicking until next time the truck is started.

If I understand right you've got a couple of things going here that may or may not be related.

1. Throttle won't return when barley pushed. Pedal has to be pushed more than 1/4 to make the idle drop when released. I would look at linkage and the throttle itself.

2. Clicking that you hear after start-up. Have you always heard this clicking or did this start after you hit the curb? If after, then I am wondering if you are just not hearing it click/engage when you are driving with the additional road/engine noise. Once it engages it would open the fuel pump circuit that results in the 3rd problem. Check for codes.

3. Truck dies as you driving. I think you have to figure out #2 first. Could be the relay, the wiring or loose connector. Then again it could be totally unrelated. I doubt it though. Check for codes.

Wish you were closer, I'd tell you come on over. I'd love to be able to climb into this on with a multimeter and the FSM.

 

[ARK_SWAMP_RIDER]

If I understand right you've got a couple of things going here that may or may not be related.

1. Throttle won't return when barley pushed. Pedal has to be pushed more than 1/4 to make the idle drop when released. I would look at linkage and the throttle itself.

2. Clicking that you hear after start-up. Have you always heard this clicking or did this start after you hit the curb? If after, then I am wondering if you are just not hearing it click/engage when you are driving with the additional road/engine noise. Once it engages it would open the fuel pump circuit that results in the 3rd problem. Check for codes.

3. Truck dies as you driving. I think you have to figure out #2 first. Could be the relay, the wiring or loose connector. Then again it could be totally unrelated. I doubt it though. Check for codes.

Wish you were closer, I'd tell you come on over. I'd love to be able to climb into this on with a multimeter and the FSM.

That pretty much sums it up. I know nothing about this, but really wanting to learn how to do this type of stuff so your help (and this forum) is invaluable.

1. I can see the throttle itself hanging. Even when manually pressing the throttle under the hood, it hangs.

2. The clicking started after I hit the curb. It wasn't technically a curb, but pulling into a parking lot where it meets the road was higher and I hit it pretty hard with both wheels (traffic was heavy, I was hurrying across two lanes of traffic). I didn't mention this before, but it died when this happened and this is the first time I've had the truck die. I've owned the truck for a little over a month, and up until this happened about a week ago no issues with it dying.

3. I think related to number 2 just because of the timing. See previous post, it's throwing code 51.

 

[helo-mech]

It's not throwing a CEL, but I checked for codes and got 51. Looked it up but it's only listed as switch signal, doesn't really tell me anything.

Yeah your gonna have to run through the trouble shooting for the Throttle Position Senor circuit. Your mechanical linkage issue will throw it off. Your gonna have to fix that before you can really expect the TPS to work correctly. Maybe this is what is making the Open Circuit Relay click and or the engine to die, but you won't really know till you get the linkage fixed.

I'd bet there is still an issue with the relay circuit (relay, wiring, ground, etc) that is causing the truck to die.

Remember to check the cattywompusness on the TPS connector. After you get bust out the FSM and a meter that is.

 

[ARK_SWAMP_RIDER]

Yeah your gonna have to run through the trouble shooting for the Throttle Position Senor circuit and the others listed if you have an A/T.

What others are listed? I'm looking on www.toublecodes.net and it only lists switch signal in the description. It's a manual btw.

41 Throttle Position Sensor signal.
42 Vehicle Speed Sensor signal.
43 Starter signal.
51 Switch signal.
52 Knock Sensor signal.
53 Knock Sensor signal.
54 Inter-cooler ECM signal.

 

[ARK_SWAMP_RIDER]

So error code 51 could be A/C related? I know there are issues with the A/C. The line going into the cab has been cut and is missing. I've also discovered issues with the actual AC switch. Behind the glove box I found a jumper wire between two of the speed control wires. There are 4 speeds, let's say 1 is low and 4 is high. With the jumper wire connected, 1 doesn't work, 2 and 3 are reversed, and 4 works. IIRC with the jumper disconnected, only one of the speeds worked.

 

[ARK_SWAMP_RIDER]

So I've tried using the FSM I have, but it's proven to be quite a challenge. It's in a PDF format, but it isn't searchable. I'm having to scroll through almost 1500 pages to find the appropriate section. Is there an easier way to do this?

 

[helo-mech]

So I've tried using the FSM I have, but it's proven to be quite a challenge. It's in a PDF format, but it isn't searchable. I'm having to scroll through almost 1500 pages to find the appropriate section. Is there an easier way to do this?

Mine is not searchable either but it does have bookmarks on the side. Do you wanna try mine? It is a 85 4Runner FSM but it should be close.