Question about 1991 Toyota Pickup

2 Answers

Idle surges after warm up and when brake pedal is pressed

1991 Toyota pickup 4cyl, 5spd, after complete warm up it idles a little high. Then when you step on the brake pedal the idle goes down and the engine surges up and down. I temporarily fixed the symptom by adding a return spring to the throttle.

Posted by on

  • 5 more comments 
  • superfunk13 Feb 16, 2009

    I Thought it was the brake booster, but i disconnected the vacuum line and plugged it. I started the truck and with a warmed up engine and tried the brake peddle again. It didn't fix the problem, and I'm not sure what else would cause the surging when the brake peddle is depressed. Anybody have other ideas?

  • Anonymous Feb 21, 2009

    i have a 1990 pickup that used to surge when the brake pedal was depressed then it when away for about a month it just came back about a week ago now it does it just sitting at an ide speed with or without the peddal depressed ive checked everything new booster new check valve traced all vaccum lines and still have no clue

  • Anonymous Feb 25, 2009

    I had the same problem, It will be an electrical issue with the brake light switch. Check the light bulbs and the wiring under the bed. Or possible the brake light switch shorting out. I had this problem for months before I figured it out.

  • Phantom302 Apr 06, 2009

    i have a 1989 Toy 4cly pickup that surges when the brake pedal was depressed then it when away for about a month it came back about 9 week ago now it does it just sitting at an ide speed when it's cold 45 outside with or without the peddal depressed I've checked everything new booster new check valve traced all vaccum lines and still have no clue

  • joe dogg
    joe dogg Mar 10, 2014

    i had the same problem and thought it was a vacuum leak. i disconnected everything the same as you did and no change a friend changed the idle control vavle and that took care of the problem. try that

  • Anonymous Mar 26, 2014

    engine starts easily, has high idle.then surges between high and low idle. diagnosis code 12 shows in diagnosis, but runs normally at higher engine speeds

  • Anonymous Mar 28, 2014

    Engine surges at idle why?



2 Answers

  • Level 1:

    An expert who has achieved level 1.


    An expert whose answer got voted for 2 times.

  • Contributor
  • 1 Answer

1990 22re same problem surge when pedal was depressed thought it was booster or check valve still didnt fix it i even put a brand new booster on it just to make sure still no fix it finnally went away on its own for about a month now it does it just sitting at an idle with out the brake pedal depressed traced all vaccum lines no problem there and still have no clue

Posted on Feb 21, 2009

  • Richard Voswinkel
    Richard Voswinkel Feb 20, 2014

    The problem went away when I put the truck into 4-wheel drive. A couple years ago a mechanic replaced the clutch, but didn't reconnect the light which comes on when in 4-wheel drive. Now the surging doesn't go away when I shift it into 4w drive. I'm wondering if there's a short between the 4w drive and an idle circuit. I'm going to try disconnecting the brake light connection at the pedal and see whether that makes a difference.

  • joe dogg
    joe dogg Mar 10, 2014

    idle control vavle most likely the problem


  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that got 5 achievements.


    An expert that has over 500 points.


    An expert who has answered 200 questions.

  • Expert
  • 318 Answers

You have a leak in one of your vacuum lines or circuits.

Posted on Jan 19, 2009


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

A 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
The service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Good luck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Ignition timing

1991 Nissan/Datsun Truck D21 Truck 2WD 3.0L FI 6cyl

The Ignition Timing
15 Degrees Before top dead center*Warm idle speed 750 RPM*Transmission in neutral (Parking brake engaged)*All accessories off.

1991 Nissan/Datsun Truck D21 Truck 2WD 2.4L FI 4cyl

The Ignition Timing
10 Degrees Before top dead center*Warm idle speed 800 RPM*Transmission in neutral (Parking brake engaged)*All accessories off.

Mar 24, 2014 | 1991 Nissan Pickup

1 Answer

1991 Toyota Camry 4cyl idles at 1300 RPM... There is no idle adjustment screw. bad sensor of some sort? Can't pass my smog because the idle is too high. Runs okay otherwise.

look for a vacuum leak into the intake manifold (possible brake booster vac leak), check the idle air control valve for proper operation, check for EGR valve with bad diaphragm or stuck open.

Feb 19, 2011 | 1991 Toyota Camry

1 Answer

My 1989 22re idle surges when warmed up and brake pedal applied. let off the brake it stops surging

Check the vacuum hose from the engine to the power brake vacuum reservoir, it make be loose or cracked and will cause an erratic idle because of the vacuum leak. Please rate this answer, thanks.

Feb 03, 2011 | 1989 Toyota Pickup SR5

2 Answers

1991 toyota

I suspect what you have is a vacuum leak.

1. Try hunting down the leak with carb spray. Don't get too crazy with it, when you get to your leak it will change the way it runs. Also do not deliberatly spray this on spark plug wires as one stray spark and you will need a fire extinguisher. This method is safe, just use your head.

2. If you detect a leak at the brake booster, unplug the vacuum source line for it and plug it. Then trying running the truck again. If it runs normal the leak is in your booster and must be replaced.

Feb 03, 2010 | 1991 Toyota Pickup

1 Answer

Will only start with pedal pressed then idle fine

Try a new throttle position sensor or clean the plug going to it.

Dec 03, 2009 | 1991 Toyota Pickup

1 Answer

Surge in idle when brakes applied or after driving..

block off vacuum hose to brake booster and see if idle returns to normal if it does you need new brake booster has hole in diaphram internally some times slight hissing noise is evident in cab when pressing brake pedal to section where engine surges or idles high. also check for fuel leaks from hoses if you can smell fuel in engine bay while running and engine warm some leaks only leak while running and hot

Jun 14, 2009 | 1992 Nissan 300ZX

1 Answer

High idle@14000 and rpm surge between shifting to 25000

you could have a vacuum leak that is mimicking a throttle that is open further than it really is. Also could be timing that is too far advanced.

Feb 28, 2009 | 1991 Toyota Pickup

Not finding what you are looking for?
1991 Toyota Pickup Logo

2,795 people viewed this question

Ask a Question

Usually answered in minutes!

Top Toyota Experts


Level 3 Expert

77939 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22306 Answers

Jeffrey Turcotte
Jeffrey Turcotte

Level 3 Expert

8832 Answers

Are you a Toyota Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides