Question about 1995 Toyota 4Runner

1 Answer

1995 toyota 4runner 4x4 Idling high sometimes than idles real low too

Sometimes I'll start it and it'll want to idle high around 1500rpms, but than it will start and idle low enough to kill motor

Posted by on

Ad

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Toyota Master
  • 20,706 Answers

Rule 1 on all otto cycle gas engines.
idle is the last thing to work right.
on EFI , its under control at all times.
but if the engine runs bad, it goes out of control.
IS THE CHECK ENGINE warn, lamp glowing running, ????
yes, why not get the DTC codes, (flash error codes now)
when it runs bad, is it misfiring, and shaking engine, weak power from engine,, bogging, or only stalling.
low rpm is near stall and is same thing.
1500rpm is perfectly normal for any cold engine.
Hot , its not.
first off check all fuses.
The idle controls are called ISC, "idle speed controller"
its a slave valve and ECU logic and servo controls.
the ECU works overtime , keeping idle right.
if the ISC sticks, it fails.
if the EGR sticks open , the ISC loses control
if the you get intake (induction) air leaks it loses control
same for misfire, gross, flooding. same for gross lean.
so how do we do this? find a cause.\
easy we give that long missed 60,000 mile tune up.
and during that i clean the ISC and EGR main valves.
on any old car like this, wow, its sure to be a mess, if not serviced.

then make sure the EGR main is closed,
engine hot.
i see if my ISC is trying to work.
i then check my fuel mixtures. to see if the engine EFI
reaches and holds closed loop.
oops, it cant be cause the 0xygen sensor died, 100k miles ago.
its dead.
no OTC scan tools for 1995 ( sure hackers have em)
so is very hard to get this information, i use a scope to watch my oxy sensor, if stuck rich i fix that first. if stuck lean , i find the exhaust crank causing it. or other cause... long list of tests.

in a real shop the start at the tail pipe end, OMG this puppy is rich as a pig and work forward, is start at the oxysensor
i get it working by any means.,
then fix idle if not already magically working. as most do (cleaned)

here is a very common example.
1: EGR sticks open at idle. IDLE RPM drops like rock. ( it must)
2: ECU sees illegal RPM and opens the ISC fully, to no avail.
some cars EFI hunts the ISC causing surging.
others ECU just slams the ISC wide open and does a software hope thing. in this case, does nothing,due to gross EGR misfire effects.
the idle controls are a SERVO,. a closed loop servo system.
it regulates idle until , something horrible happens.

it fails when conditions are outside it's range of Authority.







Posted on Feb 12, 2014

Ad

4 Suggested Answers

6ya6ya
  • 2 Answers

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

Hi,
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.
New users get 2 Free calls (no credit card required) and instant help on almost anything you can think of (from cars to computers, appliances, handyman, and even pets).
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad
  • 1861 Answers

SOURCE: fuel injection idling to high

Try this: Remove the rubber pipe that goes to the throttle plate at the end of the intake manifold. Open the throttle flap valve and inspect the interior for excessive carbon buildup (black gunk around the flapper and the outer circular bore)...If it is dirty, get some carb cleaner & spray the daylights out of it until it is clean clean clean. Reattach the tube and start the engine, it will smoke quite a bit until all of the cleaner in the intake is digested by the engine. This should improve the idle. What may be happening is the black gunk may not be letting the throttle valve to close fully, and WILL keep the idle up.

Posted on Sep 19, 2008

localwonder
  • 6784 Answers

SOURCE: 86 toyota 4runner idles low and has half the power

Ok, there are four problem spots that i recommend inspecting the first would be the air filter.

The air filter may be clogged or dirty. this can decrease the power out put and it can also affect the idle as well. the next check point would be inspecting the spark plugs. make sue the plugs are correctly gapped and are not fouled in anyway. if they are fouled or incorrectly gapped, this will cause the symptoms you are experiencing at this time. Another check point will be the wire set(spark plug wires). make sure the wires are in good condition. remove all wires from the plugs and look inside the wire head t inspect the contacts. they should be nice and clean.if the wires are worn, replace them accordingly. the final check point will be checking the PCV valve. this valve is located Under hood, center, upper engine area, top of engine, mounted in valve cover. the testing procedure to be preformed on this specific device is stated below.


PCV VALVE TESTING PROCEDURE---

# Check the ventilation hoses and lines for leaks or clogging. Clean or replace as necessary.

# Locate the PCV valve in the cylinder head cover and remove it by pulling it upward.

# Blow into the crankcase end of the valve. There should be free passage of air through the valve.

# Blow into the intake manifold end of the valve. There should be little or no passage of air through the valve.

# If the PCV valve failed either of the preceding two checks, it will require replacement.


You will find the problem for you erratic or low idle in the areas above.

Please rate and god bless:)

Posted on Apr 27, 2009

alicantecoli
  • 22219 Answers

SOURCE: my toyota corolla 2e (big body) model 1995 is

just adjust the auto choke idle control

Posted on Mar 29, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

My van is idle high i cleaned the throttle boady and it idle down the a few hours later its high idle again why i replaced two sensor and still idle high


Hi Alexandra, Im AL the owner of Big As Auto Repair

There are several things that can cause high idle, but the 2 most common problems are as follows.

(1) You could have a vacuum leak somewhere on the engine. Here is how to check for that issue. Here's what I want you to do: Buy a can of CARB Cleaner and while the engine is running spray around the Intake Manifold, the manifold is the thing the throttle body sit on. Also spray around all the vacuum line as well. If while spraying there is a change in the idle speed then you have found your leak. If there is no change then move on to step 2.

(2) Sometimes when you have a high mileage vehicle parts begin to ware out or can also begin to stick in place. Here something you can check. Idle Air Control Motors can start sticking from corrosion build up and can cause a high idle issue. Here what I want you to do. Start the engine and let it idle, while its idling I want you to tap on the Idle Air Control Motor If it idles down to normal idle speed replace the motor. The motor mounts onto the throttle body and most of them are round. Once you replace it and start the engine you'll notice that its idling real high, :This Is Normal, just let it idle until the engine controller resets the idle speed to normal.

Hope this helps and should you need further help please visit my auto repair website. http://www.bigasautorepair.com/

May 25, 2015 | Cars & Trucks

2 Answers

My pontiac aztek '01 doesn't always want to start. Have to tap gas to get it to start. Sometimes it idles really low...other times it idles high and acts as if I'm giving it gas when I'm not. Any ideas?


The computer controls idle through the idle control valve or motor. Sometimes deposits build up around it or in the air passages it controls. If it is taken off and cleaned, it might help. Use a good quality sensor safe cleaner. Check if the passages are clear.
Or if the throttle position sensor is going bad, it could cause those problems. The sensor can be tested with a multi-meter.
Have you checked for any trouble codes?

Nov 14, 2013 | Cars & Trucks

1 Answer

99 vw passat. recently had to start unplugging my battery due to a relay going out. lost my primary headlights, wipers, turn signals, air flow and now my power stays on, hence why i unplug the battery. yet...


Sounds like a combination of problems. First your battery is dead, and your alternator isn't putting out enough to run car. As for relay, replace it. I had a coil pack go out on me after I had other electrical issues so that's possible too. Go to VWvortex.Com and search the forums

Sep 08, 2013 | Cars & Trucks

1 Answer

Idle problem integra


check the MAP sensor (manifold absolute pressure). The ECM (car computer) uses that to keep idle at minimum 750 RPM. It's normal for it to run high when cold. These small 4 banger motors typically run hot, and they won't run right IF they're NOT running hot, ergo the idle is usually high when it is cold so as to cause it to warm up quicker. If the RPM's drop below 750, suspect the MAP sensor, &/or ECM.

Apr 18, 2013 | 1995 Acura Integra Coupe

1 Answer

High idle


What control idle is RPM sensor[TPS] to check it is OK.

Jan 28, 2013 | 1999 Pontiac Grand Prix

1 Answer

Car idles high


when it is cold out there is a sensor on the throttle body that has the rpms to go high so the engine warms up fast then it suppose to drop back to nornal. the sensor is a idle air control valve. here is my linkhttps://www.facebook.com/TedsRepairs

Nov 12, 2012 | Cars & Trucks

1 Answer

When at a stop light sometimes my firebird, which is a manual tranmission, revs up to 2200 rpms. fuel mileage had gone from 23 miles per gallon to around 9 or 10. help please its killing me!


Hello and welcome to FixYa!

I strongly suggest that you have the IACV (idle air control valve) replaced. If the IACV is worn out it tends to make the rpm high or low. High rpm will surely result to unusual fuel consumption. Once replaced I believe you'll be good.
Hope this helps and thank you for using FixYa! Have a good one!

Jul 10, 2011 | 1991 Pontiac Firebird

2 Answers

Engine will start at very low idle, sometimes killing, then may fast idle, then low idle, back and forth. What may cause this?


check and make sure air filter is ok, and there are no restrictions in hose to throttle body, check iac (idle air control.

Oct 01, 2009 | 1990 Chevrolet Corsica

1 Answer

My car kills when at idle. has low r/min at idle.


Check the Idle Air Ctrl (IAC) motor. It should allow air to bypass the throttle plate when starting and at idle. if it is not working it could cause veh. to stall.

Aug 02, 2009 | 1996 Cadillac DeVille

1 Answer

Intermittant Idle problem


Try this:
Here is the most common cause of surges and stalls and low idle, it is the idle speed control air-bypass valve and throttle valve, they get full of gunk over the miles and cause idle issues (stalls, low idle) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.

Jan 13, 2009 | 1999 Ford F150 Regular Cab

Not finding what you are looking for?
1995 Toyota 4Runner Logo

156 people viewed this question

Ask a Question

Usually answered in minutes!

Top Toyota Experts

yadayada
yadayada

Level 3 Expert

76630 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8516 Answers

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

Answer questions

Manuals & User Guides

Loading...