Q: High idle 1500 rpm

asked by on November 12, 2017

Upon start up truck will idle at 1000,after 10 seconds it climbs to 1500 and remains there. Before this problem idled at 700 at all times. Since problem started replaced IAC, TPS, MAP, CTS, was getting codes for those so replaced them thinking problem would solve but still the same. I also replaced throttle body gasket and no change. I have searched for a vacuum leak and have found nothing. Right now I believe the truck is undrinkable, I also unplugged battery to reset computer but didn't do anything either. Any suggestions? Anybody have experience with these TBI motors?

My car has 258000 miles.
My car has a manual transmission.

Engine idle speed is high Inspection $79.99 - $99.99 Get a Quote

I would look again real carefully for air leaks. Some of them can be pretty tricky. There might be a leaky component or even a leaking brake booster. A can of carb cleaner can help with this, but you’d better have a fire extinguisher handy. The next thought is that there is some buildup on the throttle plate that is preventing the throttle from closing completely. This can often be remedied by removing the throttle body and giving it a good cleaning. If you don’t find anything there, I suggest you have it checked out to be sure your money is going to the right place. You can have that done at your convenience by contacting YourMechanic. They can send a technician to your home or office to check out your high idle problem and tell you the solution.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

What causes the mileage area to blink then say no bus?

Hi there. The No Bus message is actually a pretty major issue that is common with late 1990's and early 2000's Dodge vehicles. It's actually telling you that there is a communication error to the ECU, or the Engine Control...

ABS lights on after rear ended accident 2009 Toyota Prius

Hi there - it is unlikely that the accident caused the ABS error in question. There are, however, issues with over-sensitive monitoring of brake system "false positives" by the ABS software documented in Toyota Technical Service Bulletins (342345, 342346, 342347)....

Air conditioning pressure doesn't change when clutch is engaged.

If your expansion valve was stuck in the open position then you may not see much, if any, change in pressures. Before replacing the expansion valve I would recommend you remove the compressor inlet line and turn the compressor by...

What would my next step be? Wheel bearings are driving me crazy!!

This is a common sound when wheel bearings are badly worn and need to be replaced. When they wear out, the bearings begin to grind metal on metal which as you know creates an intense heat. This can be dangerous...

Car keeps overheating

When a car overheats when it is sitting still or moving slowly, this is because the cooling fans are not turning on. If the car is fine while moving, the thermostat is fine, although, anytime a motor overheats, it can...

Car turning over, but it will not start.

You may need to have the key re-flashed to the car's computer. It sounds like every time you leave the car it has a problem re-associating itself with the car. I would recommend taking it back to the Chevy dealer...

Related articles

The Best Used Cars to Buy If You Have Kids
Once Once you have kids, the kind of car you have becomes very important. Suddenly, the amount of space, entertainment features, reliability, safety, and easy to clean interior become the top priorities. Here’s a list of vehicles meant to satisfy...
A Buyer’s Guide to the 2012 Chevrolet Cruze
Until Until just the past few years, the Toyota Corolla and the Honda Civic were the kings of the compact car class, and domestic manufacturers had almost nothing in the way of competition for these models. With the 2012 Chevrolet...
Understanding Chevrolet Oil-Life Monitor (OLM) System and Lights
Car symbols, or dashboard lights, are a car service reminder. The Chevrolet Oil Light Monitor system indicates when and what service your car needs.