Q: Code C342D

asked by on February 11, 2017

My 07 suburban is throwing a code and I can't find any information on it. It's code C342D. Was wondering if you guys had any idea what it is or what may cause it. Truck runs fine for the most part other than when it's at an idle the rpm is showing it's reving up and down. Had this problem before and replaced the tps and it went away. Wondering about that too.

My car has 240000 miles.
My car has an automatic transmission.

Throttle Position Sensor Replacement $144.21 - $717.44 Get a Quote
Idle Control Valve Replacement $162.54 - $1028.01 Get a Quote

Hi there. Either the throttle position sensor (TPS) or the idle air control valve (IAC) is not working. Check the wiring to the TPS sensor and the IAC valve and see if they are plugged in and if there is any broken or frayed wires.

If the wiring looks good and there is no breaks, then start with the TPS sensor. Unplug the sensor and see what the engine does. If the engine starts to run normal, then the sensor is not working.

If there is no change, then I recommend replacing the IAC valve. If you need further assistance with your idle seeking when the engine is running, then seek out a professional, such as one from Your Mechanic, to help you.

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

SRS light illuminated
When a vehicle displays the SRS light, it signals that there is a problem with its’ Supplemental Restraint System, also known as your car’s airbags. When this light is on, your Honda’s airbags are disabled so the system does not...
No fuel pressure
Lack of fuel pressure can be caused by a failing fuel pump or a clogged fuel filter. Depending on the fuel pressure specification, the fuel pump can be condemned. A proper diagnostic inspection should be performed in order to prove...
My car won't let me drive passed 2500 rpm. And I have no idea why it is doing that when I recently bought it.
The reason it will not go over 2500 rpm is because the computer is in limp mode. This mode is for when the computer has a failure in it. Limp mode will trigger if there is an issue with one...
Air conditioner compressor replacement 1990 Ford F150
No, the AC compressors on the two engines are manufactured differently so the compressor from one will not fit the other. If you need help getting the correct part, get in touch with the team at YourMechanic. They will be...
Brake locking - 1990 BMW 750iL
Your vehicle uses a high-pressure hydraulic brake booster. It's likely that the pressure regulator sensors that provide the braking assistance are not functioning correctly, providing too much "braking assistance". A professional mechanic, like YourMechanic, can assist with diagnosis of your...
P0300, P0303, P1313, and P1314 codes are read on the scanner.
Hi there. The codes p0300 (https://www.yourmechanic.com/article/p0300-obd-ii-trouble-code-random-multiple-cylinder-misfire-detected-by-jamahl-walker) and p0303 (https://www.yourmechanic.com/article/p0303-obd-ii-trouble-code-cylinder-3-misfire-detected-by-spencer-clayton_2) are for the engine having a misfire. P0300 is for a random misfire where p0303 says that cylinder 3 had a misfire all the time. The code p1314 (http://obdii.pro/en/code/P1313) means that...
Ok my car will not start it had the same issue a week ago I changed the cam and crank sensors. It cranks but wont start ...HELP!
Prior to performing diagnostics be sure you have a fully charged battery that passes a load test (https://www.yourmechanic.com/services/battery-is-dead-inspection). Then, confirm that the engine immobilizer system (security system) is not activated thus preventing the car from starting. To temporarily override the...
Car says "run mode change system check"
Hi there. This problem seems to be unique to Subaru's and tends to be caused due to a failure within the ECM. The only way to pinpoint the source of this code and determine a course of action is to...
My car will start up and run fine until reaches normal temperature and be hearing clicking from kick pannel and car shuts off
The relay that is clicking is the main computer PCM/Fuel pump relay. The relay may be bad or may be getting overheated from a fuel pump drawing too many amps. I suggest you replace the relay first and then see...

Related articles

The Best Used Cars to Buy if You're Hauling a Horse Trailer
Horse Horse owners need a vehicle with towing capacity. Depending on the size of your trailer and the weight of your horse or horses, you probably won’t be able to get away with less than a 3,000-pound towing capacity, and...
Symptoms of a Bad or Failing Battery Temperature Sensor
Common signs include engine surging, low battery voltage, and an illuminated Battery Light.
How to Replace a Fuel Gauge Sender
The fuel gauge has a sender that goes bad when it says that the fuel level is different lower or higher than it actually is.