Q: Check engine light on, codes for air intake temp sensor, catalytic converter, and knock sensor. Car is bucking when going uphill.

asked by on March 08, 2018

Recently purchased the car. Check engine light would come and go for a few days but then stayed on steady. Scan shows for catalytic converter, knock sensor, and air intake temperature sensor. Car drives ok but has been making a chirping noise and bucks when going uphill. So far I have replaced the air intake sensor, new air filter, and used a catalytic converter cleaner.

My car has 211000 miles.
My car has an automatic transmission.

Check Engine Light is on Inspection $94.99 - $114.99 Get a Quote
Loss of power Inspection $94.99 - $114.99 Get a Quote

If the check engine light is presently on your most efficient option would be to request a check engine light diagnostic. The mechanic will resolve all codes and then re-evaluate your situation, that is determine if the engine still misses under load even after all codes have been investigated and resolved. Note that diagnostic trouble codes only provide clues as to the general area of the problem. Consequently, unless you actually tested the air temperature sensor and pinpointed a failure, the sensor might have been perfectly good. For example, you can obtain the identical fault code for the sensor just by disconnecting the wire to a perfectly good sensor. Chirping noises are often serpentine belt related, if not the belt then an issue with the circuit of rotating components. If the check engine light is not on, but you just want the bucking diagnosed and fixed, as well as the noise issue, please instead schedule service via YourMechanic’s engine loss of power diagnostic page. With regard to either diagnostic, if you request service the certified mechanic will get your issues resolved for you, right at your location. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here 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

No pressure to accelerator.
It sounds like there is an issue with your accelerator cable. It is possible that it may be broken or has come detached from the throttle of your engine. I would recommend that you enlist the help of a certified...
Sunroof leak
Leaking sunroofs are never fun to repair. Most of the time the problem on your car is clogged sunroof drains. With the sunroof open use compressed air to blow the drains clear. If they are clear or if this does...
Car shakes and squeaks
Improperly balanced tires usually start to vibrate above 50 miles per hour. This may be fixed simply by having the tires balanced. Have an experienced technician, such as one from YourMechanic, also check the condition of the tires and integrity...
Car shaking during acceleration and shifting between gears
This condition sounds like one BMW has noted on a technical service bulletin (TSB) concerning a software issue in the engine control module. There has been an updated software version developed by BMW but you will need to have this...
2009 Nissan Murano has the P0420 trouble code. It says the normal bank 1 issue, but now it says short to VBAT. What is that and how to fix it?
Hi there. From the description you have provided, for your vehicle's P0420 trouble code (https://www.yourmechanic.com/article/p0420-obd-ii-trouble-code-catalyst-system-efficiency-below-threshold-bank-1-by-jamahl-walker). I suspect the O2 (Oxygen) sensor you replaced has created an additional concern for your vehicle. Either, the O2 sensor is incorrect by application or...
car running very rough, making oil 1990 Nissan/Datsun 300ZX
Hello - I suspect your cold start system (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-cold-start-injector) has gone "full on" or you have leaking injectors. Without question your fuel system is pumping way too much fuel into the intake, leaking past the piston rings, and entering the...
Vibrating or shaking
Hi There, It sounds like you may be having a problem with the vehicle vibrating or shaking. Shaking or vibration (https://www.yourmechanic.com/services/engine-is-shaking-pulsating-or-vibrating-inspection) may be caused by many different things such as faulty spark plugs, poor fuel pressure or misfires. Other things...
about 5-6 oz of water was put in power steering resorvoir how bad is that?
The water in the short term will not hurt anything but should have the system flushed out as soon as possible to prevent later seal and pump or rack and pinion failure.

Related articles

The Best Used Cars to Buy for Occasional Drivers
Not Not everyone relies on their car on a daily basis. Maybe you aren’t the type that deals with a daily commute, and running from here to there constantly. If that’s the case, you may be looking for a car...
The Best Used Cars to Buy for Long Commutes
Most Most of us are faced with the prospect of commuting back and forth to work on a daily basis, but some have a much longer drive than others. When it comes time to buy a car, you need to...
The Best Used Cars to Buy If You're a Rock Climber
If If you’re a rock climber, you want a vehicle that gets you where you need to go, even if the terrain gets rough. You may be living out of your vehicle at times, so you also want a rig...