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P0340 Engine Code Explained: Causes, Symptoms & How To Fix It

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What Does Code P0340 Mean?

  • P0340 definition: Camshaft Position Sensor Circuit Malfunction
  • Issue Severity: SEVERE – Stop driving immediately
  • Repair Urgency: Fix this code immediately (same-day if possible) to avoid internal engine damage.
  • Diagnosis: The vehicle may be difficult to start and the driver may also experience a lack of power when driving. It is possible for more damage to occur inside the engine of the vehicle if disregarded for an extended time period. It is extremely important to repair code P0340 as soon as possible.

The camshaft position sensor located in the internal combustion engine monitors the position and rotational speed of the camshaft. It works hand in hand with the reluctor ring that creates a square wave voltage signal that the ECM interprets as the crankshaft position. The ECM uses this information to control ignition spark and fuel injector timing. When the trouble code P0340 is set, the ignition spark and fuel injector timing fail due to the engine not knowing when to fire these components.

P0340 Causes

There are many potential causes of code P0340. It is difficult to determine which of these is the source of the problem without specialized knowledge.

  • A defective camshaft position sensor.
  • Damaged or dirty reluctor ring on the camshaft
  • Defective, corroded, shorted camshaft position sensor circuit wiring
  • Defective, corroded, shorted camshaft position sensor circuit connector
  • A faulty crankshaft position sensor
  • Stretched or misaligned timing components
  • ECM software update needed
  • Faulty ECM

We recommend reading our guide on how much it can cost to replace a defective camshaft position sensor if you’re thinking about hiring a professional.

P0340 Symptoms

  • Check Engine Light
  • The vehicle will not start – may be difficult to start
  • Rough idle/stall
  • Vehicle engine misfire
  • Loss of power when driving

In many cases, there may be no noticeable issues with your vehicle.

How Do I Fix Code P0340?

With a camshaft position sensor fault, the first step is to get it diagnosed to figure out what is causing the problem. 

If your vehicle has this fault and you’re not comfortable diagnosing this issue at home, we recommend finding a RepairPal certified shop nearby to pinpoint the problem and give an accurate estimate for repairs. 

These shops can not only help you figure out what’s going wrong before you waste time and money on the wrong parts, but they also offer a minimum 12-month, 12,000-mile warranty and stand behind all their estimates with guaranteed fair pricing.

> Find a RepairPal Certified Shop Near You

How Much Does It Cost to Fix Code P0340?

P0340 can be caused by anything from damaged wiring to a bad sensor to a faulty ECM. It’s impossible to give an accurate estimate without properly diagnosing the issue first. 

If you take your car to a shop for diagnosis, most shops will start with an hour of “diag time” (the time spent in labor diagnosing your specific issue). Depending on the shop’s labor rate, this typically costs somewhere between $75-$150. Many, if not most, shops will apply this diagnosis fee to any required repairs if you have them perform the repairs for you. From there, a shop will be able to give you an accurate estimate for repairs to fix your P0340 code.

Possible Repair Costs for P0340

For error code P0340, one or more of the below repairs may be needed to solve the underlying issue. For each possible repair, the estimated cost of repair includes the cost of the relevant parts and the cost of labor required to make the repair.

  • Camshaft position sensor $120-$300
  • Crankshaft position sensor $190-$250
  • ECM $1000-$1200
  • Timing chain or belt replacement $200-$1000

DIY Steps to Diagnose Code P0340

Engine code P0340 could be caused by a number of things, including a bad sensor, damaged wiring, or a faulty ECM. If you’d like to try to fix code P0340 at home without throwing money at parts, you’ll want to follow the steps below for proper diagnosis. Keep in mind this is an intermediate-level diagnosis and repair and not recommended for beginners. Diagnosis requires more specialized equipment beyond what the FIXD Sensor can provide and it can be a time and labor-intensive process for inexperienced DIYers.

DIY difficulty level: Intermediate

This repair requires mechanical knowledge and is not recommended for beginners.

Tools/parts needed (our top picks from Amazon):

STEP 1: INSPECT THE CAMSHAFT POSITION SENSOR WIRING.

Visually inspect the camshaft position sensor wiring in search of corroded, broken, or frayed wiring.

STEP 2: INSPECT THE CAMSHAFT POSITION SENSOR CONNECTOR.

Visually inspect the camshaft position sensor connector in search of corroded or broken connectors.

STEP 3: USE FIXD TO ENSURE NO OTHER ENGINE CODES ARE PRESENT.

Use FIXD to scan your vehicle to verify P0340 is the only code present. Make any other repairs (if other codes are present) to make sure that other codes are not sources of the trouble code P0340. Click here to see what else the FIXD app has to offer.

STEP 4: CHECK THE CAMSHAFT POSITION SENSOR.

Check your camshaft position sensor’s voltage, ground, and signal readings with a multimeter. Check out this video for a visual reference on how to check it using your multimeter.

STEP 5: CHECK THE RELUCTOR RING.

If you find that the camshaft position sensor fails to produce a voltage or a signal, remove it and check the reluctor ring for damage, debris, or misalignment. If the reluctor ring appears in good condition, replace the camshaft position sensor.

STEP 6: CHECK THE CRANKSHAFT POSITION SENSOR.

If the concern persists, perform the same test as you did on the camshaft position sensor to the crankshaft position sensor and its circuits. If it fails the tests, replace it.

STEP 7: CHECK CONTINUITY.

If the concern still persists, perform a continuity test on the camshaft and crankshaft position sensor circuits between the respective sensors and the ECM. Repair any faults you discover.

If these steps do not resolve your Check Engine Light, you may need to visit a mechanic because there may be internal issues with the ECM, stretched or damaged timing components, or the possibility of an ECM software update that may resolve the concern.

Common P0340 Diagnosis Mistakes

Replacing the camshaft position sensor without checking the wiring, connector, or reluctor ring beforehand. There may also be the possibility of neglecting a misfire or timing error.

Still Need Help Fixing Code P0340?

If you’ve followed the steps above and are still experiencing check engine code P0340, please contact the FIXD Mechanic Hotline if you’re a FIXD Premium subscriber or find a RepairPal certified shop near you to get the right repairs at a fair price.

    • Get Your Code Fixed Fast

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Popular Engine Codes P0420 P0172 P00171 P0128 P0300 P0456 P0430 P0442 P0455 P0113

Fixed It But The Check Engine Light Is Still On?

Check engine light sometimes need to be reset manually, check out our article:

How to Reset Your Check Engine Light | 4 Ways To Clear It (With or Without a Scanner)

51 Responses

  1. 06 pathfinder SE, was driving in an ice storm. VDC/OFF- SLIP light has turned on and both won’t go off. Then check engine light. Cam pos. Code pops up. Bank 2 and some other which wasn’t important. Changed both calm and crank sensors. Slip and vdc still on. And now it says as a future problem cam position sensor. No hard starts, no dying out of nowhere. Anyone know what could be there problem or have experience with the same issue?

  2. I have a 2011 Hyundai Elantra, keep getting the P0340 code, I replaced the camshaft sensor twice, the car still having hard time starting when engine is cold. It cranks but need to press the gas for it to start. I don’t know what else it could be. Took it to 2 mechanics and they don’t want even touch it because they think it could be something that will take a long time to diagnose.

  3. 1999 ford explorer the Amp meter shows discharge unless high revving the engine….the fixd app shows a p0340 code cam shaft position sensor. nothing about the amp meter or alternator. no other codes. Engine quits after a few minutes at idle, try to restart, battery dead. Before attempting, vehicle was sitting for about 3 months. trickle charged the battery, which was new 6 months ago.

  4. Wife broke her car; crank no start problem. Downloaded the app, plugged in the FIXD, read the codes, replaced the cam position sensor, all good. Next will have to check out why the check engine light came on my truck.

  5. The engine for my Mitsubishi Galant 2003 won’t start. Code is P0340 camshaft, already replaced the camshaft also put a new starter but still won’t start? Any ideas?

  6. I have a 2001 Mitsubishi Galant ES and it’s saying it’s the crankshaft position sensor I changed it out and still giving me the same code and now my car won’t stay on at all

  7. My 2018 Mazda CX-5 is kicking out this code as well as P250F (low engine oil)*. Dealership is telling me the engine needs to be replaced for $7,000 and they’re not going to cover it. Are they full of it? (*had an oil change two weeks ago at JiffyLube and dealership saying they don’t see leak or blowby)

    1. I replace the camshaft position sensor and everything was fine. Engine light was out and it ran perfectly. I drove about 20 miles to run an errand and on my return trip the engine started missing and cutting out again. It was much worse than before. What could be the problem now?

  8. I have a 2010 Nissan Pathfinder that has been turning over sluggishly for a while now. It cut out today and the codes were PO340/PO345
    now I am wondering if I should just purchase a camshaft position sensor from Auto Parts store and see if I can take care of it myself

  9. I had a code to change cam/crank shaft position sensor, whenever I changed it, it ran fine for about 3 days. I ran it a lot. I am driving and the engine light pops back on — same code. I changed the crankshaft position senor this time, on the bottom — no help. I checked the wiring harnesses for continuity — all good there. Possible I bought a faulty sensor? Help please.

    1. Garret, same thing happened to me…. I went to Oreilly’s and they pulled the code for the cam shaft position sensor (INtake). I replaced it. The engine light was not on when I started the engine after repair. Drove it one day and same code is popping with the engine light back on….Engine seems to be running fine now tho. Cost me $60 so far….will be at least $300 for dealer. Did you find your solution?

  10. I have a 2012 mn triton which stalled going round corner and wont restar code error po340 is it the cam or crank sensor can u tell me the location on this vehicle thanks

    1. I have a 05 Nissan Altima 2.5 that blew a head gasket fixed that now the car tried to start but only if I hold down the accelerator pedal to the floor but still does not start .. I’ve redone the timing twice just to make double sure that it wasn’t 180° out . I’ve replaced the can sensor twice but still no luck in getting it to start .. What is the sensor that is on the front of the timing cover . Perhaps another cam sensor or is something else …please help ….

      Thanks
      Brian in Texas

  11. My Toyota camry stopped working last week pulling up to a stop sign. Wouldnt crank back up. Pushed it to nearby parking lot. Got a code for the valve switch in the evac system. Went and bought the part it said we needed, put it in, still wouldn’t crank and was now showing a code for this cam shaft position sensor bank one circuit A. Got the part again, just finished putting that on. Still won’t crank!!! What else could it be?? Still giving us the code for the camshaft sensor.

  12. 08 Saturn, i4, 115,000 miles. Car is running great. Have spent thousands on the damn error lights. Don’t they ever burn out? Mechanics in TX just disconnected a bunch of wires to shut them off (lost about 2 mpg but passed inspection)
    Mechanics in Maine reattached all the wires and its been a snipe hunt ever since. Parts replaced and replaced again, Oil changes every 5000, added Misery oil, added Rislone, added motor flush. Mechanics have checked wiring, nothing works.
    Engine just keeps on running, 22 mpg, no leaks, burns no oil, starts easy, runs quiet, I think it’s time for an exorcism.

  13. I have a 56 plate zafira 1.6 petrol.
    It has a misfire changed the coil pack and plugs still to no avail idles rough but has brought about 20 codes up help help jelp

  14. i have a Saab 9-3 , arc convertible 2005 code reads po340, i changed crankshaft posiyion sensor and spark plugs, now a still have mild miss when idleing

  15. 2010 Chevy Traverse, turning off highway into drive Car just died. Pushed it to the house noticed battery was old replaced the following day. Ran FIXD no errors came up and car doesn’t turn over. I’ve re-search the issue and timing belt may be the issue, b4 I go that far what are some other signs?

  16. I have a 2012 gmc terrian that is throwing po341 and po340 it stalls when stopped at sings and lights seems like its not got enough fuel dies but does start back up

    1. I have the exact same issue with my 2012 Hyundai Elantra I was told that because it stalls when brake pedal is depressed most likely it due to a vacuum leak at the brake booster and the P0340 code is probably the timing chain. Two separate issues yet only one intermittent code (check engine light not continuously on) P0340.

  17. My 1999 Dodge Intrepid 3.2 engine stalled. I restarted it but the engine light was on. I plugged in my FIXD and got the error code meaning that the camshaft position sensor was the cause of the trouble. I went to O’Rielly’s and picked up a new one. After replacing the sensor, I was able to clear the engine light and have not had any further problems. FIXD was accurate in the diagnosis and saved me a lot of money.

  18. I have a 2011 terrain 2.4 or whatever it is it’s throwing p0340 and p0341 I changed both sensors and it still stalls out and throws the codes I can have my wife and grandkids riding around in a car that stalls on the road any help would be appreciated

  19. I have codes po340 and code p0341 I changed the camshaft position sensor the one on top of motor and the one on bottom it’s still throwing those two codes wires are OK please help what the hell is it

    1. I would look at the timing belt and or tensioner for failure. Also if the water pump is timing belt driven and it fails, it’s possible that the timing belt can skip a sprocket creating an out-of-phase state; hope that helps

      1. KIA sorento 2008 model faultscode…p0340 camshaft sensor…the vechicle is not Firring well especially when you want to climb hill or move fast

      2. It helped me. First Water pump went. Easy fix, Then the chain reaction of everything going. Crank sensor cam sensor fuel pump bcuz of passlock. Finally ECM and timing chain. I never once thougt it all started with the seized water pump.

  20. I got the error code and my wife went on line for info. It was crankshaft position sensor.
    Got a replacement at O’Rielly’s and I was able to replace it. We are glad to have had FIXD TO HELP US.

    1. I recently replaced crank sensor and ecm module no codes jeep was running good one day after driving I tried to restart it and it would not turn over after about 5 minutes it started now I have a code p0340 pointing at cam shaft sensor should I replace it

  21. Is this electronic sensor located on the exterior of the engine and something I can replace, I do have a multi-meter…. how much does the sensor cost ?

      1. While driving I while driving the oil light came on. I stopped and put oil in the car. I continued to travel. The oil light came on again the car lost power and the engine stopped running. It will turn over but won’t crank. It gets a po340 code

        1. I just bought my car from a buy here, pay here place. It’s good to know what is wrong with the vehicle. FIXD gave me a diagnosis. Now I can sound like I know about cars when speaking to mechanics and they won’t think they can rip me off so easy.

        2. I would do if i was you either get rid of the car asap cuz its gonna nickle and dime ya to death or come up with 2500 dollars aand just grab a create engine off line and swap it out that way you know you got another 100 125000 miles to go and most places have flex pay now where tou put a few bucks down and pay it off as you go

      2. while driving the oil light came on. I stopped and put oil in the car. I continued to travel. The oil light came on again the car lost power and the engine stopped running. It will turn over but won’t crank. It gets a po340 code

        1. I’m going to say timing! Broken chain/belt or jumped time either way a pain in the backside! If it is and you have the money replace everything important in the area or you will find yourself dealing with the same issues before you know it!

      3. I have a 97 Rav4 with a distributor and it doesn’t have a cam sensor. It puts out this code. I checked the box crank sensor for fun and it’s good. Now what? Any suggestions? Oh, the motor was just rebuilt… But the code was there before that.

        1. The same ford pickup truck f150 run bad same time i ban have it for over a year put alot. Of work in i do not no y the puge. Dont have fire went the switch is on o test both wings

    1. I had surgery in Oct last year and the car sat for over 5 months until I started it yesterday a week ago . the service engine light came on. What should I actually do to check the correct fault

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Justin Hughes

Recovering autocross and track day enthusiast. Once turned a VW Jetta into a pickup truck. Lives in a van down by the river. Dream car: 2001 Subaru WRC rally car.

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About the Author

Justin Hughes

Justin Hughes

Recovering autocross and track day enthusiast. Once turned a VW Jetta into a pickup truck. Lives in a van down by the river. Dream car: 2001 Subaru WRC rally car.

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