My 1999 camry drive belt broke. I replaced it but the car now runs rough and the check engine light stays on. I found parts of the belt had gotten through the timing belt cover opening and behind the belt guide next to and perhaps onto the crankshaft timing pulley. I was able to remove debris with needle nose pliers.

The code is P0340. Is it possible that the timing belt has slipped a cog throwing the timing off just enough to cause the rough engine and the check engine light?

Thanks for any help

 

P0340 is camshaft position sensor circuit malfunction.

The engine computer is not receiving a signal from the sensor.

Check wiring to sensor, sensor, sensor installation and the tooth on the cam sensor used for the sensor.

Sensor resistance
Cold 835 to 1400 ohm
Hot 1060 to 1645

 

Thanks toyomho.

I'll check as you have advised.

 

toyomho

The camshaft positioning sensor wiring looks undamaged, the sensor cold resistance was 1.194K ohms or 119.4 ohms. Within the sensor specs. Can the sensor be considered good?

Whats next? How do I check the tooth on/of/for the sensor?

Thanks ever so much for the help.

 

Is this a 4 cylinder engine?

Are you sure of the resistance reading? 119 ohms is too low.

Check sensor and wiring resistance at the engine computer. The wire colors are blue and black/white. Both wires are shielded.

To check the tooth the timing cover needs to be removed for inspection.

 

Sorry 1.194 kiloohms = 1194 ohms within the sensor specs. Yes, this is a 4 cylinder engine.

It seems strange to me that a drive belt malfunction could affect this sensor. Plus the resistance reading seems to suggest that the sensor should be functioning. But I'm new to this problem.

I guess I'll try to check the tooth but not sure of what to look for.

Thanks again for the responses.

 

What belt was this? Alternator, power steering, timing?

Check if the wiring was damaged. Perhaps a connector was damaged.

If the check light and engine problem occurred right after the belt broke, the two are linked.

Remove upper timing belt cover and examine things plus check cam/crank pulley timing.

 

OK, I removed the timing belt covers. I found one tooth (it looks as if it is made of plastic) for the sensor on the cam gear that looked undamaged. It appears that all the teeth for the crankshaft sensor are there.

I took off both (cam & crankshaft) sensors and found a thin coating of blackish somewhat oily residue. Could that have caused the cam positioning sensor issue?

I found no noticeable timing belt damage but it does seem to have more play than I expected between the cam and water pump. It seems about a 1/2 inch give.

I have yet to check the timing. I'm not sure how to get the motor to rotate. What is the best way to rotate the engine to line up the timing marks?

Again Thanks for all the help.

 

Not sure if the oil coating would make a difference unless an optical sensor design.

If the timing belt is still on. Use the crank pulley bolt to rotate engine CW (only) to align marks. If the bolt is out, reinstall to rotate engine.

Marks should be spot on for proper alignment!

Take spark plugs out to make rotating the crank easier.

To get the proper belt tension. Loosen tensioner. Rotate engine crank CW to align marks, then tighten tensioner bolt.

 

The timing belt shows no sign of wear. I rotated the engine and was able to verify that the timing was correct. I tightened the belt tension. The cam sensor tooth was still on the cam gear.

I put everything back together. I started the car and it is still running rough and still has the check engine light on.

Any ideas of what to check or do next?

Thanks for the help