2012 ford fiesta with 1.6 l engine thats driving me nuts .....lol

hi mr paul danner i am a a student on scannerdanner premium, let me start by saying thank you for giving me hope and a career to pursue. God bless for your knowledge and my you never lack.....amen i have a 2012 ford fiesta with a 1.6l engine with a cam sensor code. i have checked the cam sensors with an oscilloscope and i have signals on both the inlet and exhaust cam sensors..... knowing that a faulty crank sensor can set a false cam code, i pursued on to check the cranks and thats fine too. when the cam sensors are unplugged, the bais voltage i learnt from your class is there on both sensors..... Could this be a potential PCM problem or faulty software perharps? pls help me our sir and i do hope for a rapid response from you...... thank u very much Sir and keep up your Good work....... God bless you for the work you are doing. this is Michael your online student from Accra Ghana

Hey Michael, do you recall what code you had, exactly? Or, was it more than one code? Are these hard faults, or do they take some time to reset?

Knowing Ford, it's possible that you're looking a cam/crank relationship issue, especially if you have codes for both camshafts. This is a belt system with keyless belt sprockets, which means you can easily end up with timing issues. Aside from a cam/crank waveform, the only way to confirm timing is with the covers off and a special tool set.

yes the code its sets is a p0340 camshaft circuit malfunction code and the code appears right after start up even when the codes are cleared before starting the engine

yes but one funny thing is that when the sensors are unplugged the bais voltage of 4.95v is there

michael4real wrote: yes the code its sets is a p0340 camshaft circuit malfunction code and the code appears right after start up even when the codes are cleared before starting the engine

Gotcha, thank you for clarifying! And both CMP sensors are producing clean 0-5V signals? If there's any doubt, you can always see if the sensors are the same part and swap them. If the code follows, you know where your problem lies. We can be pretty sure the wiring is good, because the sensor is producing a signal, and the bias voltage is present.

I know that the stated 'Possible Causes' for this code are all circuit related, but I've seen several Ford products set this code due to timing issues. What the description SHOULD say is this:

"This DTC sets when the PCM can no longer detect the signal from the camshaft position sensor in the position that the PCM is looking for it to occur."

yes bro i get that but i already swapped them out thinking that will solve the issue but it didn't , so are u saying this could be a timing issue or a pcm or a software problem????

Can you check the syncronistion using a scope against a known good wave form?it may be a corrosion issue at the pcm,not unusual,maybe scope sensors at the pcm,

I've seen issues on a Ford crank sensors where the wiring had been repaired with splice the polarity of 2 wires was reversed.

michael4real wrote: yes bro i get that but i already swapped them out thinking that will solve the issue but it didn't , so are u saying this could be a timing issue or a pcm or a software problem????

Possibly a timing issue? Like Landroverman1958 suggested, a cam/crank waveform would be my next suggestion. A two channel scope would work. Intake cam on one, exhaust cam on the other. From looking at other known good patterns, the two cam signals are mirror images of each other, so any timing issue will be obvious. You can also change up and have the crank on one channel, and either cam on the other.

Tyler -

Wouldn't intake and exhaust cam position sensors only definitely mirror each other at idle? Isn't it true on many newer automobiles that VVT could have the intake and exhaust valves overlap at higher RPMs?

Did I misunderstand your suggestion? If so, sorry about that.

GeekDIYMechanic wrote: Tyler -

Wouldn't intake and exhaust cam position sensors only definitely mirror each other at idle? Isn't it true on many newer automobiles that VVT could have the intake and exhaust valves overlap at higher RPMs?

Did I misunderstand your suggestion? If so, sorry about that.

Yah, you got it. I figured that, since it's setting a hard P0340, the VVT is likely disabled anyway.