Welcome Visitor! Please take a few seconds and rolltide6019
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- Joined
- Feb 3, 2018
- Messages
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- Vehicle Year
- 1998
- Make / Model
- Ford
- Transmission
- Manual
Guys, new to this site - thank you all in advance.
On my 98 4.0 OHV I've been working on a P0340 (camshaft circuit fault). So here's the deal...this fault existed before I changed the engine. I put another synchronizer and sensor on it AND I can see the pulses on my oscilloscope going into pin 85 on the ECM; a nice square wave of about 13v. I figured it must be the ECM since all the right signals were there so I purchased a new one. There is no difference with the new ECM. So I have a new CPS, new ECM and the wiring checks out between them and I have a signal that matches whats suppose to be there (far as I know). There are no other codes. I've read in some forums that a bad alternator can cause this but I've disconnected mine but it didn't make any difference. After you clear the code, it appears immediately when you crank the engine up. The engine runs pretty smooth overall. So what can be causing this continual P0340? What else haven't I considered or checked? BTW, this is a 3-wire sensor (not 2 wire)
Thanks for the help!
On my 98 4.0 OHV I've been working on a P0340 (camshaft circuit fault). So here's the deal...this fault existed before I changed the engine. I put another synchronizer and sensor on it AND I can see the pulses on my oscilloscope going into pin 85 on the ECM; a nice square wave of about 13v. I figured it must be the ECM since all the right signals were there so I purchased a new one. There is no difference with the new ECM. So I have a new CPS, new ECM and the wiring checks out between them and I have a signal that matches whats suppose to be there (far as I know). There are no other codes. I've read in some forums that a bad alternator can cause this but I've disconnected mine but it didn't make any difference. After you clear the code, it appears immediately when you crank the engine up. The engine runs pretty smooth overall. So what can be causing this continual P0340? What else haven't I considered or checked? BTW, this is a 3-wire sensor (not 2 wire)
Thanks for the help!
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