1 scan 5 codes
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1 scan 5 codes
after a 150 miles of thinking all was well today after work I started my truck and all heck broke lose. the idle was very rough and the check engine light came onthen started to flash so I went by AZ and got these 2 codes po300,301,304,402,420 I gotta believe that these are connected some how, I was afraid of a blown head gasket but with misfires on both sides of the engine that seems unlikely.any input
Post Fiend
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From: Connecticut
Is this the '97 3.0L?
Sounds like there is some sort of timing problem, either ignition or fuel.
Something to consider is that the 3.0L OHV is prone to camshaft position sensor/synchronizer issues (the CMP controls fuel injection timing).
The 402 code is nomally associated with a bad DPFE sensor.
Sounds like there is some sort of timing problem, either ignition or fuel.
Something to consider is that the 3.0L OHV is prone to camshaft position sensor/synchronizer issues (the CMP controls fuel injection timing).
The 402 code is nomally associated with a bad DPFE sensor.
Former ******
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I agree, a cam position sensor could cause the misfire codes (300, 301, 304). Those codes mean random multiple misfire, misfire cylinder #1, and misfire cylinder #4. They could be a genuine misfire, but the signals from the cam sensor are used to check for misfires. The 402 is probably related to the EGR system I'm pretty sure. The P0420 means catalytic converter efficiency below threshold. Resolve all other issues before tackling this one. If the converter is bad, it is caused by the other problems. You can also sometimes get a false code, because the converter cannot operate efficiently under the current conditions. So if the conditions are corrected, the converter may start working again.
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Originally Posted by Bear River
I agree, a cam position sensor could cause the misfire codes (300, 301, 304). Those codes mean random multiple misfire, misfire cylinder #1, and misfire cylinder #4. They could be a genuine misfire, but the signals from the cam sensor are used to check for misfires. The 402 is probably related to the EGR system I'm pretty sure. The P0420 means catalytic converter efficiency below threshold. Resolve all other issues before tackling this one. If the converter is bad, it is caused by the other problems. You can also sometimes get a false code, because the converter cannot operate efficiently under the current conditions. So if the conditions are corrected, the converter may start working again.
Postmaster
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I would say odds are slim to none that it is the MAF. Spraying around intake would be to check for a vaccuum leak. If you had a vaccuum leak you would more than likely have p0171 and/or p0174 codes. Also a dirty MAF could cause p0171/p0174 codes which you don't have listed.AS far as the codes you have vaccuum leak and MAF wouldn't give you the codes you have. I would check what everyone else has suggested so far.
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I Am Also Wondering Since 1 And 4 Are Located Across From Each Other If Maybe There Is Somrthing To Look At That
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ANOTHER QUESTION, i HAVE HAD THIS PROBLEM IN THE PAST AND CLEARING THE COMPUTER SEEMS TO ELIMANATE THE SYMPTOMS FOR AWHILE. WHAT i AM WONDERING IS SINCE MONEY IS A LITTLE TIGHT AM I HURTING THE ENGINE DOING THIS UNTIL I CAN SEE A MECHANIC BECAUSE THIS SEEMS TO BE BEYOND ME AND I CAN'T KEEP THROWING PARTS AT IT
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Post Fiend
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From: Connecticut
Originally Posted by darsacal101
ANOTHER QUESTION, i HAVE HAD THIS PROBLEM IN THE PAST AND CLEARING THE COMPUTER SEEMS TO ELIMANATE THE SYMPTOMS FOR AWHILE. WHAT i AM WONDERING IS SINCE MONEY IS A LITTLE TIGHT AM I HURTING THE ENGINE DOING THIS UNTIL I CAN SEE A MECHANIC BECAUSE THIS SEEMS TO BE BEYOND ME AND I CAN'T KEEP THROWING PARTS AT IT
Sometimes only the CMP sensor (not the synchro shaft gear) fails and that can also cause havok with the fuel injection timing. Replacing the sensor is fairly easy, much easier than replacing the entire CMP syncronizer assembly.
Check out: https://www.ford-trucks.com/forums/2...placement.html
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I would hope that the synch is not out I just replaced it a year ago, and my oil gauge shows good oil pressure...I noticed that one cause for the p0300 code could be a stuck open EGR valve so I am going to try replacing the valve because it has a good bit of crud in it already I will also check the cam sync sensor
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If it is not the cam sensor, other things to look at is the ignition system, since that can cause a misfire. Just use OEM plugs and wires, and check the resistance of the coil pack. If the resistance is in normal range, then either the coil is not getting the signals to fire (back to the cam sensor), or the circuit is somehow broken. A digital multimeter can be used to test the coils. The misfire and the EGR code could be related, since the DPFE is affected by flow. My advise, track down the source of the misfire, reset the codes, then see what comes back, and then deal with that accordingly.
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that is what I am attempting to do ....when I pulled the sensor off of the synchronizer I found oil inside of the sensor....my common sense tells me that sensors won't work correctly with oil in them but I am wondering if this is actually the case
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well I have checked all spark plugs,coil,fuel pressure and attempted to locate possible vacuum leaks with a can of carb cleaner....I am being told by mechanics her that the cam shaft synchronizer would not cause the misfire codes...does anyone know why....
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From: Connecticut
Originally Posted by darsacal101
I am being told by mechanics her that the cam shaft synchronizer would not cause the misfire codes...does anyone know why....
How much oil did you find in the CMP sensor? There really shouldn't be any oil in there. The sensor "cavity" part of the syncronizer shaft is seperate from the lower portion (w/gear) that mounts down inside the engine.
If it's not a CMP problem, then ignition-wise another thing on the list of suspects could be a bad crank sensor which is probably the single most important component responsible for maintaining proper spark timing.