Flashing CEL with no code
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Flashing CEL with no code
I have a 99 ford f350 with the v10 and 180000 miles, stock engine except for K&N filter. Around June it died and I replaced the tps and it worked for a couple months then the same problem came back. I have since replaced the tps, pigtail coming off the tps, cleaned the throttle body and MAF. Currently at the shop but they can not duplicate the problem. Always the same problem, revs up once on its own, cel starts flashing erratically and then it starts running rough. It will usually die within a minute or two after it revs up. The shop thinks it might be a gem module. Any other ideas?
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GEM shouldn't have anything to do with how the engine runs, nor the CEL light (see my signature for disclaimer)...
Check the voltage at the battery, do the headlights flicker when it's running? Sounds like electrical interference from somewhere, and the alternator having a bad diode (or many) would do drive the PCM nuts.
Check the voltage at the battery, do the headlights flicker when it's running? Sounds like electrical interference from somewhere, and the alternator having a bad diode (or many) would do drive the PCM nuts.
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GEM shouldn't have anything to do with how the engine runs, nor the CEL light (see my signature for disclaimer)...
Check the voltage at the battery, do the headlights flicker when it's running? Sounds like electrical interference from somewhere, and the alternator having a bad diode (or many) would do drive the PCM nuts.
Check the voltage at the battery, do the headlights flicker when it's running? Sounds like electrical interference from somewhere, and the alternator having a bad diode (or many) would do drive the PCM nuts.
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Denny
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if you have been running your truck and it's 12.5 after you shut it off then you have a battery or alternator problem, battery should read 12.6 after setting over night and 14 or above right after it was shut down. After starting the voltage at the battery should be in the 14.4 range.
Denny
Denny
I had the battery tested today and it came up as bad and needed replacement. Alternator was good. Replaced it tonight, hopefully it will solve the problem.
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Denny
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These new trucks have so much electronics on them and they need a good clean power source, a battery is a great DC filter but if it starts going bad the electronics don't like it. We were with a couple that had a Dodge truck and the transmission was acting up and after a complete rebuild it still was doing the same thing. I turned out to be a bad alternator.
Denny
Denny
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no stored codes. I have ran my reader and the shops reader on it and there is nothing stored. I have also ran it right after it happened before I turned the key off and nothing was there.
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I have a 99 ford f350 with the v10 and 180000 miles, stock engine except for K&N filter. Around June it died and I replaced the tps and it worked for a couple months then the same problem came back. I have since replaced the tps, pigtail coming off the tps, cleaned the throttle body and MAF. Currently at the shop but they can not duplicate the problem. Always the same problem, revs up once on its own, cel starts flashing erratically and then it starts running rough. It will usually die within a minute or two after it revs up. The shop thinks it might be a gem module. Any other ideas?
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Latest update. I figured out that something was causing the trucks computer to lose connection whenever the problem happened. I would run a hand held scanner as the truck was stalling or right after with the key still in the on position and the scanner would not be able to communicate the the computer. I pulled the computer out and found it had a SuperChip, on a hunch I pulled the chip out and reinstalled the computer. It has been two weeks since I have removed the chip with no problems or stalling.
Glad you got it figured out!
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