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SM 2023
Full Member
Jun 26, 2020
Hello CAFCNA!!!! I'm back again with another code to chase down. P1400-00 This one popped up a couple days of no issues, no CEL. Chasing other codes several days prior, I replaced the Throttle Position Sensor, Mass Air Flow Sensor, and Air Filter. The throttle body seemed to be in pretty good shape. No built-up dirt or anything. It opened and closed easily with no issues or restrictions. The CEL....P1400-00 just popped up after about a good 2 days of no CEL. Also, there's no noticeable performance issues or symptoms. From what I've learned so far, there's a couple thing(s) I know to check but don't know how to actually do it. That's check for exhaust leaks and vacuum leaks. What are the necessary tools, techniques and procedures? What else could be causing P1400-00 to pop up? Thanks to everyone!!!
Could be a gas pedal on its way out
Scan tool with data or freeze frame would help with that
I believe my scan tool has those features...Mucar CDE900 Pro. I will have to figure out how to actually use those features. Any tips or lessons you can provide is greatly appreciated. FYI....I cleared the P1400-00 this past Sunday afternoon. It is now Tuesday morning and the CEL has not come back on...yet. It's my only vehicle so I drive it everywhere. I guess no CEL is a good thing but I'm expecting it to pop back up sometime soon.
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SHOOT!! My apologies to all that are trying to help. There's something I forgot to mention. There's another section on my scan tool labeled SMOG. There were some green and gray boxes and a couple red boxes...EVAP & O2S. My understanding is that means something is undetected or incomplete. I'm not sure what EVAP is and I believe O2S is oxygen sensor. Sorry I didn't provide this information before. I attached a pic of the SMOG reading.


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That o2 could cause your issue for sure.

Evap is the system that vaccumes down the gas tank while it's running and consists of a pressure sensor, purge valve, evap canister and a charcoal canister