Code 31 and 22 keep coming on

1988 FORD F-150
165,000 MILES • 5.0L • V8 • FWD • AUTOMATIC
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BRABBIT
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Okay, I have a really annoying problem that I just cannot figure out. I have been getting codes 31 and 22. We took it through emissions and it failed horribly. So we got an obd1 ran the codes and replaced the EGR sensor and map sensor we also got a new O2 sensor PCV sensor and a new EGR valve. We replaced the spark plugs got a new fuel pump and filter checked all the lines to make sure there was no vacuum leak and when we were all done the truck ran smooth. We took it through emissions and it passed with flying colors the truck ran like a dream then about three days ago the check engine light came back on and it started running rough again and the same two codes are popping back up. we replaced the whole system and its still reading the codes we even checked the new parts to make sure they weren't defected. Now here is the part that is messing with us we went outside to turn it on this morning and the check engine light was off the truck was running smooth we drove it all day with no problems went to turn it off . a few minutes later we turn it back on and the truck started running rough again the check engine light back on and the same two codes popped back up. I have no idea what else to do. The last thing I can think of is carbon build up but I am not sure. Is there anyone who might know what the problem is your suggestions would be very helpful at this point? Also, sorry for the long message.
May 1, 2017 at 3:43 AM
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HMAC300
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first thing did you pull ECM fuse for thirty seconds to erase the old codes if you did not they will stay. See pictures for diagnosis of code 31 code 22. you need a tester for map sensor but check for a vacuum leak as well as a bad purge valve, it should only open at thirty mph so at idle it should be closed there is one vacuum line going to it and one to tank. it is normally a red valve under hood on canister.
May 1, 2017 at 6:51 AM
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ICEMAN3535
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I have the same problem with my truck. Code 22 keeps putting up. Bought parts an still the same
Jul 30, 2017 at 5:30 PM
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HMAC300
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read the previous reply on what to check
Jul 30, 2017 at 5:43 PM