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Robert, RVIA Certification
Category: RV
Satisfied Customers: 5
Experience:  15 years exp.,Level 2 Onan Cert,.Dometic cert,. extensive a/c exp
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1990 454-motor home,one day..check engine light,put code reader..cap

Customer Question

1990 454-motor home,one day it stays running the next time it won`t I had check engine light,put code reader on,started then turned off,found out I wasn`t suppose to start the motor with reader hooked up,now it won`t stay running at all,starts good,runs about 1 min. then stops.replaced fule filter changed fule cap
Submitted: 6 years ago.
Category: RV
Expert:  Robert replied 6 years ago.
Helllo my name is XXXXX XXXXX for coming to our site.First ,have you tried reading codes again with the key in the on position but not running.[running engine with code reader attached to rv WONT hurt anything, infact there is a test that does just that].If you got any codes from this let me know.Next I would check for proper fuel pressure from pump.It should be 9-13lbs.If that is correct then i would check the exhaust system.Inspect the catalytic converter for excessive rust or damage.If it looks okay then find the o2 sensor and try to remove it.With it removed try to start the rv,if starts and continues to run the catalytic converter is plugged[causing to much back pressure].Let me know if any of this helps.
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Customer: replied 6 years ago.
no codes,will try pressure test today Dale
Customer: replied 6 years ago.
I tried the preasure test got 10 lbs for about 30 sec. then it started loosing preasure till 0 and motor stalls
Customer: replied 6 years ago.
the motor reves up and runs good untill the fuel runs out,how could the o2 sensor cause this,it has some pressure at tail pipe,but not alot and lots of smoke,when fuel preassure drops it stops even at idle,will not stay running,could this be the fuel pump???pump does not shut off with key on
Customer: replied 6 years ago.
with O2 sensor out it still dies ,with converter off runs longer but still dies.Dale
Customer: replied 6 years ago.
how can i let you know, if you don`t answer,Dale