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1990 sierra flooding


soulcrusher
08-22-2008, 12:37 PM
it has a rough idle and seems to be flooding. i have replace plugs,wires,cap,button,fuel filter,o2senor,egr and solenoid.it keeps shutting off and has no power and it is rumbleing in the muffler.a friend said it could be fuel pressure regulater in the throttle body. it is a 1990 sierra 305

maxwedge
08-22-2008, 02:29 PM
Look at the injectors in the throttle body make sure both a are spraying, compare one to another see if one is pouring in more fuel than the other, also scan it and look at the coolant temp sensor they are famous for going bad.

soulcrusher
08-22-2008, 08:52 PM
thanks for the help i will try that.we did scan it and the only thing that can up was the o2 sensor.i did not even think about the temp. sensor. Is the fuel regulator adjustable or just the aftermarket ones and do you know about what kind of psi it should hold

maxwedge
08-23-2008, 06:48 PM
Not adjustable, 10-15 psi. regulator is in the the TB.

soulcrusher
08-24-2008, 08:55 AM
i belive itis the map senor when i take the line off of it it tries to idle out.is that common that they go out.it only cost like 50 bucks

maxwedge
08-24-2008, 09:03 AM
You are richening the mixture when the line is off it actually should stall when you do this if everything was working right, points to a fuel delivery/pressure issue. You still have not done the basic required checks here.

soulcrusher
08-26-2008, 03:38 PM
o i did not know that it was to shut off. well i did change the coolant temp. sensor and that did not change the flooding.so do you think it is the fuel pressure regulator? or maybe something different all together

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