98 Blazer Fuel Pressure

The motor is a 4.3 with CSEFI system. Last summer the engine developed a lope and a leaky intake manifold gasket. Over the winter I replaced the gasket and of course the lope is
still quite evident. The motor has new plugs, wires, distributor, rotor, PCV valve. The ports on the intake where the EGR valve bolts on were thouroughly cleaned, and I also cleaned the EGR valve. The gasket around the MAP sensor was pretty ragged so I replace the MAP sensor. The Blazer runs a little better but not much I have checked for vacum leaks and found nothing. The cat had a rattle inside of it so I replaced that also.
I just checked the fuel pressure and it seems to be within limits although when at idle the pressure flucuates about 6lbs very fast.
Is this normal?
I also plan on doing a compression check this weekend.
Will it help to replace the fuel filter?
Does anyon have any suggestions. Thanks
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No 6 lb variation at idle is normal, look into this.

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98 Blazer Fuel Pressure Group: alt.autos.4x4.chevy-trucks Date: Thu, Jun 2, 2005, 5:58pm (CDT-2) From: snipped-for-privacy@usfamily.net The motor is a 4.3 with CSEFI system. Last summer the engine developed a lope and a leaky intake manifold gasket. Over the winter I replaced the gasket and of course the lope is still quite evident. The motor has new plugs, wires, distributor, rotor, PCV valve. The ports on the intake where the EGR valve bolts on were thouroughly cleaned, and I also cleaned the EGR valve. The gasket around the MAP sensor was pretty ragged so I replace the MAP sensor. The Blazer runs a little better but not much I have checked for vacum leaks and found nothing. The cat had a rattle inside of it so I replaced that also. I just checked the fuel pressure and it seems to be within limits although when at idle the pressure flucuates about 6lbs very fast. Is this normal? I also plan on doing a compression check this weekend. Will it help to replace the fuel filter? Does anyon have any suggestions. Thanks
Yes although if has a 6 psi fluctuation what is the actual fuel pressure? S cook
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Fuel pressure is 58-59 psi gradually moving up to 60 with engine on but not running.
The fuel pressure fluctuates rapidly between 52-58 or so with engine at idle.
With engine reved up the pressure has no fluctuation and will hold steady.
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