1987 Chevy s-10 blazer running poorly

1987 CHEVROLET BLAZER

XIRONWORKER

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i have an 1987 chevy s-10 blazer with a carburated 283cid engine.fuel pump is in gas tank.my vehicle starts running poorly and i notice my fuel pressure regulator reads 2lbs so i turn it up to 4.5lbs runs great for a few miles.then the pressure reads 2lbs
i have to keep adjusting my fuel pressure regulator back up to 4.5lbs do you think my regulator or my in tank pump is going bad?

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Mar 27, 2012 at 9:14 PM

RASMATAZ

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75,992 POSTS

Check the actual fuel pressure with a gauge if its within specs-

Mar 27, 2012 at 9:42 PM

WRENCHTECH

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20,761 POSTS

If you converted that system from a return type system to a returnless using a regulator, you will just fry the pump. Those pumps aren't designed to run that way.

Mar 27, 2012 at 10:48 PM

XIRONWORKER

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4 POSTS

what pump system do you suggest i run?

Mar 27, 2012 at 11:56 PM

WRENCHTECH

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20,761 POSTS

It's a conversion that really should never have been attempted. It requires a different fuel tank and external fuel pump, preferably the engine mounted factory pump. These modifications aren't even legal to do.

Mar 28, 2012 at 12:02 AM

XIRONWORKER

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4 POSTS

thanks i will run engine mounted mechanical pump.

Mar 28, 2012 at 12:08 AM

WRENCHTECH

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20,761 POSTS

You need a different tank first.

Mar 28, 2012 at 12:09 AM

XIRONWORKER

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can i not just pull the pump put back the sender,then put an in line pump and a mechanical on the block.plus the regulator?

Mar 28, 2012 at 12:49 AM

WRENCHTECH

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20,761 POSTS

No, because the sender will no longer reach the bottom of the tank and you will have an extra line going into it. It also requires a vented tank which is illegal now. You can't just think you are going to "old school" and EPA certified car. The fines start at $2500.

Mar 28, 2012 at 12:54 AM