Don Hause needs advice
 

I recently bought a 2002 Chevy Tahoe LS 5.3 V8 Flex Fuel with 226000 miles on it. I am getting 5 miles per gallon of gas. Have installed new fuel regulator, plugs, wires, fuel injectors, oxygen sensors, air filter and Valve springs on number 1 cylinder. Still missing on number one cylinder. Diagnostics still suggests replacing valve springs. Heavy smell of raw gas. During Idle it misses several times. HELP ME SOMEONE. PLEASE.

I highly recommend Mustang Automotive in Friendswood. James is an exceptional mechanic and they are as honest as can be. I'm not affiliated other than a satisfied customer who won't let anyone else touch my vehicle. Good luck.

Have you had the cylinders compression tested? You could have a hairline crack in the cylinder maybe?

Is it one of those with the fuel pressure regulator inside the intake?

Actually compression test is a good idea, maybe a cylinder leak down test while you're there.

My brother had a similar truck that gave him a fit. Dealership kept resetting the CEL without fixing anything. They eventually found the regulator leaking inside the manifold (not viewable from outside). It was fouling the cylinder closest to the leaking regulator, with liquid fuel. One plug always wet with fuel, had less than 50k and still under emissions warranty.

That year you should have a CEL telling you something. Never heard of one diagnosing weak valve springs, but my knowledge is ancient.

Thanks R.I.D.E.
Installed new external fuel regulator. Will check repair Manuel about internal regulator. Compression checks out excellent all the way around.
Thanks for your advice. Don't know what a CEL is though. Best wishes for happy travels from water weary Houston Texas.

CEL is check engine light

Adding an external regulator IF the original is internal, will not resolve the issue.
It should be diagnosable as a fairly fast leak down, after shutdown, on an added pressure gauge. Normally the pressurized fuel rail will hold pressure for a decent amount of time, of course when there is a leak (even one you can not see), the pressure drop will be almost instantly obvious with complete loss of pressure in around 5-15 seconds.

That's your gas smell (its liquid, not sprayed out of the injector and added to the nearest cylinder, with out any chance to be atomized with ambient air.

Similar to using an old pump oil can with gas, spraying it into a vacuum port on the manifold, flooding out the closest cylinder.

I would follow LDB's advise if you don't know what a CEL is. Most decent shops will tell you what's wrong and the cost to repair without spending a lot of money and that SOUNDS like where you have been in this process. Pretty strong recommendation from a fellow borad member.