help help help blinking check engine light

hey guys i need some help im going crazy chasing this problem in my truck.its a 01 suburban 1500 has the 5.3 4x4 lt model.ive been getting this check engine llight blinking for a long time very erratic at all diiferent times.it comes on blinking and the truck will start running like crap.at first i swapped the airflow meter.didnt work.it feels like it starts starving for fuel but if you smell the exhaust it smells rich.the codes i used to get would point at the 2 sensors on top of the fuel pumps so i changed out the pump with a brand new module.didnt work then i changed all 4 02 sensors no luck there so i finally had the cats punched out since they say thats why the light would blink meaning your gonna danage the cats.still no luck but its was much more drivable when blinking after the cats got punched.so these codes are what im getting after all of the above work let me know where you guys think i should go next. and very sorry for such a long post but i wanna get this fixed.

sorry forgot the codes po 154,po 171,po 174,po 300 and po 453 and po 141

thanks VJ

ur not going crazy, ur just throwing parts at it without proper diagnosis. what was the fuel pressure? did u check the fuel pressure regulator? unless you eliminated the rear o2 sensors, that check engine light is gonna be on since the cats were 'punched' out.

That's called shotguning parts or a waste of cash lol

well when i punched the cats i tried the oil foulers on the 02 i dont no if they are working but i dont think thats causing the problem.as far as throwing money at it.the codes pointed to the sensors on the top of the fuel pump module so i figured instead of changing the sensors ill just buy a pump cause the truck has over 300k on it and i have no idea whats ever been replaced.i think the scan tools will show me fuel pressure wont they?havent changed or checked the pressure regulator.ive got a 2005 sierra 2500 6.0l in my garage lq4 motor that im building for my swap do they use the same regulator if i need to ill steal it off that motor.the problems driving me nuts cause im nervous about doing my wap caue im afraid these gremlins will carry over to the new install.if i have the codes shut off thru the tune will that affect the way my truck runs or does my custom tune overrides that?

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Originally Posted by vj72ct

well when i punched the cats i tried the oil foulers on the 02 i dont no if they are working but i dont think thats causing the problem.as far as throwing money at it.the codes pointed to the sensors on the top of the fuel pump module so i figured instead of changing the sensors ill just buy a pump cause the truck has over 300k on it and i have no idea whats ever been replaced.i think the scan tools will show me fuel pressure wont they?havent changed or checked the pressure regulator.ive got a 2005 sierra 2500 6.0l in my garage lq4 motor that im building for my swap do they use the same regulator if i need to ill steal it off that motor.the problems driving me nuts cause im nervous about doing my wap caue im afraid these gremlins will carry over to the new install.if i have the codes shut off thru the tune will that affect the way my truck runs or does my custom tune overrides that?

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get a fuel pressure guage and check it. putting parts on based on the dtc's you have is not fixing the truck the right way. a bad regulator can cause the o2 codes, fuel sensor codes, and so on. im not saying thats ur fix.... all im saying is you need to properly diagnosis the truck. start with the basics on what an gas engine needs to run; air, fuel, spark, and compression. go thru each and make sure they are correct. damn now im typing too much!

Vaccume leak?

I had a broke wire inthe harness for my injectors that did that to be4, but I agree chck fuel pres.

Spark plugs, coils, injectors, fuel pressure regulator, vacuum leak, compression. Lotta stuff can cause a missfire.

thanks alot guys ill throw the fuel pressure gauge on it and also check for vacuum leaks around the intake gaskets see if i find anything there also.thanks for your help ill keep ya posted!!