2002 1500 idle problem

I got a 2002 sierra 1500 with a 5.3l. I just replaced both catalytic converters and y pipe. After I did this, I am having a few problems. First, when slow down to park or at a stop sign the idle drops way down and it dies. I cleabed the throttle body, maf sensor, and ran a can of seafoam and a can of b12 chemtool through it. It did this for a couple of days and now when the idle slows down the "check oil pressure" light comes on before it dies. Then yesterday the "check oil level" light started coming on. Is this all related, would the low idle cause low oil pressure, any ideas where to start?
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I got a 2002 sierra 1500 with a 5.3l. I just replaced both catalytic converters and y pipe. After I did this, I am having a few problems. First, when slow down to park or at a stop sign the idle drops way down and it dies. I cleabed the throttle body, maf sensor, and ran a can of seafoam and a can of b12 chemtool through it. It did this for a couple of days and now when the idle slows down the "check oil pressure" light comes on before it dies. Then yesterday the "check oil level" light started coming on. Is this all related, would the low idle cause low oil pressure, any ideas where to start?
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Got any codes?
Is the IAC valve controlling idle?
Any vacuum leaks?

No engine codes and no vacuum leaks that I have found. I have cleaned the IAC and the TPS.

No engine codes and no vacuum leaks that I have found. I have cleaned the IAC and the TPS.

what is the idle oil pressure ? should be 40 psi area...

since you have no codes I would check the fuel pressure..should be 53-62 psi...if lower the fuel pump is probably going....

how many miles on this ? If you have over 150,ooomi when replacing the fuel pump replace the fuel relay . make sure grounds are clean and secure.

No engine codes and no vacuum leaks that I have found. I have cleaned the IAC and the TPS.

Cleaned does no say they are working.

May be fuel and oil pressure and scanner test time.