Tiny
POCOLACHRISTIAN
  • 1999 CHEVROLET SILVERADO

Hi. I keep getting codes P0171 and P0174. I have a 99 chevy silverado 5.3L. I already cleaned MAF sensor and replaced air and fuel filter and put new pcv valve and put new plugs and wires on it. I can't hear any vaccum leaks either so I'm puzzled what could cause this. Any help would be great. Thank you.

SPONSORED LINKS
Do you
have the same problem?
Yes
No
Friday, March 8th, 2013 AT 7:31 AM

1 Reply

Tiny
ASEMASTER6371
  • EXPERT
  • 25,511 POSTS

Cleaning mass air flow usually does nothing as it cannot be cleaned of all debris.

Most likely causes, vacuum leaks, low fuel pressure, pcv valve, mass air flow failure. The long term trims need to be monitored with a scan tool.

My bet is on a vacuum leak at the intake

Roy

SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Friday, March 8th, 2013 AT 10:18 AM

Please login or register to post a reply.

Related PCV Questions

2001 Chevy Silverado Pcv Valve,does It Have One And...

Engine Problem 2001 Chevy Silverado V8 Four Wheel Drive Automatic 70000 Miles I Just Ask This Question But Since I Am New I Do Not...
Asked by P1M1S1 ·
1 ANSWER
2001
CHEVROLET SILVERADO

I Have A 2002 Chevrolet Silverado 1500 4.3 Liter. I...

I Have A 2002 Chevrolet Silverado 1500 4.3 Liter. I Was Driving And The Cel Came On And Started Flashing Then The Truck Bogged Down And...
Asked by bubbanlisadaniels ·
1 ANSWER
2002
CHEVROLET SILVERADO

2000 Z71

Hello, I Have Talked To You Guys A Couple Days Ago While Im Setting In Idle My Rpm Will Go Up To 1000 And Then To 500 And Back Up. I Have...
Asked by joey74 ·
1 ANSWER
2000
CHEVROLET SILVERADO

Where Is The Location Of The Eec Evaporative Emission...

I Am Getting The Code Po440 When I Scan The Truck
Asked by barbara1963 ·
1 ANSWER
1999
CHEVROLET SILVERADO

Recommended articles