1988 Chevy Silverado emissions failure nox

[quote:5a5294c750="jim_maryrose"]Engine Performance problem
1988 Chevy Silverado V8 Two Wheel Drive Automatic 180000 miles

I failed the emissions test the max reading for nox is 4.5 I failed with a 4.59. The truck had been parked for aver a year. I put some new gas in the tank. Should I clean the EGR or replace it? I don't know where to start.

thanks

Jim[/quote:5a5294c750]

Hi Jim,

Have you concidered doing a tune-up? Go ahead and clean the EGR Valve. You may also want to go ahead and change the O2 Sensors. You may also want to put some injection cleaner in.

Then go by you local auto zone and have them pull codes for you they will do it for free.

.