My 89 honda civic hatchback wont pass emissions. no check engines lights are on and no smoke coming out of the tail piple. it runs good. ive had hoses, pc valves and o2 sensor replaced. also had the throttle body gasket and rev hose replaced. i always have to tap the gas pedal when i start the car to keep it started. can anyone tell what might be causing the failed emssions?

SOURCE: 2006 pt cruiser idles high with no pcv valve hose connected

Replace the PVC valve, it's probably clogged.

SOURCE: 2002 Hyundai Sonata wont pass smog

CA you can take the car to a referree and get a one time waiver if you have spent a minimum of $450 on repairs not including smog fees. Gives you two years to get it fixed. Smog Referee Call Center
Toll Free: 1.800.622.7733
You can also sell the car to the state for "up to" $1,000

SOURCE: 1995 Toyota Camry - Code 71 - failed emissions tests

replace the EGR switching valve and have the machanic clear the engine check light. I think it should help

SOURCE: 92 Honda Accord failing Emissions

look at oxygen sensor.look at egr control solenoid.

SOURCE: 2000 Hyundai accent acts as if it is starving for

We've have the same problem with ours. We found the fuel canister needed replaces. It's mounted near the back bumper with straps. The part cost us about 125 bucks and was pretty easy to replace. The trick is to get the bolts out without snapping them.