My truck failed Air Care on the drive test. The Hydrocarbons and CO was too high. I've had it troubleshooted and took care of all the codes. I had a small leak in the Thermactor Air By Pass Valve vacuum diaphragm and changed the whole valve. My hydrocarbons and CO is still high. The Thermactor system still seems to have a problem. The Haynes manual that I have says that when the engine is warmed up, to shut the engine off and hook up a vacuum guage to the Air Bypass Valve, start the engine and the vacuum should hold for between 100 and 180 seconds, mine only holds for 34 seconds and then releases. The EEC is showing no codes and all the sensors seem to be working OK. PLEASE can anyone help??? I'm at my bloody wits end trying to figure it out, and so is the garage.
Thanks to anyone that replys.
Tom ... Old Bottomburp@aol.com
Have you tried cheating yet???
Make another appointment for the test. Run the fuel down to 1/8 of a tank. Just before you get to the test facility, add 1 gallon of methyl hydrate(sp)(gas line antifreeze) to your tank.
That's a common trick in Ontario for us poor folks to get a pass on the emmissions test here. Not knowing your test system, I have to ask...what do you have to loose?
After the test, you'll want to fill the tank right up to reduce the % of M.H. in the fuel.