Help! I failed my emissions, so i have 30 days to resolve this. The NOX was way high, and we found that the EGR valve wasnt working. turns out, that was fine, the solenoid was fine; there was no vacuum pressure. We checked the tubes, all clear. We checked the computer, and it says that everything is fine. The filter is clear. What could possibly be wrong? Again, no vacuum going to the EGR. Help!
2007-05-11 10:06:34 · 1 answers · asked by Anonymous in Cars & Transportation ➔ Maintenance & Repairs
EGR valves that are vacuum operated are usually controlled by a thermostatic valve that is mounted in the intake manifold or block coolant passage and only allows the EGR to work once the engine has warmed up. A vacuum hose routing diagram under the hood should show you this setup buy may not show you where the thermo valve is located...just follow the vacuum line from the EGR to this thermo valve and replace that valve. It could also be that the vacuum hose is pinched or broken or came off so check for vacuum at the thermo switch also with a warm engine. You could also bypass the thermo valve temporarily and just run a vacuum hose from the carb directly to the EGR once the engine warms up and see what the test results are then.
2007-05-11 10:24:33 · answer #1 · answered by paul h 7 · 0⤊ 0⤋