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Hi guys....Anyone know about checking the condition of the EGR valve? I have a new one on the engine[ 2 months old] and it is vacuum attached to the 'thermal vacuum switching valve', which is tapped into the intake manifold at a water jacket. Then the other side of the VSV goes to the high side of the carburetor vacuum port[above the throttle butterfly]. Thus...the VSV and the EGR only get vacuum when the throttle is advanced. My problem is if I connect the vacumn line from the EGR valve to the VSV and then the VSV line to the carb, the engine runs real rough and the power brakes don't seem to work properly. I can tell by the 'feel' of the brakes. Also, I can only pull up about 8-10 inches of vacuum on the vacuum gauge. Then, when I remove the EGR vacuum line from the VSV---Presto, I get a gain of about 10 inches vacuum [totalling up to 20 inches] , the engine runs much better and the brakes operate as usual. I've read several 'tests' to be made to check out the EGR but they don't seem to apply to my case. As you stock LUV owners know, the darned EGR is stuck way up under the intake manifold and it is real trouble to take out. I'd like to be able--since mine is new-- to figure it out without removing the EGR. Any suggestions?? Thanks....Don

My guess is a vacuum line connected wrong somewhere. There should be no vacuum at the EGR valve with the throttle closed at idle. Try disconnecting the hose at the EGR valve to verify.

So yesterday, I removed the EGR valve and tested it with a hand vacuum pump and it opened about 1/4 " at 10 inches of Hg. The hole in the unit is is about 3/8" diameter. Next I cleaned it out well and checked all the passages. I reinstalled it and same thing happens all over. I am having a bit of an idle problem [that I brought up here a couple of weeks ago] that is dripping gas at the primary venturi. So the idle is high-- maybe allowing the egr valve to become engaged. In fact, I checked the vacuum at the lowest idle I could attain and there was about 11" Hg. So with the system all back together,I'm still having the same troble as my above post mentions. I have a new idea though. Could it be possible that the 2 months old egr valve be opening too much and allowing too much exhaust gas into the cylinders. Maybe it is broken the 'other way' Thanks...Don Egg, When I remove the vacuum line going to the egr and it is not operating at all, I get a good 20"Hg on my vacuum scale and it picks up about 500 rpm---runs good.....Think I'll order another EGR Valve

Dripping gas at the primary venturi and the EGR opening too early points to the same problem. The throttle is open too far at idle. Two things happen when the throttle is open too much--the added airflow causes the fuel to start flowing/dripping and the throttle starts to uncover the vacuum port to the EGR causing it to open. What could cause all this? I suspect ignition timing is too late. 6 degrees BTDC at 800 rpm with vacuum line to distributor disconnected. Do this first and if no better then you may have plugged idle passages inside the carb (idle circuit not working).