« on: Jul 01, 2013, 08:12:30 PM »
BigMike showed me your situation and I'd like to offer a suggestion.
My guess is that the EGR diaphragm is either opening too far or is flowing too much air.
Remove the small vacuum hose that goes to the top of the EGR valve (essentially disabling the EGR) and try it again. You wouldn't have noticed this with your webber because the webber does not provide a vacuum signal to the EGR valve.
You may be missing the orifice (a small crimped metal washer) located between the EGR and the head) and too much exhaust is entering the intake. With the EGR disabled, it should run like a top. Remove the EGR valve and replace that orifice.
You can also troubleshoot this by checking the temperature of the 90-degree elbow connecting the EGR to the intake manifold. It should be very hot due to how much exhaust is getting past it.
Let me know what happens with the vacuum source disconnected from the EGR valve, thanks.
Marlin
![](https://board.marlincrawler.com/Themes/MCI_V3C/images/ip.gif)
Logged
BigMike
likes this
1980 Toyota - 1997 3RZ-FE 2.7l Engine, Turbo R151F 4.31:1, Triple Turbo Marlin Crawler Billet (2.28x4.70x4.70) = 1,148:1 Crawl Ratio, Marlin Crawler Twin Stick and Short Throw Shift Kits, 30mm H/D Output Shaft, High Angle Drive Lines, 5.29:1, ARBs, High Pinion Front, 25mm HD Billet High Steer Kit, 6 Pin Locking Hub Bodies, 86+ Wide Rear End, V6 3rd member, Chromolly Axles all around, 37" IROKs with Beadlocks, York onboard air - Rollbar air tank, Premier Power Welder, Marlin Crawler 4" USA-made Leaf Springs, Bilstein Shocks, et cetera....