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Update on '78 Monte Carlo you guys have helped with

Okay, you guys gave me some good direction on my problem and I've done a lot of reading and looking at diagrams. I think that port is intended to be open.

I started suspecting the EGR possibly so I felt through the back of it and it is definitely stuck open. The diaphram never moves hot or cold, throttle open or not.

Also, I noticed a small amount of gas on the outside of the fuel pump. So I drained some oil and there is a small amount of gas in it. I'm theorizing that when the car wasn't running, the fuel filter gummed up and that put a strain on the fuel pump, causing it to start to fail.

I'm going to replace the EGR and the pump and I'll report back with my results, if anyone is interested.

Thanks for all the help, everyone!

Reply to
JK
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Please do.

I am very curious what you find since I have a year older Caprice.

Snip

Reply to
charge

I'll add here what I found in the Chilton manual just in case the problem is not fixed with what you found.

The Chilton manual supports the TCS post. Vacuum advance to the distributor is controlled by a transmission control solenoid TCS which opens and closes to allw/disallow vacuum to the dist advance, no advance in lower gears just advance in high gear. There is a cold overide switch , the TVS which I suspect is the one you have with the 3 ports. Setup appears to be that vacuum to dist is either

  1. from carb to TCS to TVS middle port and out top port of tvs to dist. This vacuum, when passed by TVS depending on temp, will be on/off based on TCS or 2. from carb to TVS lower port and out top port of tvs to dist. This will be path based on TVS temp (cold path I assume)

If yours is like this then at high temp the vacuum for advance would need to be at the centre port (from TCS) which appears to be miss> Okay, you guys gave me some good direction on my problem and I've done

Reply to
Ken Hilson

Reply to
Ken Hilson

Reply to
Ken Hilson

There is no vacuum port left open on purpose on any car that I have ever seen. An open port kills everything else on that line.

Steve B.

Reply to
Steve B.

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