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200 auto shaking - cid not mph

505 Views 2 Replies 3 Participants Last post by  65coupei6
This is so typical, first time I remember something in the old forum to look at, the old forum has just been made obsolete.
I remember that there was a thread about carb changes in 200cid and another about sprag. So I have to ask again.

Symptons: 200cid C4 is shaking badly from idle and shaking decreases when rpms go up. This happens both on standstill neutral and while driving. Idle is acceptable, that's why I suspect the carb. However, we tried different carbs without any change to this shaking. We have tried different distributors with and without various vacuum connections.

The converter was off, can that be damaged during installation so that it would give shakes?

I know nothing about automatics so if you think that could be the culprit, please, be spesific.
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I'd make a strong bet for a vacuum leak. Check the hose connections from the carb area to the vacuum modulator. The modulator is on the bottom right side of the C4 trans. The hose often works loose from age. I suggest replacing that hose.

Check the PCV hose from carb to valve cover and check the PCV itself. It should rattle. Sometimes they get gummed up inside and don't work right even though you think its okay. It wouldn't hurt to replace it (cheap $2-3). Especially check the gromment in the valve cover that the PCV goes into. Pep Boys has them but I don't know the part number. Just take the old one with you and match it up at the store.

Cap, points, rotor are good? Spark plugs and wires good?
Check for those nasty vacumm leaks. Also make sure you do not need a tune up. Plugs, cap, rotor, points. Make sure your timing is correct. If you need some carb and tuning info click on my sig below for my Inline page.
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