1980 368 motor non 8-6-4v

[nitinnelapudi2]

Having trouble with my 368...seems like its miss-firing. I had the intake manifold gasket, egr valve gasket replaced and it sounded alot better, but then it started to miss fire again (or so it seems) when I start it up in the cold mornings it idles but at one point it almost dies and then it catches its idle again. I am not mechanically inclined and I had my mechanic work on it. he did all that egr and manifold stuff to it. he said that he sprayed carburator cleaner around the engine and it seemed to idle perfect every time he did so he guessed there was some kind of vacuum leak thats causing the misfire. it runs but its eating gas like no other! the mechanic says he needs another $550 to fix. does anyone have any ideas?

[cadillac_al]

It would be nice to know how much vacuum it has; that's a simple test. I usually disconnect the EGR on cars that old (pre 85 or so) with no ill side effects. A really really worn carburator throttle shaft could leak a good amount of vacuum and still run fairly good. I hope the vacuum advance is working. How old are the spark plugs? Those old faithful AC's can get finicky after just a couple years. I started using Bosch Platinums in the early 90's and they always outlast the vehicle. They got a bad name with GM V6's and other waste spark igitions but are fine on old V8's. I've never heard of any intake gasket failures in the old Caddy V8's. Was it leaking or something? I guess I'm not big on preserving GM's vacuum maze they used back then. If it causes a problem I usually eliminate everything but dist vac advance and trans vacuum and brake vacuum of course. I hope the mechanic isn't just looking for income and actually has experience with old cars. Best of luck.

[elk9300`]

Get yourself some vacuum lines and start replacing. This doesn't cost $550. Trust me you would be better off.

Cars this old will have cracks where the hose connections are made. There are some hoses that when you squeeze them are like sponges or just crumble like powder. This is something that is pretty easy, I remember doing this on a car when I was first learning about cars as a kid. My dad would always be surprised at how well my cars ran when I got older and now asks me all of the questions....It's funny because he's the one that taught me how to change oil and shocks when I was 5 or 6....

This isn't like changing a head gasket and would probably get your feet wet....you have to start somewhere.

There is only one person in this world that I would never trust to do this and that is my wife. Anytime she drives my cars a check engine light always seems to come on and she has a "black" thumb in gardening...every plant dies. Don't ask me why

Your 80 Eldorado 368 should be fuel injected....I'm pretty sure
check the torque setting on all of the bolts removed for the intake. was the throttle body base gasket changed?, if not this could be where you have a vacuum leak. Your EGR is on top of the intake,check the torque on the two bolts and the vacuum line going into it.

Wherever you mechanic sprayed is where you'll find the problem...Why $550 I don't know????? None of the things that I mentioned should cost no more than $75.