1985 monte carlo Dieing out

[eaglei022]

I've been having this problem with my car where it runs rough at idle like hesitating and wanting to die out. I would lose power while accelerating but the car would never actually die out. Eventually my trans went out from having to slam on the gas to get the car to move.. I replaced the transmission and torque converter.

The car ran smoother but would now just die out when slowing down (pressing the brake) or coming to a complete stop. Also still would idle up and down in park.

I replaced spark plugs, spark plug wires, distributor cap and rotor, fuel injectors, fuel pressure regulator, and fuel filter to try and resolve this problem..

Fed up, I took it to a mechanic.. He's pretty good but man, $97.00 and hour. An expensive one. He set the timing for me because I had knocked it up a little thinking it would help it but didn't and the car was really rich. He also said the ignition coil was hardly giving a spark. So he replaced that and the car stopped the rpm flux at idle and it now doesn't die out AS OFTEN..

He told me the O2 sensor was testing bad because the readings were not changing and this was causing the rich run. Well at $97.00/hr I said I would change the O2 sensor myself.. I drove the car home and it ran pretty smooth, no more rough idle but I can still feel it wasn't 100%. It ran good for a few miles then while coming to a stop it died out again. I figured alright it's the O2 sensor no big deal. Started it back up and went on my way. It died again while stopping in the parking lot.. and (I do have a cold so it was hard to tell) I smelled a distinct electronic smell, the kind you smell when a capacitor blows or something. The car will now will not start. It turns over but not fire.

So Idk wtf is wrong with this piece now.. I'm going to take it back obviously Monday to see what the problem is but does anyone have any ideas what this sounds like??


He said the fuel pump tested correctly and I had the ignition module and distributor replaced two years ago so I can't see anything wrong with that...

Tomorrow I'm going to look for any blown fuses and listen for the fuel pump to turn on... Too dark out now to mess around with it.

Also, I changed all of the vacuum lines and sprayed some wd-40 around in the bay especially around the throttle body. Didn't hear a rev in rpms..

Thanks!

[maxwedge]

That quadrajet can be troublesome, it has internal electronic controls, no mixture adjustments to speak of, first thing that can be an issue, also a sticking or bad egr is another possibility

[eaglei022]

Originally Posted by maxwedge

That quadrajet can be troublesome, it has internal electronic controls, no mixture adjustments to speak of, first thing that can be an issue, also a sticking or bad egr is another possibility

It's fuel injected.

[rhandwor]

I would try spraying some carburetor cleaner around the edges of the intake manifold if it smooths out fix the leak in this area.
Egr problems will cause idle problems and shaking during driving.

[maxwedge]

You need to look at your engine again, a stock 85 Monte SS had a 4bbl Rochester, it never had EFI. It did have an o2 sensor and a basic ecu set up for fuel mixture.

[rhandwor]

Napa sells a basic carburetor kit and some parts. The dealer still should have the other parts.
All you need is a good re builder if you don't have an intake leak or EGR problem.
These had problems in the early 1990's.

[Bad86MonteSS]

i had a problem like this not too long ago with my 305 H.O in my 1986 Mo0ntye SS.try changing out the SPARKPLUGS.. cheap but may help it.mine runs better now.because that quadra"bog" can sometimes foul out the sparks plugs.My boss luckily figured it all out and you got my same issue..

[maxwedge]

Originally Posted by Bad86MonteSS

i had a problem like this not too long ago with my 305 H.O in my 1986 Mo0ntye SS.try changing out the SPARKPLUGS.. cheap but may help it.mine runs better now.because that quadra"bog" can sometimes foul out the sparks plugs.My boss luckily figured it all out and you got my same issue..

So after the carb fouled the plugs what was done to fix the root cause?

[palomba16]

Did you ever find out what the problem was? Mine was acting up the same way and come to find out it was a cross between a bad lifter and egr valve. Check your cylinder pressures.