Cadillac Repair: 89 cad brougham 5.0 with 4 barrel carb, vacuum leaks, vacuum lines

Question
recent bought this cad for grand stepson, seem to run ok, same day he bought gas, and friend installed a cd player... after this the car was hard to start, idle rough , shift rough...they took car to cad dealer, dealer stated it needed carb rebuilt,,, total cost $2,000...... this is what I paid for the car.......we decline and drove it home, the car starts better now, seems to have enough power but has a rough an erratic idle, shifts at high rpms, the idle  will stay low for awhile, may die, restarts ok, idle may then increased,,,,,,,,,would this sound like a carb rebuilt deal as the dealer states. or maybe something less expensive to fix, we dont have cad type money, I put need pugs in when we got it home, they appeard to be really lean, really white in color on one bank, the other a little less but no carbon or black stuff, the exhaust seems to have a funny smell to it,, I think maybe the kid bought some bad gas but havent put any in it since I bought it home,, I replaced the air cleaner also..

does this 5.0 carb engine have this relearn idle process when the batt is disconnectd like the later models.?  I just read one post about that, if so then maybe this is the whole problem as I am almost sure the batt had been disconneted prior to the eng idle problem...  sorry to ramble on but would appreciate any advise, I can't pay $2,000 for a carb rebuild,

thanks,

Fred

Answer
There is a possibility that he got some bad gas. Fill the gas tank with gas and put a can of dry gas in the gas tank and see if it starts to improve after a few days.

When you get down to half a tank of fuel refill the gas tank and add another can of dry gas.


Take the air cleaner lid off and lightly put your hand over the top of the carb and by moving your hand closer and or further away from the carb and see if the idle starts to improve.

If it improves the idle speed, Spray all around the intake manifold for vacuum leaks as well as all the vacuum lines with carb cleaner and when you hit a vacuum leak the idle will improve and the engine will increase in rpm's.

$2,000 to rebuild the carb. I do them for $350.00. Unfortunately, I would have to have the car to set up the carb after the rebuild.


Let me know what you find and just check around some auto parts stores for a price on a rebuilt carb just for fun.

You will need the carb # which is stamped horizontally along the back of the carb and starts with 170.


let me know.

BTW: there is NO actual re-learn process like the newer cars. The relearn is done just by driving the vehicle.