caprice running horribly

[dschmitta]

hey,

I have a 1988 caprice classic brougham. It seems to have a few problems, don't know if relatd or not. always runs with a miss and low power. when slowing down to stop, shudders and will not downshift until almost at complete stop. shakes at idle. when going up through gears if i need to give it throttle, car shakes horribly until i manually use gears to downshift. also, fuel tank seems to hold alot of pressure and will also make a loud thumping noise, even when car is shut off! please help. Thank you

P.S. seems to run worse the hotter it gets

[j cAT]

Originally Posted by dschmitta

hey,

I have a 1988 caprice classic brougham. It seems to have a few problems, don't know if relatd or not. always runs with a miss and low power. when slowing down to stop, shudders and will not downshift until almost at complete stop. shakes at idle. when going up through gears if i need to give it throttle, car shakes horribly until i manually use gears to downshift. also, fuel tank seems to hold alot of pressure and will also make a loud thumping noise, even when car is shut off! please help. Thank you

P.S. seems to run worse the hotter it gets

what engine is engine is in this vehicle...? what is the idle RPM ? you got tools to work this ?

this may be vacuum leaks..check with a vacuum guage , the vacuum , when looking for leaks..under/at the carb/TBI you will find most vac line failures...carb cleaner over time eats at the rubber..also any carb operating devices could be leaking...
measure the plug wire resistance. remove the distributor cap and check for arcing ..

plug wire routing on vehicles this old is usually not correct..make sure these wires are routed so they do not get damaged from being too close to the heat of the manifolds...

EGR valve may be leaking/operating out of correct range this would mess up the fuel air ratios..

[dschmitta]

Originally Posted by j cAT

what engine is engine is in this vehicle...? what is the idle RPM ? you got tools to work this ?

this may be vacuum leaks..check with a vacuum guage , the vacuum , when looking for leaks..under/at the carb/TBI you will find most vac line failures...carb cleaner over time eats at the rubber..also any carb operating devices could be leaking...
measure the plug wire resistance. remove the distributor cap and check for arcing ..

plug wire routing on vehicles this old is usually not correct..make sure these wires are routed so they do not get damaged from being too close to the heat of the manifolds...

EGR valve may be leaking/operating out of correct range this would mess up the fuel air ratios..

it is the 305 engine. i do think the idle is set up too high, i'm also having an issue with he engine running after shutting off. I do have tools, hopefully the ones I need. Thanks for info

[Blt2Lst]

Originally Posted by dschmitta

I have a 1988 caprice classic brougham. It seems to have a few problems, when going up through gears if i need to give it throttle, car shakes horribly until i manually use gears to downshift.

Your shifting problem is most likely a TV cable that is not adjusted properly. Do a search here for the adjustment procedure.
It sounds like you have other issues also, when was your last complete tune-up (plugs, wires, cap, rotor, fuel + air filter, timing checked)?
Start with the basic stuff first.

[j cAT]

Originally Posted by dschmitta

it is the 305 engine. i do think the idle is set up too high, i'm also having an issue with he engine running after shutting off. I do have tools, hopefully the ones I need. Thanks for info

after you get the engine running properly then post back with any others issues you may still have...

the idle should be 650 rpm in drive vehicle stopped..

one componet that can cause too much fuel to get injested with this engine would be the cannister purge valve ..this multi hosed device can get internal rupture and then liquid gasoline will be directly dumped into the intake by way of the vapor purge hose...

the vacuum lines at the base of the carb should have not fuel in them.or smell very strongly of fuel..