1990 Caprice Classic problems

[OrngCaprice]

I have a 90 Caprice 305 TBI, I got it from my grandfather (orig owner) its got 55k miles on it and its starting to have some issues. This mainly happens on warmer days, or it takes longer to happen on cold days, once the car has reached operating temp. it wants to stall at lights (mainly after I exit the hwy) it acts like its a standard and doesnt want to go into neutral. Also once its been driven for a while (30min or more) it wants to die if it sits at idle for longer than about 45 secconds. If it dies at idle it'l usually take a couple minutes to want to start back up, and when it does start back up when I start driving it changes gears VERY quickly, like its into 4th gear at 20mph. Someone told me this could be the lockup soleniod in the tranny not working right...but could that make it stall at idle??

I have NO clue where to start.


Also recently it died at a light and wouldnt start back up, so I got a new battery, and had the alternator checked and it checked out OK. I diddnt think it was the starter because I can see the motor trying to kick over, the pullys on the accessories turn about a half turn so I know the starter is trying, BUT all the lights in the car go completely out when it tries to start. I dont think its a fuel or spark issue, because then I would think it would turn over just not fire. Can the starter short out so it would pull a lot of current to make my lights dim, but not start the car?


Thanks for all the help!!!!

[silicon212]

The transmission issue could be a lockup converter issue only if it seems to want to stop the engine when you get to a light or otherwise stop the car.

The main transmission issue sounds like a TV cable adjustment. First thing is where I scare you - running it out of adjustment like this can lead to a quick death for the transmission. Now is where I make you feel at ease - it's very simple to adjust it, and to borrow a GEICO quote - it's so easy a caveman could do it. You will see the TV cable where it connects to the TBI lever - it's the one on the bottom (it pulls out when you press the gas). There is a "D" shaped tab pointing upward on the cable, just behind the bracket the cable attaches to. Press this in hard with your left thumb, then with your right hand, pull the cable back as far as it will go (toward the firewall), and let go of the tab with your thumb. Using a screwdriver, open the throttle all the way. You will hear a rapid clicking sound - may even sound like you're stripping the teeth off a plastic gear - but once you do this and let go of the throttle, the cable is properly adjusted.

The stalling in traffic, slow starts and poor performance when warm all point to an injector issue - possibly clogged or dirty. You can run a couple of tankfuls of gas with each tank receiving a bottle or two of injector cleaner. If this doesn't do the trick, you can have the injectors serviced. Also, replace the fuel filter. This will be bolted into the steel line just ahead of the tank on the bottom of the car.

[OrngCaprice]

Originally Posted by silicon212

The transmission issue could be a lockup converter issue only if it seems to want to stop the engine when you get to a light or otherwise stop the car.

The main transmission issue sounds like a TV cable adjustment. First thing is where I scare you - running it out of adjustment like this can lead to a quick death for the transmission. Now is where I make you feel at ease - it's very simple to adjust it, and to borrow a GEICO quote - it's so easy a caveman could do it. You will see the TV cable where it connects to the TBI lever - it's the one on the bottom (it pulls out when you press the gas). There is a "D" shaped tab pointing upward on the cable, just behind the bracket the cable attaches to. Press this in hard with your left thumb, then with your right hand, pull the cable back as far as it will go (toward the firewall), and let go of the tab with your thumb. Using a screwdriver, open the throttle all the way. You will hear a rapid clicking sound - may even sound like you're stripping the teeth off a plastic gear - but once you do this and let go of the throttle, the cable is properly adjusted.

The stalling in traffic, slow starts and poor performance when warm all point to an injector issue - possibly clogged or dirty. You can run a couple of tankfuls of gas with each tank receiving a bottle or two of injector cleaner. If this doesn't do the trick, you can have the injectors serviced. Also, replace the fuel filter. This will be bolted into the steel line just ahead of the tank on the bottom of the car.

Thanks for the reply, I'm going to try the "TV cable adjustment" ASAP! Also if it was a lockup converter issue, would that cause the car to switch gears too quickly?


As for the stalling being related to the injectors, I'm really leaning away from it being that or a fuel issue, as I've had it checked out and fuel filter has been changed as well as I've watched the injectors during regular revs and they spray a nice V shaped spray with no concentrated spots, and no matter what I try and do (rev the engine etc.) I cant keep it running once it starts to die. I've also had the catalytic converter checked out, all the plugs and wires changed the distributor rotor changed (because I thought the electronics attached to the rotor were shorting out or having problems when they got too hot) I changed the fuel filter, got a new alternator, changed the tranny fluid and filter. Any other thoughts?

[silicon212]

Originally Posted by OrngCaprice

Thanks for the reply, I'm going to try the "TV cable adjustment" ASAP! Also if it was a lockup converter issue, would that cause the car to switch gears too quickly?


As for the stalling being related to the injectors, I'm really leaning away from it being that or a fuel issue, as I've had it checked out and fuel filter has been changed as well as I've watched the injectors during regular revs and they spray a nice V shaped spray with no concentrated spots, and no matter what I try and do (rev the engine etc.) I cant keep it running once it starts to die. I've also had the catalytic converter checked out, all the plugs and wires changed the distributor rotor changed (because I thought the electronics attached to the rotor were shorting out or having problems when they got too hot) I changed the fuel filter, got a new alternator, changed the tranny fluid and filter. Any other thoughts?

1. The TV cable adjustment is what determines shift points. "Short-shifting", or "stack-shifting", chiefly the act of banging through the gears in rapid succession as you state before 20mph is a great indication of a maladjusted TV cable. In this stack-shifting mode is where you are susceptible to fatal transmission damage.

2. My gut feeling, which is driven by experience, tells me you have some sort of fueling issue. Have you put a pressure gauge onto the diagnostic port? Should read between 9-12 PSI. If it's lower, and you're sure you've replaced the filter, it might be time for a new pump. Any MIL indications (i.e. Service Engine Soon light)? One possible issue that's not fuel-related could be the module inside the distributor.

[OrngCaprice]

Would the TV cable make it shift like that all the time, because it only does it when its been driven at operating temp for atleast a half hour.

I changed the fuel filter about 2 months ago, as well as the entire distributor assembly (including the rotor shaft) because I thought the same thing, that it might be bad electronic parts on the distributor.

I occasionally throw a MIL for EGR valve, usually while driving on the highway...could it possibly be getting stuck open and cause the car to die?