91 Bravda won't start intermittently

[pm6163]

91 Bravda 155000 miles TBI 4WD.

Having this "won't start" problem for a while, now seems getting worse.

It won't start once a few weeks when I used to drive almost everyday, but will start easily if let it sit for a few hours. This is situation a few months ago.

Now, I don't drive this Bravada that much, when try to start once a few days, it won't start usually. After I managed to get it started, it will re-start ok then. But after a few days of not driving, it won't start agian.

I heard that the engine of this model gets flooded easily, I tried pressing down the gas pedal for a couple of minutes with switch ON, then start. But still very difficult to get it started, only success a few times.

What do I have to check? How to use the "start fluid" to see if it will start?

[Chris Stewart]

Allright!!! Another most cool 1st year of the Bravadas.
Does the engine spin over good or grunt like the battery's down?

[pm6163]

It is cranking good and strong, I can crank it for many times, but the engine just won't start.

[Chris Stewart]

Can you smell raw gasoline at the tailpipe after trying to start the motor?
If so, we have a spark problem. If not, with the aircleaner off, try pouring 1/4 cup gasoline down the throttle body then try to start. If it runs a few seconds then quits, we have a fuel problem. Keep your battery charged up good, a run down battery kills starters & alternators. Getting a boost for 20 minutes without trying to start the Bravada motor will charge it up nicely.
Let us know.

[pm6163]

I wasn't able to start in the previous 2 days, now I can start right away. A puff of light blue smoke always come out the first when motor is started, same happened today. I checked the tailpipe, I think there is strong smell of gasoline when motor is running, after a short while some white thin smoke comes out, and the gasoline odor is gone, in a little longer, the white smoke is gone too, we had rain this morning, humidity is high, that is what cause the white smoke, I guess.

Do you think the spark plugs may need to be replaced? Thanks.

[ericn1300]

Originally Posted by pm6163

I wasn't able to start in the previous 2 days, now I can start right away. A puff of light blue smoke always come out the first when motor is started, same happened today. I checked the tailpipe, I think there is strong smell of gasoline when motor is running, after a short while some white thin smoke comes out, and the gasoline odor is gone, in a little longer, the white smoke is gone too, we had rain this morning, humidity is high, that is what cause the white smoke, I guess.

Do you think the spark plugs may need to be replaced? Thanks.

the blue smoke at startup is normal on these engines. you might have a leaking fuel injector dripping gas into the engine when off causeing a flooding like symptom. check your oil for gasoline, the oil level will actually go up if gas is leaking down thru the pistons.

[Chris Stewart]

When you turn the keyswitch on (not start), can you hear the fuel pump running near the gas tank every time?
Sorry for all the questions, just trying to get more specific.

[pm6163]

Originally Posted by Chris Stewart

When you turn the keyswitch on (not start), can you hear the fuel pump running near the gas tank every time?
Sorry for all the questions, just trying to get more specific.

Yes, I can hear the fuel pump running everytime even when the engine won't start up.

[Chris Stewart]

I agree with Eric on the blue smoke...valvestem seals don't last forever but it doesn't hurt anything as long as it clears up in a coupla minutes.
Since you hear the fuel pump, the throttle body systems are real reliable and the weather has cooled off lately, I leaning toward an ignition problem. A bad coil gets worse with heat. I heard a little buzzing sound under the hood with the engine running and traced it to the ignition coil.
What are the chances you got a shot of water when you last fueled up?

Eric, how'd yours act when the distributor bearing was going out?

[pm6163]

I was able to drive the car for a few times yesterday, meaning on & off a few times without any problems. This morning, engine won't start, I press the gas pedal down while key is in ON for 1 minut or so, engine seemed want to start, it used to be just cranking, engine is not starting, this time, engine want to start but could not, you know what I mean? After a few tries of gas pedal down while in ON, and pressing gas pedal up and down while starting up, I managed to get the engine running. Hope the description is clear enough for you guys to know what is going on, thanks for help.

I will be out of town for a whole week, will check your responses at that time, thanks.

[Chris Stewart]

After it starts, is the "Service Engine Soon" light on?

[ericn1300]

Originally Posted by Chris Stewart

Eric, how'd yours act when the distributor bearing was going out?

cold engine miss fire caused a code 44 from raw fuel being pumped thru. started no problem but felt like it was running on 5 cylinders

[pm6163]

Originally Posted by Chris Stewart

After it starts, is the "Service Engine Soon" light on?

No, no SES light at all times.

[Chris Stewart]

Ok, no Check Engine light, intermittent start w/ pedal stomping...we need a new start.
Don't pump the gas pedal, try to start the engine but don't turn the motor but about 5 seconds, when it won't start, smell the exhaust pipe for raw gasoline fumes.

[pm6163]

Originally Posted by Chris Stewart

Ok, no Check Engine light, intermittent start w/ pedal stomping...we need a new start.
Don't pump the gas pedal, try to start the engine but don't turn the motor but about 5 seconds, when it won't start, smell the exhaust pipe for raw gasoline fumes.

I will try the following:
Don't pump the gas pedal, switch to ON for 5 seconds, then try to start, when it won't start, smell the exhaust pipe for gas fumes.
Correct me if I am wrong, thanks.