White smoke......then......nothing

[fa1rch1ld]

1994, 3.0, 2wd. It was sitting for a few years. Completed a complete tune-up and passed California smog easily. It does get a little hot going up hills and sitting with the AC on, although the AC doesn't work very well. Figured it just needs a new thermostat and housing, and a radiator flush.

Driving on the freeway today. A big puff of white smoke. Thought for a minute that something was on fire or something was overheating. Then, nothing. Drove around for another hour. No issues. No white smoke is coming from the exhaust; it looks clean and clear. After getting it home, it got a chance to cool down a bit. Started it up. A puff of white again. Then nothing. Drove it around for an hour; it was fine, with no smoke. Let it sit tonight and see what happens tomorrow. Advice would be appreciated.

 

[ShhhhhDougsHere]

I'm just a novice around here, compared to most of these guys.

However you said it sat for a few years.
My thoughts are maybe there's something in the exhaust system that is getting burnt up a little bit at a time.
And that's what the smoke is coming from.

I may be very wrong however.

The white smoke is coming out of the exhaust right?

 

[fa1rch1ld]

I'm just a novice around here, compared to most of these guys.

However you said it sat for a few years.
My thoughts are maybe there's something in the exhaust system that is getting burnt up a little bit at a time.
And that's what the smoke is coming from.

I may be very wrong however.

The white smoke is coming out of the exhaust right?

On the freeway, hard to tell, but I'm assuming, yes. When parked and started, it was definitely from the exhaust.

 

[ShhhhhDougsHere]

When you was on the highway did you really get into it and blow it out real good?

 

[fa1rch1ld]

When you was on the highway did you really get into it and blow it out real good?

Nah. Was just cruising.. The smoke didn’t happen till about putting 200 miles on the truck.

 

[ShhhhhDougsHere]

Maybe you might want to blow it out the next time? You never know it might help things out.

However you don't want to go to hard on it either.

 

[RobbieD]

Driving on the freeway today. A big puff of white smoke. Thought for a minute that something was on fire or something was overheating. Then, nothing. Drove around for another hour. No issues. No white smoke is coming from the exhaust; it looks clean and clear. After getting it home, it got a chance to cool down a bit. Started it up. A puff of white again. Then nothing. Drove it around for an hour; it was fine, with no smoke. Let it sit tonight and see what happens tomorrow. Advice would be appreciated.

Your truck is listed as an automatic trans.

Check to see if the transmission's vacuum regulator is leaking fluid. Pull the vacuum line and look for signs of ATF leaking past the regulator diaphragm. Also, keep an eye on the ATF level on the dipstick.

One of my trucks had the exact same symptom. Turned out that he regulator was weeping fluid, and when enough collected in the vac line the motor would pull in a good gulp, and make a spectacular cloud of white smoke, just driving along. It was a for-sure head-scratcher until I stumbled upon the cause.

 

[fa1rch1ld]

Your truck is listed as an automatic trans.

Check to see if the transmission's vacuum regulator is leaking fluid. Pull the vacuum line and look for signs of ATF leaking past the regulator diaphragm. Also, keep an eye on the ATF level on the dipstick.

One of my trucks had the exact same symptom. Turned out that he regulator was weeping fluid, and when enough collected in the vac line the motor would pull in a good gulp, and make a spectacular cloud of white smoke, just driving along. It was a for-sure head-scratcher until I stumbled upon the cause.

This makes sense. The previous owner mentioned on long drives, especially driving up to the mountains from the city he’d have to put a little transmission fluid in occasionally, and I can’t see any visible leaks. I’ll check out the vacuum line.

 

[Uncle Gump]

That would be the vacuum modulator...

It tells the transmission what type of load the engine is under.

Seems like a reasonable place to start looking as RobbieD has already stated.

 

[RobbieD]

That would be the vacuum modulator...

It tells the transmission what type of load the engine is under.

Seems like a reasonable place to start looking as RobbieD has already stated.

Yep, that's it.

Modulator.

That's the ticket!

My CRS strikes yet again . . .
. . a mind is a terrible thing to lose.

 

[Uncle Gump]

Yep, that's it.

Modulator.

That's the ticket!

My CRS strikes yet again . . .
. . a mind is a terrible thing to lose.

Do you know where I set my welding glasses? I can't find them anywhere!

 

[pjtoledo]

Do you know where I set my welding glasses? I can't find them anywhere!

no clear vision, eh?

 

[ShhhhhDougsHere]

@pjtoledo it's not that @Uncle Gump can't see them.
It's that they are on top of his head and HE forgot that's where HE put them last.