Smoke when warm

[1993BlackSHO]

OK here is what is happening. I have noticed lately, and I mean only in the past week, when starting the SHO after only having the car off for a short time (10-15min), I have oil smoke out of the exhaust for a few seconds. If the car sits overnight, no smoke.

Dont think it can be valve seals, as it would be worse in the morning than a short sit of 10-15min. My wife told me it started smoking a few days ago while she was sitting in the drive-thru. I have yet to see it do it except on warm start-up.

Im kind of at a loss what could be causing this. I have to change my PS pump this weekend, so Ill be diving into the engine anyhow.

 

[1bad98SHO]

possible worn valve guides. When they get hot and expand and its sitting oil may be seeping by them but that would mean the valve seals would be bad as well. I have also ran across a bunch of motors that when the oil drain holes in the head get clogged up the motor will smoke alot.

 

[rubydist]

Are you sure its oil and not gas? If an injector doesn't quite shut off, you can get a flooding/smoke condition on that cylinder, which usually only shows up on relatively hot restarts.

 

[1993BlackSHO]

I was thinking possibly gas at first, but the smoke is light grey. If it was gas it would be much darker wouldnt it? I do have a loss of fuel pressure requiring me to prime the pump a few times on cold starts, but I assumed it was a bad check valve in the fuel pump.

I will have the intake off this weekend, is there an easy way to check the injectors while Im in there? I do have a spare set of injectors.

Edit: After doing a little more reading, Im starting to lean to the leaking injector. Anyone know how to check injectors for sticking?

 

[1993BlackSHO]

Someone has to know how I can check my injectors.

 

[TankII]

Run a bottle of Techron through with each tank for a few tank-fulls.

Also, check to see if there is a blockage on any of the breather tubes (PCV if yours is a CA car) or too much Carbon Build-up in the Intake Pre-heater assembly.

If it is oil, too much Crankcase pressure could display symptoms like that.

Oh, check the Fuel Tank Check-Valve as well.

TankII

 

[frosho]

Someone has to know how I can check my injectors.

I think the only way to do that would be yanking them and sending them out for testing/cleaning. I don't know of any bench-top tests.

 

[St Louis SHO]

Pull the rail, turn the key on and see if one drips... It shouldnt spray w/o cranking the engine.

 

[1993BlackSHO]

Thanks guys. Like I said, will be pulling off the intake this weekend anyhow, so I will do a good check of everything.

St Louis SHO, Thanks for that, should be pretty easy to tell that way if one is stuck open.

 

[1993BlackSHO]

Well Im even more convinced its fuel now. Sounds like one of my cats took a dump. Went out to lunch and heard a familier rattle. At least thats what it sounds like and ive never heard that rattle on my SHO before.

 

[1993BlackSHO]

Went ahead and picked up brand new o-rings today for the injectors. Since I'm going to pull them all out to check them, figured I might as well replace the o-rings.

Are both o-rings the same size? I got 6 sets of 2. They dont look any different. Just want to make sure.