84 fiero blue/white smoke when running (Page 1/1)
MoonZombie APR 21, 12:38 AM
Hey everyone I just bought my first fiero for $600. It's starts but when its started it billows blue/white smoke out of the engine compartment. I have put seafoam in the gas tank and new oil in it aswell. I have bought a value cover gasket, cause I was told by a firend that was the problem, but I thought you all would know a bit more. Any help appreciated.
Mike in Sydney APR 21, 01:31 AM
Welcome to the forum. Next time, can you provide a bit more information about your car? What's the mileage & Engine Type? Does it smoke only on start-up or does it smoke continuously? Your experience with engines, etc? That will make it easier for folks to help you.

There are many possible reasons for the smoke. Before you get into any analysis or solution mode, you should do a tune up. Change the plugs, air filter, & PCV valve. Adjust the timing following the proper process. When you remove the plugs you will get a good idea of possible issues that you may have. I suggest that you do a compression test at this time, too.

After tuning, you can "read" the smoke colours. If the smoke is white and smells slightly sweet, you should check the head gasket(s) for leaks. This is indicative of antifreeze getting into the cylinders during combustion. Check the spark plugs, too. Really clean plugs could point to the area where the gasket has failed. White smoke that goes away when the engine is warm is likely just condensation in the muffler that is "boiling" off. This is nothing to worry about unless it is constant while running.

White smoke also could be the result of a failed valve cover gasket. Clean the engine well and look for obvious leaks from under the valve cover(s). Pay attention to the areas over the exhaust manifolds.

If you get blue or grey smoke on start up but it goes away soon after check your valve stem seals. If they've never been changed, after 38-years there's a good chance that they're part of your problem.

Blue or grey smoke on start up that doesn't go away is likely worn rings, cylinder bores. Get out your wallet because you're probably going to have to rebuild the engine. This would be the time to consider an engine swap depending on how much you are prepared to spend.

Black smoke on start up and while running is likely due to a overly rich condition. Check your fuel injection system or carburettor.

There are a bunch of folks on the Forum that can provide more input and help.

Good luck with your diagnosis. I hope the cause isn't terminal.

[This message has been edited by Mike in Sydney (edited 04-21-2022).]

Dennis LaGrua APR 23, 08:07 PM
Blue smoke usually means that the engine is burning oil. White smoke usually related to water or condensation coming from the engine or exhaust.
Here are the things that you need to do. First off do a pressure test of the cooling system. If it holds pressure thats good but if it doesn't then a head gasket failure could be the problem. You may then need to pull the head and install a new head gasket
If the engine continually blows blue smoke that could mean that the piston rings or valve seals are worn.
Do a compression or cylinder leakdown test. If the cylinders test within spec then its likely the valve seals and that is not a hard replacement. On a 38 yr old engine I would replace them anyway.
Unfortunately a engine diagnosis and a remedy cannot be suggested by discussion here. You will need to TEST, TEST and TEST . Also remember your engine is very OLD and do not be disappointed if it needs major internal repair. The good news is that most Duke parts are still available and most anything can be repaired with an amount of time and money.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

theogre APR 24, 01:20 AM
Coolant Pressure Testing for Fiero https://www.fiero.nl/forum/Forum2/HTML/145505.html
⚠️ Warning: Coolant can leak "internal" in the engine.
First is pull spark plugs and keep in order.
Look at them.
Is #4 or others are cleaner then rest?
#4 can suck coolant when intake manifold gasket is bad. If true need FEL-PRO MS90563
But Others often mean head gasket is bad etc.

⚠️ Warning: Clean plug holes, loosen plugs ~ 1 turn, clean again. Loosen make more crap loose that fall into the engine when you don't clean again.

If burning oil...
Can be 1 or more of...
Valve stem seals
Valves and guides worn
piston rings
engine worn
etc.

⚠️ Warning: Burning either can cause Catalyst and O2 sensor failure. Dead Cat can cause engine problems or burn down the car.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave