[24v Dohc]

Have 03 Taurus 3.0 24 v dohc duratec
Recently replaced plugs now onto the 3rd set. When I changed them the car ran great for about 20mins now it won’t stsrt unless given gas and won’t stay running unless you’re giving it gas. It bucks real hard and has thick white smoke coming from exhaust also inside you can smell something strange like exhaust/gas? Engine kinda sounds like a rotary engine when you can keep it running for a short time. New plugs only have 342 miles on them until this happened.

 

[Jeff K]

Not sure where you live, but are you sure the thick white smoke the standard heavy white smoke when the weather is cold and also humid?

Thick white smoke not due to atmospheric conditions is usually associated with burning coolant due to a failed head gasket, cracked head or cracked cylinder wall. Does the exhaust smell kind of like burned sugar? If so, the engine is getting coolant in the combustion chamber. However, blown head gaskets are VERY VERY rare on the Dutatec, as are cracked heads, etc.

If it werent for the smoke, I would say you loosened a vacuum line during the plug change and the vac line has now fallen off creating a large vacuum leak.

 

[chartmaker]

Have 03 Taurus 3.0 24 v dohc duratec
Recently replaced plugs now onto the 3rd set. When I changed them the car ran great for about 20mins now it won’t stsrt unless given gas and won’t stay running unless you’re giving it gas. It bucks real hard and has thick white smoke coming from exhaust also inside you can smell something strange like exhaust/gas? Engine kinda sounds like a rotary engine when you can keep it running for a short time. New plugs only have 342 miles on them until this happened.

Why were you replacing plugs. DOHC will need one set of plugs in a life time unless you use Autolite and as my case they last about a year and ruin the wires.
So you need to go back over your work and see if you left a hose off or something else has gone wrong. I pull the intake manifold to do the rear plugs or the coil which might as well replace while doing wires. Coilpack crack and fail. Plugs good for 100K and coil is good for 100K.
-chart-

 

[24v Dohc]

Have 03 Taurus 3.0 24 v dohc duratec
Recently replaced plugs now onto the 3rd set. When I changed them the car ran great for about 20mins now it won’t stsrt unless given gas and won’t stay running unless you’re giving it gas. It bucks real hard and has thick white smoke coming from exhaust also inside you can smell something strange like exhaust/gas? Engine kinda sounds like a rotary engine when you can keep it running for a short time. New plugs only have 342 miles on them until this happened.

Not sure where you live, but are you sure the thick white smoke the standard heavy white smoke when the weather is cold and also humid?

Thick white smoke not due to atmospheric conditions is usually associated with burning coolant due to a failed head gasket, cracked head or cracked cylinder wall. Does the exhaust smell kind of like burned sugar? If so, the engine is getting coolant in the combustion chamber. However, blown head gaskets are VERY VERY rare on the Dutatec, as are cracked heads, etc.

If it werent for the smoke, I would say you loosened a vacuum line during the plug change and the vac line has now fallen off creating a large vacuum leak.

I will look into the vac lines. But no cracked heads or anything like that. Coolant is also fine. I will add I just replaced the plug wires and now it starts right up but dies instantly.

 

[24v Dohc]

Why were you replacing plugs. DOHC will need one set of plugs in a life time unless you use Autolite and as my case they last about a year and ruin the wires.
So you need to go back over your work and see if you left a hose off or something else has gone wrong. I pull the intake manifold to do the rear plugs or the coil which might as well replace while doing wires. Coilpack crack and fail. Plugs good for 100K and coil is good for 100K.
-chart-

I had motor craft plugs in it then switch to autolite and the ends of the plugs are white/black on the front 3 by the rad and the back 3 by the firewall are all burnt/soaked in gas these are the ones that only have 342 miles on them but I also pull the manifold. No check engine lights on either. The old wires didn’t look bad at all and I replaced them and it will now fire up for about 10seconds and die out.

 

[Jiyu Shugi]

Obviously fouling the plugs. White smoke is usually oil (if it's not coolant). Rings totally worn out? Valve guides totally worn out?
Do a compression check.

 

[24v Dohc]

Obviously fouling the plugs. White smoke is usually oil (if it's not coolant). Rings totally worn out? Valve guides totally worn out?
Do a compression check.

I know about fouling plugs and rings yes. Last week there was oil in the tailpipe and intake as well but this week no oil in either.

 

[james27613]

Check your PCV valve, if it is bad that can cause plugs to foul.

 

[Cheeseless2]

Have 03 Taurus 3.0 24 v dohc duratec
Recently replaced plugs now onto the 3rd set. When I changed them the car ran great for about 20mins now it won’t stsrt unless given gas and won’t stay running unless you’re giving it gas. It bucks real hard and has thick white smoke coming from exhaust also inside you can smell something strange like exhaust/gas? Engine kinda sounds like a rotary engine when you can keep it running for a short time. New plugs only have 342 miles on them until this happened.

That thick rubber elbow, under the upper plenum that leads to the hidden PCV valve, gets weak and cuts off vacuum. Buy the IMPROVED version, out for some YEARS now. It has strengthening ribs on it, to prevent collapsing. Motorcraft created it, Aftermarket slowly caught up with Ford. Make sure it has the ribs on it, other style NO GOOD. Also, like others said already, replace any weak, soft vacuum connections---anywhere.