Intermittent black smoke, rough idle, and smell of gun powder.

[genesiss]

2002 ford explorer. Issue with truck intermittently not starting every 3 weeks to a month. When issue begins truck was just turned off then back on and it sputters and stalls like its out of fuel. I waited an hour almost to the minute and then it starts but no sooner.

1. Cleaned mass air flow sensor
2. Cleaned IAC
3. Replaced camshaft and crankshaft sensor
4. Replaced ignition coil pack
5. No codes
6. Mechanic cannot find issue, its intermittent so it never happens in the shop

Within a day of replacing the ignition pack after some stop and go came out to vehicle after resting about 30 min and it had a rough idle and puffing out light amounts of black smoke with the smell of gun power from under the hood and the a/c will not work at all. Drove it to the auto parts store and they were clueless. Drove it home and turned it off, then back on and everything works! no rough idle, no black smoke and a/c works! Clearly too rich of fuel mixture but no a/c and it all clears up on a restart moments after being turned off?

 

[1Aauto]

Welcome to the site.

 

[genesiss]

Thank you tony

 

[RangerX]

Ouch! You DID post this in the New Member Forum, which is the forum to say hi, and have others welcome you...

Actual tech questions should be posted in the proper sections, in your case, the 2002-2005 Explorer forum.

Oh, and welcome.

 

[BrooklynBay]

Welcome to this forum! I've renamed your thread, and moved it into the 2001-2005 Sport Trac section. Do you have a check engine light? Did you have the PCM scanned for trouble codes?

 

[genesiss]

I apologize I was not aware that this was the wrong area of the forum to post. This issue is a little frustating considering no one knows whats wrong with the truck. No codes, no engine light, intermittent and I was told by the mechanic that my fuel pressure was tested although I am not sure if I should believe him reflecting back on the visit to his shop since I did not get the readings on the exact pressure from the fuel pump.

 

[BrooklynBay]

Check the engine coolant temperature sensor. This chart is one of the links in # 25 in my list of useful threads:

 

[bdmaash]

leaky injectors?
I have a post on this do a search (third selection from right up top)

 

[genesiss]

Ok but would leaky injectors explain why the issue is intermittent? Everything was fine after the vehicle was turned off then on. Also remember that before the coil pack was replaced the truck would not start at all for one hour exactly (give or take a minute) now so far the truck starts fine except for this one time with the black smoke rough idle and no a/c then its all good after turned off and back on again. I have also noticed very poor gas economy.

 

[bdmaash]

Ok but would leaky injectors explain why the issue is intermittent? Everything was fine after the vehicle was turned off then on. Also remember that before the coil pack was replaced the truck would not start at all for one hour exactly (give or take a minute) now so far the truck starts fine except for this one time with the black smoke rough idle and no a/c then its all good after turned off and back on again. I have also noticed very poor gas economy.

Restarts fine after shutting off = a possible leaky injector that hasn't had time to flood the motor yet.