black smoke

Some of the causes of black smoke would be the fuel pressure regulator and the mass air flow sensor. More likely the sensor than the regulator. Also, when mass air flow sensors go out of calibration, they do not always generate a trouble code.

Just a few quick ideas.

do you think that maf would make the tranny act like its slipping and the check engine light flashes a bunch and i cant turn the overdrive off when its acting up its really weird

There are a lot of possibilities here. Bad signals from the MAF can "confuse" the computer, causing many possible "reactions." The computer decides which gear to activate in the transmission based on inputs from sensors. It calculates for engine loading, RPMs, road speed, etc. If a sensor gives a reading that is not correct, but not out of range, it can cause the computer to select the wrong gear. This can give the impression of slipping. If the computer selects a higher gear than it should, it can seem very sluggish, like if you put a manual transmission in high gear at 5mpn. If this happens with an automatic, the torque converter is then the only reduction available, so it will rev up to stall speed without making the car move as it should.

There is also the possibility that you have more than one problem, in which case the two symptoms may be unrelated.

Start with the problem that is the most important, and then work from there to see if other problems exist.

As with any diagnosis, do not overlook the basic needs of an engine - fuel/air mix, spark, and compression. If one goes wrong, the other two will not matter. Too many people start out by guessing and changing parts. This is an expensive way to effect a repair.

A live reading from several sensors and a fuel pressure gauge while it is acting up would be a big help. If you have a scan tool with this capability or a friend that has one, that would be a good place to start. Good luck.

I'm having the exact problem with my 1995 Ford Explorer XLT. I had a tune up done and it stopped blowing black smoke out the exhaust and stopped shaking. All was fine. Then I turned off the truck and back on again and it started right back up. I then replaced the fuel pressure regulator, vacuum lines since they were brittle but the problem is still there. I have the fuel pump and will do that next but I can't get any codes. Not sure if the computer went bad. Not sure how to check that. Any advice?

Hello, I'm Danny.
If you want to check codes for an OBD1 system here is the tutorial:

https://www.2carpros.com/articles/ford-lincoln-mercury-obd1-1995-and-earlier-diagnostic-trouble-code-definition-and-retrieval

After reading, scroll the page to find Ford.Hope this helps and thanks for using 2CarPros.

I have an OBD1 reader but I can get any codes. Even with different machines.

Hello again,

Is the check engine light on ? Here is a tutorial for black smoke:

https://www.2carpros.com/articles/engine-black-smoke

Hope this helps and thanks again for using 2CarPros.

Yes, the check engine light is on. Has rough idle and black smoke. Burning fuel fast too.

Hello again.

I do know that auto parts store AutoZone will check your codes for free.When you get the codes- get back to us with the code number and we can then help you properly diagnose the issue.Thanks again for using 2CarPros.

my 94 ford explorer when started will idle low 200 - 600 for a second then turn off if i keep my foot on the gas in netural it will stay running then will run fine for a few then start back to running rough around 200-600 rpms then die unless i keep my foot on the gas in netural idleing around 900- 1500 rpms when idleing but not all the time black smoke (siut) out of the exhaust ?? plz help!!!!

Is the check engine light on? This happens when cold? Or all the time, even after re starting a hot engine?

yes the light is on when the problem occurs it does it most the time cold or hot it will restart right after it dies . this problem just started a few days ago

First step is to read the codes, Autozone does it free, then post codes found here. Or try to read the codes yourself: Jump the two termnals shown together and turn key to "ON" and count the flashes... a 22 will flash as 2 flashes then a short pause, then 2 flashes, if more than one code is stored, the pause will be longer. The codes will display three times and end with 11 or 111. Write them down and post here. First do this with the key on engine off, then again with it running.

okay i will try that .
here is a few things ive done so far (i have a autoshop next door that helps me out ) ive cleaned the egr vavle , idle control vavle/mortor cleaned intank manafold, air censors were cleaned , and that about it

Things to look at, O2 sensor VERY important, Coolant temp sensor,, this acts kind of like a choke for fuel injected cars. Black smoke = too rich, too much fuel.
With 200,000 plus miles I would replace both! After parts replacement remove the negative battery cable for 5 minutes to clear the KAM(keep alive memory) or the computer may not know the new parts are there...

i changed my tranmission fluid and now there's black smoke coming out of the exhaust and it dosen't ldle right since i changed the transmission fluid. It's also putting. It has 195,000 miles and a V6 4.3 liter engine. Can you offer any advice?

changing the fluid shouldn't have caused this problem , im wondering if you may have bumped or pulled a wiring harness by the dipstick , sounds like iac , check the wiring and let us know , check everything close to where you were working up top

jim

My 1994 explorer engine light is on.. I drove it like this for some time. The other day while entering the hwy from the ramp the truck would olny go 35 mph.. Prior to this when on the hwy at 65 mph the engine light would go on and off periodically.. When the light would come on you could hear a slight thump (like it was shifting gear).. when turned over the exhast lets out a puff of black smoke.. If placed is park while running and the gas pedal is pressed black smoke come out of the exhast..

Pull the code/s from the computer-black smoke could be the oxygen sensor/s not adjusting fuel demand. excessive fuel pressure due to pressure regulator/MAF sensor.

1994 ford explorer. idles rough and there is black smoke from tailpipe.
Please help

Sounds like its running too rich

Probable causes of an engine running rich are as follows:

1.Excessive fuel pressure can be cause by restricted fuel return line
2.Defective Oxygen Sensors.
3.Leaking injectors and fuel pressure regulator.
4.Coolant temperature sensor out of calibration.
5.Restricted air intake system.

Truck starts fine but when i step on the gas it hesitates like it's not getting enough fuel. Have changed all sensors except o2. Still have black smoke coming from tailpipe so will check the above. Could this be a fuel pump problem?

Check the fuel pressure with a gauge if its within specs-Injector/s and fuel pressure regulator could be leaking-investigate

Shakes or Wobbles problem
1993 Ford Explorer V8 Two Wheel Drive Automatic

My ford explorer for the last month has been messing up. It blows out black smoke when you start it up, it idles up and down until it warms up all the way, it idles up and down when I am stoped at a light or stop sign (like it wants to move forward but can't), and it leaks oil from the front. One mechanic told me that it might be the egr sensor (or erg....can't remember) and another told me that it's the mass air flow sensor.

IF the black smoke is coming from the exhaust, that tells me it is running rich (too much gas). Make sure the air filter is clean and not blocked. Also, has the check engine light come on? To me it sounds like there is a problem with the ambient temp sensor. It is a sensor that tells the computer how warm or cold it is outside and the engine temp. Based on that info, the computer determines the air fuel mixture needed for the engine to run properly. Now the idle problem you are experiencing can be caused as a result of the temp sensor or a bad throttle position sensor. As far as the EGR, it would most likely cause a rough idle, but not what you described.

LEt me know if the check engine light has come on.

Joe

Smells problem
1993 Ford Explorer 6 cyl Two Wheel Drive Automatic

My car is Running Rich and blows out black smoke. And sometimes shuts off when stopped. Ive cleaned out numerous things that I was told try to clean out by the engine. Ive also used fuel cleaner. And the problem still exists. Is there anything I should try?

Try replacing the ambient temp sensor. It tells the computer the outside temp and engine temp. As a result, the coumputer tells the injectors how rich to make the mixture. For example, if the computer thinks it -40 degrees, it will make it run really rich.

A friend and I just finished replacing the heads on my sons 93 explorer after he overheated it and fried the head gaskets.... The head job itself seems to be a success as the vehicle has better power than ever and runs smooth... once we disconnect the air flow sensor. With it connected it idles very rough and stalls frequently. It also blows clouds of black smoke. When disconnected it idles perfectly, runs smooth and there is just a very slight blackness to the exhaust. We were thinking maybe a plugged catalytic converter but there is no loss of power when accelerating hard while driving.
Any input would be greatly appreciated. Thanks in advance

Are you refering to the mass air flow sensor? Also, the black smoke indicates a rich fuel mixture. If you are refering to the MAF, try cleaning it. They make special cleaner for them you can get at any parts store.

Also, check the converter to see if it is getting red hot.

Let me know what you find.

Joe

I have a 1993 ford explorer with almost 98000 miles on it. I recently put my. car in the shop for a muffler. Well before I put it in the shop grayish smoke came out of the exhaust pipe and the car would wobble when I came to a complete stop. This is when the smoke would start. I figured the problem would of been fixed with the new muffler but the proble now is worse. The car wobbles and rattles/shakes when I come to a stop but it does it harder and now black smoke is pouring out of my tail pipe. What can this be and can it be fixed or is it time to trash my car.

Actually, the grayish smoke tells me the coolant may have been getting into the combustion chamber via a bad head gasket. However, black smoke indicates a rich fuel mixture. Has the check engine light come on?

By the way, if the body is good, 97k miles isn't even broken in yet.

Let me know.
Joe

in the morning when i turn my truck on it runs good. 5 min later it starts idling and black smoke comes out the exhaust ,smells. it stays like this all day, i already changed the IACV and the sensor but still same problem. when im driving it runs good then it feels like it pulls back and the check engine light turns on. Then 10 seconds later picks up speed and the light goes off keeps on doing this while driving . check engine light turns on and off while driving also. dont know if its the EGR or something else, i went to get the computer read but they cant read it. Vehicle would not respond. check engine light if off when i need it for obd reader.please help.

Possible causes include a bad O2 sensor, excessive fuel pressure (bad fuel pressure regulator or plugged return line), leaky fuel injectors, dirty air filter or restricted air inlet, or a defective coolant sensor that prevents the engine management system from going into closed loop mode.

so the oxygen sensor can also cause black smoke and idling?

A bad oxygen sensor may prevent the system from going into closed loop, and usually causes the fuel mixture to run rich causing an increase in fuel consumption and emissions.

I have changed all the sensors except the fuel pressure sensor and still get the part time miss and black smoke from exaust. I have put code reader on and codes are 41 and 45. can you tell me what else to change or replace. also put in new plugs and coil pack

41- The o2 sensor is reading lean or not switching.
45 is self diagnostics.
Does your truck have a MAF sensor? Look for vacuum leaks. Does the truck miss at idle or under load?

Changed the MAF sensor. and it misses under a load. Idles fine

Have you done the wires? Could be an ignition miss since it is under load. Might even be a weak injector or two

yes, change the wires and plugs. replaced all but the fuel pressure regulator and the IAC. Has me stumped