88 ford ranger 2.9 V6 black smoke, loses power?

Question

i have an 88 ranger 4x4 .... and i been having this problem recently .... when driving along ..... it starts dying off like as if the fuel filter was clogging or something .... and starts putting out black smoke out of the exhaust ... and losing power like its trying to die off .... but .. then it picks back up the power and goes ..... it does this quite a bit ..... my cheap diagnostic says the EGO sensor isnt switching but .... i also had this problem with my 2 wheel drive 4 cylinder engine and ... i changed the sensor in that and it didnt make much difference ..... any ideas?

Answer 1

check the egr and see if it's sticking, usually wd40 can fix it

Answer 2

Remove the vacuum line to the fuel pressure regulator and check for fuel in the line. Be careful not to spill any gas on any hot parts causing a fire. Over time it has been known that the diaphragm inside the regulator can fail causing raw fuel to go directly into the intake causing a rich condition. That would also explain the problem with the ego sensor. If that is the problem make sure you change you oil as it will be fuel contaminated.

Answer 3

Try changing the air filter. Black smoke is a sign of too rich a fuel mixture, and a plugged air filter is the same as running on "Full Choke."

Answer 4

Sounds like the fuel pressure regulator is busted, too much fuel pressure, or engine running too cold. Usually the reg. goes bad, if its that make sure to change the engine oil

Answer 5

check the spark plugs first check to see if there is any oil on them. if their is you'll probably need a compression test done to see if your seals are ok. if that is not the problem check your fuel pump. It is really hard to get to because it is on the tank. Good LUCK!!!