HELP 2.9 Running rich ?????????????

[Rangerdave73]

I have a '88 ranger 2.9 runs very rough burning tons of fuel and lots of black smoke I have replaced the o2 sensor and the FPR pressure seems good at 32 what next I need some help

 

[Tedybear]

Fuel pressure can be fine, however the internal parts of the regulator could still be bad. To check, remove the vacuum hose from the FPR and see if it has any fuel in it. If there's fuel in that hose? It'll suck raw fuel into the rear section of the intake.

S-

 

[Rangerdave73]

Fuel pressure can be fine, however the internal parts of the regulator could still be bad. To check, remove the vacuum hose from the FPR and see if it has any fuel in it. If there's fuel in that hose? It'll suck raw fuel into the rear section of the intake.

S-

it is a brand new FPR put it in today checked and its finewhat next

 

[AllanD]

Two things to check.

Pull the distributor cap and examine the wire from the pickup and make sure it isn't rubbing against the reluctor drum.

Next pull the passenger side kick panel and check the ground screws near the computer.

Next look at the engineering number on the PCM, if the number starts with E7
it's an '87 computer. you want one with an engineeering number of an E8, E9, F0, etc...

An '86-87 (EGR) computer will NOT run correctly in an '88-up ranger.

AD

 

[Rangerdave73]

ok PCM is E8 changed plugs wires cap rotor coil and adj. timing its better but still rich seems PCM is trying to comp for it runs great in driveway take it on the road runs rich and rough get in idle rpms up and down park it for acouple of secs still idle smooths out and seems fine again????????????

 

[Rangerdave73]

when comp. sets idle @ 1200 it runs smooth if it tries to lower rpms rough again

 

[Rangerdave73]

ok here is the code 96 "fuel pump secondary circuit/ high speed fuel pump relay open"
where is this relay and what is ya'lls opinion?

 

[Rangermilitia]

the fuel pump on the frame rail is the high speed pump. see if it is working at all or check the relay on the passenger side of the motor compartement. good luck

 

[Rangerdave73]

ok here's a list of what I've done:
fuel pump (pressure)
fuel filter
fuel pressure reg.
plugs +wires
cap+ rotor
coil
ign. mod.
pick-up coil
fuel pump relay
map sensor
o2 sensor
lock cyl
ign switch
injectors
tps sensor
coolant temp. sensor
starter
and an oil change
will most likely change temp sensor tomorrow to rule it out
what is left? it seems slightly better than the beginning. It is still very rich and rough intermittently. Bad enough that it gets about 8 mpg. Any new ideas or is it the computer?

 

[RangerJ]

ok here's a list of what I've done:
fuel pump (pressure)
fuel filter
fuel pressure reg.
plugs +wires
cap+ rotor
coil
ign. mod.
pick-up coil
fuel pump relay
map sensor
o2 sensor
lock cyl
ign switch
injectors
tps sensor
coolant temp. sensor
starter
and an oil change
will most likely change temp sensor tomorrow to rule it out
what is left? it seems slightly better than the beginning. It is still very rich and rough intermittently. Bad enough that it gets about 8 mpg. Any new ideas or is it the computer?

I had a similar problem except I did not have the black smoke. I changed the map sensor Vacuum Line and cured my problem.

 

[Beastly88]

i too have same problem but no black smoke
ive changed:
plugs-wires-cap-rotor
o2 sensor
fresh oil

 

[Rangerdave73]

ok noid light test seems to be fine. new computer did not fix it. I'm desparate what else could be the problem?

 

[RustedRanger]

I see how much stuff you have changed,I have changed a bunch of stuff also on mine trying to cure it running over rich at idle. During all this changing when did you do the plugs? Plugs was one of the first things I did but they didn't help much so I went on to other things it could be. I cleaned my IAC valve and it killed the plugs dead! And that was after putting in the new O2 sensor. If it runs real rich it can kill the new plugs and O2 sensor in a hurry as well as the oil so smell your dipstick to make sure you don't fill the oil with gas cause that can kill the motor in a hurry. My experiance over the last two months has me longing for something old with a carb and no computer! I'm thankful I found The Ranger Station!

 

[sjr53]

There should be an Orange wire from the wire harness near the distributor that gets grounded to the rear of the engine on the passenger side. If you lose ground on that wire, the engine will run very rich.

 

[Rangerdave73]

There should be an Orange wire from the wire harness near the distributor that gets grounded to the rear of the engine on the passenger side. If you lose ground on that wire, the engine will run very rich.

You are the winner fixed Thanks to all for your help