Barely Running!

[Vanner1993]

1986 ranger 2.9, I got stuck on a trail last night, and I got it out with a pull. Truck does not want to run after that, sounds like a tractor and only will run with pedal to the floor. The oil pressure it all the way to H on the gauge when cold. Only has fuel come out of the test fitting when running, there is no fuel coming out just with key on. Just runs like putt..putt..putt...like an aggressive cam in a 2 cylinder..help!

 

[hopster]

the pump is only on for 2 seconds after you turn the key on so you will have to cycle it a few times to get it to squirt out. pull the vacuum line off the fuel pressure regulator and see if there is fuel in it if so bad regulator. also check spark on all cylinders. then get back to us with results and we'll go from there.

 

[Vanner1993]

Spark plugs 5 were black and smelled like gas, 1 was clean, which must of been the one cylinder running. There was some fuel when I pulled the line off the regulator, would it shoot out of there if I ran without the line on?

 

[Duane867]

Thats a vacuum line used to actuate the diaphragm inside the regulator.
If you take it off and discover its leaking then the diaphragm is torn. Its possible you will just get more of the same. A little fuel dripping out. Or you could get a squirt.
In either case you need a new one. Leave her parked and visit the parts store.

 

[Vanner1993]

Well it is backfiring through the intake, all the plugs are clean still (after I cleaned them), new cap and rotor, it will only run by cranking with gas to the floor and clutch to the floor, but seems to be running on one cylinder. Even with foot to the floor it is no more then 100 rpms, I am getting air, fuel and spark, would a sensor cause this?

 

[Vanner1993]

And the truck will not move under it's own power, not even enough to run with clutch let out in neutral. Should'nt the truck run with the vacuum line off the regulator? or is vacuum required to the regulator to get fuel in?

 

[Duane867]

Did you change the regulator yet ?
Check out the IAC yet ?

 

[Vanner1993]

The regulator is good, pulled number one plug out and got it to top dead center. Distributor is on the spot, no play between crank and cam so not the timing chain, Crank it, just cranks, has fuel pressure. Crank with gas pedal to floor, barely runs and only seems to be firing one cylinder and dumping gas out the exhaust, let off pedal and dies. All spark plugs are black and smell like gas again after cleaning them. Ran codes, temperature sensor(computer one) changed it, still no good.

 

[Duane867]

NO sir. The regulator is not good by your own findings :

There was some fuel when I pulled the line off the regulator, would it shoot out of there if I ran without the line on?

Any wet fuel in that vacuum line means the regulator is bad. Period.
Its dumping gas because the fuel regulator is not regulating fuel flow.
Its letting it all pass through like a flood and the only reason your able to start it at all is because the butterfly is all the way open to half ass match the gas being dumped in it.
Thats why your seeing raw fuel out the pipe.

 

[Vanner1993]

I went out today, tried to start it nothing, foot to the floor and fired right up. It has a VERY SEVERE misfire. I changed the fuel regulator and nothing changed. I kept it running with foot on pedal while my dad pulled plug wires and the only power difference that was noticed was when the #1 plug wire was removed and put on. 4,5,6 nothing at all changed. Plugs are just getting soaked with fuel. The truck sounds like a tractor. For some wierd reason it has a throttle response now unlike this past weekend. The engine is just not firing with the fuel or something, can the computer cause this? The engine smooths out when throttle is brought up. If I snap the throttle it just winds up and is like a serious delay. But slowly accelerating is smooth, then when I let off sounds once again like a tractor and dies.

 

[Spott]

Well, get back to the basics. For combustion, you need fuel, air, and spark. It's unlikely you're being denied air, so work with fuel and spark.

Pull each plug, one at a time, ground the side of the plug against the body/block/etc, and see if you're getting spark for each cylinder. If not, check wires, points, rotor, etc. If you're getting spark at all, in any cylinder, it means the ignition circuits work.

Check fuel. Make sure you've got about 40PSI of pressure at the fuel rail. Unplug each injector wire in turn, seeing if it makes a difference. Double check each connector and make sure it's making good contact. If you're desperate, pull each injector and run it (carefully) checking for function and a good fine mist.

Finally, check compression in each cylinder.

Once you've done all this, you may have found the problem. If not, at least you know what the problem isn't.

Let us know what you find,
Spott

 

[Duane867]

And check your IAC.

 

[Vanner1993]

All cylinders are getting spark, fuel is 40 psi, the only thing I have not checked is compression, but they all push air out the spark plug hole when turning over.

 

[Spott]

Well, it's unlikely that compression is a problem, they haven't all just failed to hold compression all of a sudden.

Like Duane867 suggests, check your IAC, and your air filter. There's surely a logical reason that it's not running, you just have to find that reason.

Spott

 

[Vanner1993]

Air filter is new, just went out today, colder than yesterday and it won't start. Want to but won't. What is the IAC? Will the TFI do this?