94 2.3 will fire but wont start

[RonD]

Ron, i double checked all of my timing marks and the position of the cranks and theyre dead on. i installed the timing cover and and the crank pulley to check TC and the marks are perfect. i did a wet test and the compression was 175-180 across all cylinders. i dont really care if the truck runs in prefect condition because its going to be used as a farm truck to run hay bales around and feed etc...

can you provide any info on the fuel system tests i provided? any advice on how to pinpoint my pressure leak?

thanks in advance

Yes, that compression is more like it, and that kind of jump wouldn't be just from oil.

On the fuel rail is the Fuel Pressure Regulator(FPR), it will have a vacuum line attached, remove this vacuum line and check it for fuel or fuel smell, if detected then replace FPR, it is leaking fuel and fuel pressure and that is ending up in the intake and flooding the engine.

The other end of the pressure part of the fuel system is the check valve on the fuel pump assembly, but lets test the fuel injector first, well first, AFTER FPR check.

Fuel injection computers all have a software to clear a flooded engine.
This can be used to test for leaking injectors.

Key on
Push gas pedal to floor and hold it there
Crank engine

With key on TPS(throttle position sensor) gets 5volts
With gas pedal to floor computer gets back 4.5+volts from TPS
This 4.5v tells computer to shut off injectors if there is no current MAF or CKP sensor data(engine is not running)
Cranking now would be with spark but no fuel injection.

Simple test would be to just crank engine, using above, if it fires now and then you have a leaking injector, engine should just be pumping air now, no fuel at all.

You could also disable spark, crank engine, as above, then pull each spark plug out and see if any are wet.

If you can't find the pressure leak at the engine end and there are no puddles of fuel on the ground then you will need to get to the fuel pump assembly, and most likely replace it.

 

[1994Ranger$$$pit]

oh you said engine check light. could you kindly point me in the direction of that thread or explain how to do it?

thanks again

I used this and another site that listed codes and this method of checking.

http://www.therangerstation.com/tech_library/OBD_I.shtml

*** Whoops,I see you got codes for the EGR.

 

[Scatman]

There is a possibility that the fuel is bad in the tuck but i dont think it is. the truck stopped running last friday and i bought it this monday so i dont think it is the fuel. im going to replace the fuel pump anyway so when i drop the tank ill pump the gas into a gas can and see if it looks bad or is separating or has water in it etc.

i did monitor the fuel pressure while cranking and it did even show on the gauge. the only way i could get any pressure to show on the gauge was to cycle the key from off to run 6 times. if i press the schrader valve with a screw driver and crank the engine it squirts out but its not like its under any pressure. im pretty familiar with how fuel squirts out of a schrader valve when its under proper pressure.

im going to run the tests and check the things suggested and ill let you all know what i find.

thanks for all the help

Edit: after reviewing the video i took of the fuel pressure gauge it did have pressure but only under 10 psi. probably around 6 or 7 psi.

 

[Scatman]

Update

checked the FPR. no fuel dripping or fuel smell

i got the truck to start by pressing the accelerator all the way to the floor. it turns over about 6 times and sputters to life. before running it any further i put her back together. pressing on the accelerator revs the engine up fine and it idles pretty smooth. do i need injectors?

also i think i may need a head as well because there is a loud intermittent tapping and squeaking sound and there is exhaust smoke coming out of the dipstick. when the time comes ill start another thread for that.

 

[black_demon69]

im going to replace the fuel pump anyway so when i drop the tank ill pump the gas into a gas can and see if it looks bad or is separating or has water in it etc.

remove bed and change pump that way much easier...

 

[RonD]

Update

checked the FPR. no fuel dripping or fuel smell

i got the truck to start by pressing the accelerator all the way to the floor. it turns over about 6 times and sputters to life. before running it any further i put her back together. pressing on the accelerator revs the engine up fine and it idles pretty smooth. do i need injectors?

also i think i may need a head as well because there is a loud intermittent tapping and squeaking sound and there is exhaust smoke coming out of the dipstick. when the time comes ill start another thread for that.

Engine should NOT start with gas pedal to the floor, there should be no fuel coming in to intake from the injectors.

Some thing coming out of the dipstick tube means PCV valve is probably blocked or off.

Squeaking and tapping from the top end is usually a bad rocker, can be fix cheaply if you catch it in time, if not then cam could be damaged.

 

[Scatman]

so i dont think the guy i bought the truck from was honest with me about how it stopped running. i tore the engine down to find the source of all the racket and here is what i discovered

the tappets on the cam are nearly flat. the valves dont seat properly. the cylinder walls are tapered. 2 main bearings are spun.

the injectors were the source of my fuel pressure loss. i pulled the fuel rail and turned the key to the run position and all 4 injectors dumped massive amounts of fuel.

bummer on the engine but i found one that i heard run in a rearend wrecked truck from a friend and hes going to pull the engine for me and sell it to me for $350.

i just want to thank you all for your help and advice. its much appreciated. Scatman out

 

[RonD]

Good deal on that engine.

All injectors being bad would be a odd occurrence...........that could be a computer issue.

Injectors get 12volts when key is on, computer grounds an injector to open it, so either all injectors are bad(could happen), or all 4 ground wires are shorted to a ground(could happen), or computer section that controls injectors is bad.

Judging by the other problems it might not even be the right computer in there??

 

[Dean Sibert]

I had an 89 that would turn over and try to start, but it wouldn't run. Anyway, we checked the continuity between the switch and the battery, and it turned out to be the switch itself. It would work in the start position but not the run. We installed a handy dandy toggle switch for the run position! worked great!