gdowle

Helllo i have a 1994 f150 4.9 straight 6 engine. cylinder 2 has a spark and fuel but wont fire at all. here is a list of the things ive done

compression test = ok
new rotor
new cap
tuned ignition timing
new plugs
swapped leads round but problem stayed in cylider 2
swapped injectors round but problem stayed with cyl 2
had the error codes read and it came up with "spout connector open curcuit". been told that error is there because of the missfire.

does anyone know of anything else before i check lobes on cam shaft or take piston out?

is there anything electonic ive missed that would cause this?

apprectiate any help

thanks

Good old Bill

Pull of the valve cover and check valve action. If the intake valve works you will have compression, but if the exhaust doesn't open the engine will not fire on that cylinder. Could be a flat camshaft, hopefully its just a dropped push rod. Another symptom could be some slight backfireing in the intake.

gdowle

well i took rocker cover off and made sure push rods and springs looked good. used remote starter and span her over and all looks good. i swapped the injector again just incase and still the same. sprayed intake cleaner down inlet manifold aswell.

got some errors on the scan tool tho. im pretty sure they are all there because of the misfire and not causing it but i could be wrong.

CODE 10 - snap throttle

173 - ego not switching bank 1 rich

213 - spout ckt open

411 - rpm out of spec - normal crb idle

538 - cylinder ballance test - fail restart

45 lbs of fuel pressure at idle

so now im lost any ideas?

Just call me Sean

iTrader: (1)

The spout connector is the little plastic plug near the distributor that is unplugged when ignition timing is set. The computer is saying that it is unplugged. With it unplugged the computer is unable to advance timing, so it always runs at the base timing. You need to make sure the spout connector is there and plugged in tight, and if it is you need to check the wiring. The PIP sensor in the distributor could be causing problems with the missed firing. It has a tooth for each cylinder, and if one tooth is messed up then it won't fire for that cylinder.

Now your code definitions aren't quite right, you need the actual F150 book to get the proper definitions.
173= HEGO shows system always rich. This will happen with one cylinder not firing.
213= Spout circuit open, I've explained this already.
411= Cannot control rpm during KOER low rpm check. With one cylinder misfiring the idle is unstable and the computer can't smooth it out.
538= Insufficient RPM change during KOER dynamic response test, operator error. You did something wrong pertaining to the wide open throttle test. Maybe you waited too long to nail the throttle, or you didn't floor it all the way, or something else.

gdowle

thanks mate,

do i need to remove the whole distributor or just the cap to see these teeth?

there is a spark but do you think its possible that its at the wrong time if the teeth or sensor are not right?

Just call me Sean

iTrader: (1)

I've never looked in there, but I think you can see the sensor just by removing the cap. Depending on how the sensor is damaged, if it's damaged, I suppose it could affect when it fires. I'm not sure if you're even having a problem with #2. The spout problem is enough to cause a pretty crappy running condition and the HEGO rich code. Work on getting the spout fixed first and see how it runs after that. Do you know what the spout is? I can post a picture if needed.

gdowle

yea its the little grey box near the icm. i had to disconnect it to check ignition timing. do you know if there is a way to test the spout? and what voltage should i be getting to the spout?

the reason why i thought its just no.2 is because if i disconnect each plug lead individually while running they all make it run worse apart from no.2.

if its just the spout after all this im going to kick myself.

Just call me Sean

iTrader: (1)

If you didn't erase computer codes after checking the timing then the spout code can still be stored from when you checked timing, so that may not even be an issue. The spout just completes the circuit from the computer to the ignition module. Removing it stops the signal from reaching the module. I don't know if the signal is positive or negative. Test the spout connector to make sure it isn't broken. Just remove it and check it for continuity. You can erase codes, run the engine and check for codes again to see if the code was from before.

From what you are saying it does sound like all your problems are from #2. Since you have changed around all components from #2 and are still having problems, I will have to say it's an electrical problem. You need to test for power and ground at the #2 injector plug. All the injectors have constant power, and the constant power is the red wire. They are fired by a pulsing ground signal. The ground wire is white for #2. Check for constant power and then check for the pulsing ground.

Good old Bill

Just to clarify what Sean said, so I understand better, power is applied to all injectors. They won't fire or open untill a gound is found. Thats the PCM or ECM. Have seen both terms used. Its the computor that grounds each injector (fire injector). Am I correct, if so why didn't you check that first? Don't mind me, I'm just a putts. I really think Sean has hit the mark.

gdowle

ok ill have to get the test light out. the led injector tester went into both terminals though