The Brain

[Dav]

first, the history.
95 2.3 auto gave a bang and several jerks before settling down to run from the traffic light. 30 minutes later it died and would not restart. as soon as AAA unhooked it, it started right up but ran ragged. dog up to high rpm's, then a race horse.
thought it jumped timing but found it had sheared the crank pulley keyway.
U-pick supplied a pulley and Ford had the keyway (only $2.46!) so it's back on the road. but it still runs ragged.
the Question,
should i reset the computer and if so how do i do it? i think (and this might show my computer ignorance) that the computer remembers how you drive and adjusts accordingly. since it ran for 2 weeks at a BTC state, it might think it is still in one.

 

[Mark_88]

I don't think resetting the computer is actually possible other than just disconnecting the battery and leaving it to dissipate the capacitance charge...if that is even applicable.

Sounds more like the timing is still out a tooth or you may have plugged fuel lines, a bad spark plug, or possible plugged cat.

the BANG may have caused something in the cat to break loose and plug up the screens that do the converting of the excess fuel so I would suggest maybe check plugs, check fuel pressure and flow and see if there is anything coming out of the tailpipe.

A strong running engine with a free flowing exhaust will have some pressure coming out...if it is plugged that might not be evident.

If you want to try the resetting first then it won't actually hurt anything...might even help...but I've never seen that actually do anything...maybe someone else has and hopefully they will contribute.

 

[Dav]

okay, disconnecting the battery is easy enough. how long should it take to discharge the capacitor? (i'm on my 3rd beer so the truck is going NOWHERE until morning)
i rechecked the timing- spot on
just held my hand over the tail pipe[ there is flow that seems adequate but it reeks of gas. can i just remove the cat and put in a straight pipe (i'm not in california) or will that raise hell with the brain?

 

[Mark_88]

If you are smelling gas I would suggest checking for codes. If the CEL is not lit on the dash then you may not get anything as far as codes go but worth a shot.

Exhaust should smell like exhaust which I'm sure you know how that smells...and it does not usually smell of gas at all...unless it is not burning properly...which could be a broken plug.

The battery should be left unlplugged for at least 20 minutes but give it 30 in case I'm wrong. That won't get rid of the gas smell though so i would suggest pulling the passenger side plugs and see if there is any damage or problems with the gap.

You are running 8 plugs and, hypothetically, the waste spark system should detonate all and any gas that the passenger side does not ignite...maybe a coil problem or simply not firing on one cylinder at all...but that would mean both coils are pooched and that is not likely.

If you don't have a code reader you can get the codes from some auto parts places for free...maybe call around to check if you need to.

 

[Dav]

disconnected the battery ground last night. put it back this am. no improvement. runs ruff like timing is still advanced.
dug out a timing light and checked all 8 wires. getting spark at each but front coil seems to miss more often than back one i have a spare coil so i will give it a try
just went to the parts store. their code reader shows nothing. truck did start right up as i was leaving parts store. hope computer has reset itself but i'll swap the coil anyway

 

[Mark_88]

I would hazard a guess that the voltage specs would increase or decrease from 5 volts to indicate engine temperature but RonD probably knows for sure what they should be. He hasn't been around much in the last few months but is still posting. I was collecting and saving some of his posts for reference material to teach myself more about Fuel Injection but not sure if I have something on temp sensor specs.

I thought I had a link to a troubleshooting site but it seems to have moved or shut down. One of our members, Angie, provided the following link that might help you find what you want for the temp sensor specs.

http://workshop-manuals.com/ford/

We also have the on-line manual at the following location (use the user name and password in the link if it doesn't pop in when you click it) and you just select the year, make model.

http://www.therangerstation.com/forums/showthread.php?t=170166

I will check my RonD notes to see if I saved anything about the temp sensor...I know it affects idle and operations on later models but not sure about pre 1995 as to when the computer took over the control of engine functions from the ignition control module.

 

[Mark_88]

I didn't find anything on the temp sensor but I did remember the Fuel Pressure Regulator may be leaking fuel...you can test that by pulling the vacuum hose off and sniffing it...if you smell fuel in the hose that indicates that the FPR is leaking fuel directly into the intake so you will have way too much fuel dumping into the mix.

The FPR is on the fuel rail by the intake manifold. It is a round shaped object with a vacuum line running from the center of the intake manifold and it is sitting on the fuel rail by the driver side plugs.

I also realized that you are driving a 95 so my reference above to pre95 is incorrect.

 

[Dav]

your mention of the temp sensor got me to thinking. i disconnected it to pull the upper radiator hose free. i checked and i had put it on and it is tight. but i saw the hose from the vacuum canister just lying below the battery shelf. i slid it back on and what a difference!
tomorrow i will do the test drive to see what other problems there are.
thanks

 

[Mark_88]

Well, of course a vacuum leak will also cause it to run like crap...lol

I hope it is as simple as that...more often than not it usually is an oversight and I know I've caused myself more problems by knocking things off than I can count...