hello everyone im new to the forum and looking for some help. ill start from the beginning.

first off im driving a 92 f250 351w.about 90k on motor. 200+ on truck.

pulled truck over to garage on sunday to clean all the kids stuff outta it. it had a dead battery so i jumped it with the sho and after a few cranks started up. after about half hour of cleaning went to start truck again and crank but no start. originally i thought no fuel because of close to empty tanks and incline i was on. 5 gallons of gas through that out the window.

next went to spark. and of course there is none. i checked spark using a spark tester from plug wire to plug and also coil to cap. nada. replaced coil, icm (it was bad, known by autozone test), distributer, cap, rotor with known working parts from garage. still nada.

also made sure battery was fully charged and checked inertia switch.

also figured maybe a code check would prove something usefull. now hers the part that really stumps me. no codes. i tried checking codes using 2 methods. first paper clip jumper method (have done this many times before on my sho and ranger) the CEL doesnt even light up. second i decided id purchase a code reader incase i did something wrong, for 30 bucks i figured what the heck, at least i wont need the paper clip no more. when hooking it all up with key off the light and audio came on on the reader. so i turn key and boom reader goes off. i mean turns off. no light no sound nothing. i tried this 3 times to be sure and everytime same result. whats the definition of insanity? trying the same thing over and over again expecting different results. so before i go insane with this id figured id better get some help. thanks in advanvce for all help given.

matt

 

Do you have power to the injectors?
Do you have power through the ECU relay? (relay that powers the computer)
Check for good ground connections, ECU, engine etc.

 

i remember seeing a post when searching about how to check injectors but ill be darned if i remember the name if you could give me a how-to or point me in the posted direction ill check that out. also i havnt been able to find a schematic to tell me which relay goes to the ecu. id actually like to have a schematic for the whole fuse box under the hood.

there are 2 sets of relays under the hood. 4 in the fuse box and 2 in a box next to the fuse box. that box reads backup relay and charging system relay.

i did go over grounds and they all seem to be fine. i will go over them again just to be sure.

also im not sure if i mentioned this before but the CEL doesnt even come on when i turn the key to run. it doesnt even light up anymore. not sure if this helps. thanks for the reply. ill run a few more tests and get back to yall with anything i come up with.
matt

 

wiring diagram for 92 f150 5.8
http://www.autozone.com/servlet/UiBr.../3a/41/0900823

what to look for when you can't get codes
http://fordfuelinjection.com/index.php?p=44

The ECU should be under the dash on the drivers side, and the relay should be next to it.

 

It looks like the link in my last post for the the wiring diagram is'nt working for some reason. If you go to www.autozone.com enter your vehicle info, click on repair info, the wiring diagram can be found under chasis electrical. It will show you several diagrams, just look for your year, model and engine size.

 

went through the no codes section and didnt come up with anything. all grounds are good cleaned and reattached. all connectors and fusable links seem to be ok. fuses and diode are in working order. pin 30 senses ground. no after market parts. nothing visualls wrong with pins, no corrosion and no noticable loose wires. pin 48 grounds. pin resistance between 20, 40, 60 is all about .035. pins 1, 37, 57 all read out to 12.5.

still need to check pins 26 and 46 when attached.
when measuring resistance between 46, 40, 60 does computer need to still be attached?
my ecu is located on firewall under master cylinder. there is no relay near it that i can see. only relays i see are the 4 in the fuse box and the 2 in the box next to fuse box (they read backup and charging). and they are all little black boxes about 1"x1". are these the correct relays?
also did not get to CEL light yet will later when have more time. but i assume it is good since it worked prior to the problem, but will check anyway.
i did switch the relays around to see if it made any change but none.

i also checked the voltage at the coil wires and did the light test. have full light on + side, full light on - side. when cranking the light does not flash when connected to - side. the light dims from the cranking but not flashes. i did the same test on my ranger so i knew the difference between the flash and the dim. also disconnected the spout. now just to be sure the spout is the dizzy correct. i disconnected the wire harness from the dizzy. is this correct or is there something else i was sposed to disconnect? i also hear the FP when the key is turned on.
there was no schematics on autozones website for this truck that i could find. everytime i put year and make it kept going back to year. i do have the chiltons book and they have a chasis electrical there but nothing for the fuse box itself.

 

What about the pickup assembly in the distributor? Unfortunately, distributor has to be removed, then pins, gear and shaft.

 

i replaced the whole dis already including cap and rotor with a working spare i had in garage.

 

The wiring diagram I was looking at for the 92 did'nt specify where the ECU relay was for the 92, I was judging by the later models and mustangs. If your getting power in on pin 37, that's where the ECU relay feeds into the computer, so the relay is probably ok, and the ECU should be getting power. If you need to find it, it has 4 wires, red, yellow, black, and black w/ yellow stripe. Disconnecting the spout does not involve disconnecting the distributor harness. Leave that pluged in. Disconnecting the spout, takes out the advance that the ECU is controlling allowing you to see the initial advance or where the distributor is physically set. According to the manual I have here, the spout connector on your 92 should be near the self test connector on the drivers side inner fender. Should have 2 pink wires. Just pull that little plug to disconnect it, whenever you need to check/set the timming. Be careful where you use the test light and volt meter. Most of the sensor circuits that use a 5 volt ref signal can be damaged if you don't use a high impedence volt meter. Have you checked the neutral safety switch? Wiggle the shift lever from park to neutral (automatic) or check the neutral switch on the clutch. (man trans) I always like to check the simple cheap stuff 1st.

 

ill check on that later on today or tomorrow have a lot of running around to do today, mothers day and all. thanks alot for the help and redirecting me to the spout. ill post as soon as i have more information.
thanks again,
matt

 

ok took me a few days longer than expected but im back. let me make sure that i have done this correctly. the spout is just a 2 wires running into a little gray box kinda like a relay or fuse or something correct. if that is correct i took out the little box and tried the light on the coil trick again. full power to the pos sisde and now blinking when i crank from neg side. pulled the ecu and as soon as i got it out i could smell it had been burned. opened it up and sure enough it was. ill have the new ecu tomorrow so ill let yall know what happens after i put her back together.

 

You mentioned earlier that you jump started the truck prior to having the problem. I have heard that jump starting could create problems with computerized vehicles, due to voltage spikes etc. May be a good idea to disconnect the battery and charge it or replace it with a good one vs jump starting in the future. It may be more of a hassle, but I consider it cheap insurance.

 

well i put new computer in and she fired right up, so ill go with that being the problem. hoping that it was just age or the jump that fried it but nonetheless it is running gonna do timing later today and shell be good to go. thanks alot for the help jade and pointing me in the right directions.
matt