Hi I have a 98 ranger that up until the other day was running... Ironically I had gone to O'Reilly's to scan for codes ... It scanned just fine.. was reading many codes of which I identified the problem as being a blown fuse number 13 in engine compartment.. I thought problem solved. Well my old lady... ( It's actually her truck)... Had just come out of the store.. and she was feeling like it might have been a bad sensor... I tried to explain to her and the store employee that came with her that I believe I'd just found the issue.. they proceeded to look around the engine bay grabbing plugs and wires trying to identify sensors... Eventually employee went back in at a loss not finding what he was looking for... We went to leave and it just cranked and cranked... Would not start .. I was mad haha..hooked the scanner back up and what do you know ..now it would not read... The check engine light does not flash on when I turn the key on....not that I can remember if it did before... So I can't confirm or deny a blown bulb...but that was making me immediately suspect a ground issue somewhere and that the pcm Was not powering up ..Anyhow I have done quite a bit trying to get it to run since then with no luck. I can say that all fuses and relays appear to be good .. I cleaned up connections to the battery.. I've looked EVERYWHERE for and sign of a loose ANYthing. Pcm connector looks fine... No corrosion etc... I believe it to be a bad ground of some kind... I'm not great with a multimeter... And help would be greatly appreciated before I go throwing more parts and freezing my *** off trying to fix it... It's still in their parking lot... It's OUR ONLY VEHICLE.
edit 1- just remembered that I also made sure the fuel pump was turning on.. I could hear it. I also tried to check spark with what tools I had on hand... Pulled a plug wire and put a screw driver in and out the screwdriver next to the engine... Did not see any type of spark at all.. plz help

 

Welcome to the forum

Yes, the CEL should come on with key on, every time, that means the computer(PCM) has powered up
No Start is because No PCM, i.e. no CEL
And no OBD2 either

In the Engine Fuse Box
Check fuse 8, 30amp that powers the PCM via PCM relay

Check fuse 19, 25amp, in the Cab Fuse box, that turns on PCM relay with key on

 

The relay does click.. and I had already tried swapping it with the ac relay... As far as number 8 fuse.. I swapped it with one of the others as well.. I do not believe either is bad.

Are you referring to the big green Number 8?.... Because I thought that was a relay. Or the small maxi 8 marked in red? Either way I've tested and or swapped every possible relay and fuse

 

Also there are several fuses in the cab box that are good but still not getting power

 

The wind is raging right now and the truck is still at O'Reilly's... I live about 10 miles away. Or I would do more tests right now. I assume you are and active member Rond ? If so I hope that when I can get out to it. I can get more suggestions. I personally feel that this is a connection issue.. as it was fine till they went and touch and wiggled stuff looking for a sensor... but I can't rule out that the pcm may have died.

 

Sorry I think I may have replied wrong I added more posts to the thread instead of trying the quote

 

PCM didn't die, they don't do that, its just not getting power, or possibly no Ground but it has 5 ground points so unlikely
Not much in the engine bay wiring you can mess with to cause a No CEL/No Start, just in the engine bay Fuse box

This is pretty much all there is for the 12v power path for the PCM
Battery positive------fuse 8------PCM Relay-----------PCM


If engine turns over then Ignition switch has power, so its odd other systems/fuses have no power with key on
Focus on getting the CEL to come on

Not sure what else to tell you
The PCM relay also powers all the fuel injectors, IAC Valve and the EGR solenoid
IAC Valve is probably easiest to get to, will have 2 wire connector, the RED wire should have 12v with Key On if fuse 8 and PCM relay are working

Which Fuse 13 was bad and you replaced?
Engine bay fuse box
Cab fuse box

 

wasRhe engine

It was the engine bay fuse 13... I'm pretty sure I checked the iac and it did have 12v with key on.. still no cel no start.. since then I have gone through nearly every bit of wiring on it and can't find anything wrong . I'm about to get a ride to it to run some tests so I hope you are available

 

Disconnect either battery cable, wait 1min, then reconnect
Can't hurt, lol
Anytime there is an issue with something electronic...............Reboot

 

I Had tried that once before... Last night I pulled off the pcm Connector . I was able to verify 12v with key on at pin 26 which my diagram says is ignition. What should I test next?

 

26 is one of the coil packs, doesn't power PCM, gets 12v thru coil pack from fuse 19 in cab fuse box

Pin 71 is Key On power
Pin 97 as well

Pin 55 is full time 12v power but doesn't power up the PCM, just holds memory

 

Well then the diagram I looked at on Google must have been incorrect? Which is odd because the connector was identical to mine

 

well I have made some progress.. after checking pins you gave me.. I realized that it HAD to be a bad computer...my suspicion was made stronger by the obvious odor of fried electronics... Not only did it indeed die bro...it died in spectacular fashion...one of the chips on the board had exploded lol... I went to a junkyard and pulled another computer out of a 99. Although it had a 3.0 it looked identical..after swapping the computers... And attempting to fire.. she showed her first signs of life.. obd connector is working again.. and it does try to start if I use startkng fluid...it's starting extremely rough and backfiring.. since I can now rule a lot of things.. what I'd your suggestion on my next step? I don't believe the injectors are firing..maybe crank sensor too? I wish I had a noid light tester to see.

 

Glad you found the issue, would never have thought that

EEC-V Computers ALL look the same, you need one from a 1998-2000 Ranger 2.5l or Mazda B2500, also needs to have the same transmission, i.e. Manual or automatic

These will have correct firing order and injector pulses to run the 2.5l engine
Software is different and firmware(number of injectors and number of spark plugs) for different engine sizes, also automatic trans computers have added software for shifting, if used in a manual trans vehicle the CEL will come on and stay on because no automatic trans solenoids and sensors

 

Okay so imma need to return the one I've got then? ... And find the exact one. Makes sense.. yeah the one I've got is off the 3.0 oddly enough the cel still refuses to come on with the new one

 

Also the 2.5l Computers didn't have PATS(passive anti-theft system) like the 1999 and up V6 computers did
Ranger/Mazda 4cyl models didn't get that until the new 2.3l Duratec was used, starting in mid-2001

 

I have a 2.5l 5speed ranger cranked and drove fine as usual home a few weeks ago but in the morning it would turn over but never start tried the 50/50 test and still no start it's getting spark and has fuel pressure.. so I replaced the maf sensor still nothing so we put new crank and cam sensor in it still no start so we tore it down and timing seemed fine but went ahead with new belt and everything and made sure it was timed correctly put it back together and everything spins but still no start lastly we tried a pcm from another running truck and still no start and original pcm starts other truck I'm confused and at a lost...ANY HELP PLZ

 

Welcome to the forum

You should have started your own thread

No start on 50/50 test should have sent you to spark and compression, if you think there is spark then only compression is left

Get a compression gauge and test at least 2 cylinders, all 4 is better
160psi is expected

Gasoline engines need 3 things to run
spark, at the right time
fuel, mixed with air
Compression, above 100psi

Timing belt was a good call, but it relies on timing marks on the gears to be accurate, woodruff keys shear off................
Compression test tells you if crank/cam timing is OK

Crank sensor sets spark timing........base on the Tone ring(reluctor wheel) on the back side of crank pulley, seen here: https://i.ebayimg.com/images/g/s4sAA...yhg/s-l400.jpg

That tone ring is "press fit" nothing to hold it in place except friction, no "key", just press it on and pray, lol
These very very rarely shift positions, so a long shot
In the picture you can see the #1 TDC "missing tooth", its about 4 teeth away from cranks woodruff key slot, if you can see key
If you have, or can get, an old time timing light you can check if #1 is sparking at TDC when cranking

 

Ngl I could not for the life of me figure out where to go to start a new thread so I just found one as close as I could...and thanks so much for the information I actually have compression tested 3 of the cylinders and they were all reading roughly 145-150 with almost 300k miles on it in my opinion that's acceptable but I will definitely look into if that tone ring has shifted and on the crank

 

Just for future reference, from Main page select any sub-forum, in this case "General Ford Ranger Discussion" and you will go to this page: https://www.ranger-forums.com/genera...discussion-15/
Left side, upper/center, just above the "stickys"
"+ New Thread", click on that

145-150psi is fine
Should start using 50/50 test if there is spark, at the right time
Repeat 50/50 test any time you make a change, its by far the best test for "crank, no start" gasoline engines, first used in 1890's with first gasoline engine, lol

Also watch the CEL, it should come on with key on, and then it should go off when cranking engine over

Extreme longshot, but has happened
A fellow had his gasoline siphoned out and replaced with water, why?.........who knows
But engine wouldn't start of course and even with 50/50 test because the water was being added to cylinders from the injectors while cranking
Simple test was to crank engine over a few times
Pull out a WET tip spark plug and light the tip with a match, gasoline should burn easily and quickly, his didn't, so not "a fuel"
He drained his tank and added fresh fuel, and was back on the road