I need help, please and thanks! 1990 Ranger 2.9L

[Spadilla7]

Thanks, Franklin. The R/LB wire goes to the starting system, and this is where I think the problem may lie. The R/LB wire connects to the white pink which connects somehow to the neutral switch. I have no power at the r/bl wire when trying to start. I just cant seem to locate where the white pink splices into the R/LB wire complete the circuit, if that is the correct terminology.

PS- I do have power to the coil and also to the r/gn wire.

 

[franklin2]

Does the engine crank over? You should have a red/lightbue over at the starter solenoid, that is what triggers it to send power to the starter. You can see in the diagram below the pink wire is way up the line, the tap off for the ignition is down lower on the red/ightblue.

 

[Spadilla7]

Here is the diagram I have been using. If you look at the nsf you will see the the white/pink wire I am referring too. None of the other diagrams even show the white pink wire.

 

[Spadilla7]

Franklin, to answer your question about the crank, yes the motor turns over, but it will not start. I am frustrated by the wiring diagrams because I do ALSO have that solid pink wire shown in the other diagrams. Its like a have a homologation harness from multiple years. IDK, frustrating, to say the least.

 

[franklin2]

See in the diagram above you posted? If the white pink wire was disconnected, the truck would not crank over. You said you had the wiring uncovered. Can you find the red/lightblue at the TFI connector and trace it back? Or easier would be to get a testlight or voltmeter and put it on the wire at the TFI connector while someone cranked the engine. If it has power, you can go and look for the problem somewhere else. I would try to leave the TFI plugged in when check for voltage on the wiring.

 

[Spadilla7]

I have traced the r/bl from the TFI harness through to the starter solenoid, nothing to see there. I have power to the starter, the starter works, engine cranks, power at the r/bl on the solenoid, but no power at the r/bl wire at the TFI when trying to crank. I honestly think that this white/ pink is not completing the connection to send power to the start pin on TFI via the r/bl wire. The truck ran before the head replacement. Everything is back together, except this one wire, and I don't have a spark. I just don't have any other explanation or place to look other than this wire connection, or lack thereof.

The lead of the white/pink wire is about 12-18 inches in length, wherever the white/ pink wire connects must be on the driver's side somewhere, but the options are limited as to where it could be. I have opened up the harness along the firewall, nothing there. If I knew where the vicinity of where S121 from the diagram is located, then I could trace from there to see if I can find the break.

 

[rumblecloud]

Peanut gallery question:
@franklin2: In your last post, are you essentially asking if there is any juice flowing through the Pink/white wire? Because that's what I was kinda wondering.

 

[franklin2]

Peanut gallery question:
@franklin2: In your last post, are you essentially asking if there is any juice flowing through the Pink/white wire? Because that's what I was kinda wondering.

He is stuck on this loose wire that he doesn't know where it goes. It may well be the problem, but when you don't know where it goes and no one else knows what wire it is, then that is a dead end and you have to re-group.

That is why I am trying to presuade him to forget about the wire for now, and do some generic troubleshooting with a meter. He said in his last post that he traced the red/blue from the TFI all the way back to the starter relay, and the engine cranks over. So that means the red/blue is getting power. And the red/blue is connected to the TFI. But he can't get power at the red/blue TFI connection. I would try to figure this out. And also make sure I had power on the red/lightgreen that feeds the TFI and the coil.

 

[rumblecloud]

Got it! Thanks for taking the time to reply.

I'm not nearly as knowledgeable as you are, but sometimes we fixate on one ting so much that we overlook the simple things -- which is I think where you are headed. This is a learning string for me and I am curious to see it play out.

To me, It seems like if you have power/spark to the coil and then no power/spark to the plug(s), then the problem would lie in that area between the coil and the plugs -- again, I'm not that smart.

Thank you again.
R

 

[Spadilla7]

I do have power from the r/gn to the coil. I have power on the r/bl from the solenoid when trying to crank. But I have no power at the r/bl at the TFI. This pink white wire ties into the r/bl somewhere, if I find where it connects that probably will fix the issue the r/bl could be broken or this white pink is supposed to connect to it. The r/bl starter lead to the TFI is broken somewhere, combine that with this mystery wire and I feel that is my issue. I have checked and replaced everything electronically thus far. Coil is new, checks out spec wise with voltage and resistance. New cap and rotor, brand new dizzy and not a reman, new wires, plugs gapped to .044, new ignition switch, new ignition cylinder, compression is good on all cylinders, new solenoid, starter is good, fuel pumps works, I have about 42psi at the rail, vac lines are new and hooked up, no leaks. What I am left with is that I have a single wire that is broken, and that ties into the TFI somewhere. I mean what else could it possibly be? Everything else has been eliminated except the ecu and I have gotten codes from that so I feel it is working properly. The Ecu doesn’t do anything with the start up anyway. I am literally at a loss.

 

[Spadilla7]

Got it! Thanks for taking the time to reply.

I'm not nearly as knowledgeable as you are, but sometimes we fixate on one ting so much that we overlook the simple things -- which is I think where you are headed. This is a learning string for me and I am curious to see it play out.

To me, It seems like if you have power/spark to the coil and then no power/spark to the plug(s), then the problem would lie in that area between the coil and the plugs -- again, I'm not that smart.

Thank you again.
R

What is between the coil and plugs is the distributor, TFI, cap and rotor. There is a start wire on the TFI that is r/bl it should be hot when attempting the start the truck. There is no power there. There is a red green to the coil, from the ignition, and I have the proper voltage there when switched on. If the TFI isn’t getting all the signals, then the truck simply won’t start. There lies my problem.

 

[franklin2]

I do have power from the r/gn to the coil. I have power on the r/bl from the solenoid when trying to crank. But I have no power at the r/bl at the TFI. This pink white wire ties into the r/bl somewhere, if I find where it connects that probably will fix the issue the r/bl could be broken or this white pink is supposed to connect to it. The r/bl starter lead to the TFI is broken somewhere, combine that with this mystery wire and I feel that is my issue. I have checked and replaced everything electronically thus far. Coil is new, checks out spec wise with voltage and resistance. New cap and rotor, brand new dizzy and not a reman, new wires, plugs gapped to .044, new ignition switch, new ignition cylinder, compression is good on all cylinders, new solenoid, starter is good, fuel pumps works, I have about 42psi at the rail, vac lines are new and hooked up, no leaks. What I am left with is that I have a single wire that is broken, and that ties into the TFI somewhere. I mean what else could it possibly be? Everything else has been eliminated except the ecu and I have gotten codes from that so I feel it is working properly. The Ecu doesn’t do anything with the start up anyway. I am literally at a loss.

Just for an experiment, why don't you take a scrap piece of wire, tie it to the red/lightblue on the solenoid, and then run it over and temporarily hook it to the red/lightbue at the TFI and see if it will run. Then at least you will know you are on the right track if it runs.

 

[gaz]

Spadilla7,

I agree with Franklin, except I would start with the primary power relay under the hood. Follow that power to your coil, distributor (ignition module) until you locate the missing signal.

Do you understand how a basic 5 terminal relay works ..). This is exactly how I found the where my "START" signal was lost/stopped.

Be patient and keep sharing on here, sometimes just reading my own words helps me figure problems out.

 

[Nez'sRanger]

At this point, I think it would help to do a detailed investigation of the wiring. I had an issue a while back after lifting the engine out to change the oil pump. When I put it back in, it ran like crap. Took me weeks of troubleshooting and chasing symptoms. Ultimately, I figured I butchered a wire somewhere while lifting it out. Went to the junkyard, bought an old engine harness, took it apart and hand inspected every wire and every connector, soldered and spliced where necessary, rewrapped it, and installed it. Problem solved.
With these 30 year old trucks, sometimes just moving stuff around is enough for the plastic wire insulation to crumble off and cross wires.
Just a thought, but hey! At this point, you're almost at wit's end like I was, haha!

 

[4x4junkie]

I have a 1990 FSM wiring diagram book...
That white/pink wire you showed earlier appears to go to the oil level sending unit (located on LH (driver) side of oil pan) (circuit #258). I don't think it has anything to do with your issue.
Tracing it backward, it just goes to a relay to light the "Check Oil" lamp on the dash.


Tracing the red/lt. blue wire (circuit #32) backward from the TFI module, it goes to an 8-pin round connector at L.H. fender (plastic inner fender). From there it goes to the Park/Neutral safety switch on LH side of trans (assuming the auto trans your profile states) where #32 connects to circuit #329 (pink) only while in Park or Neutral. From there, circuit #463 (red/white) splits off of #329 at the safety switch and goes to the 4WD electric shift module (disregard if 2WD or manual 4WD), while #329 (pink) continues to the giant round instrument panel connector (pin #30) to the 6-pin rectangular clutch safety switch connector under the dash (which should have a jumper plug in it). From there, #329A (pink) runs to the ignition switch, and connects to circuit #37 (#10 yellow wire) during Start only. The #10 yellow wire runs to the Power Distribution (fuse) box under the hood to fuse #10 (60 amp). From there it goes to the battery positive terminal.

I suspect somewhere along the above route lies your issue.