Dead Cobra on the side of the road….

[THayes]

I would appreciate any thoughts, suggestions or insight to an intermittent electrical problem I'm having on a Ford 302 using the Ron Francis wiring sold by Factory Five. Car ran approximately 1200 miles with no issues…a lot of fun to drive. Then started just dying on the road, anytime anywhere. A little embarrassing having such a nice car dead on the side of the road. I've traced out the grounds, checked and or replaced distributor, coil and engine control computer and nothing comes up on reading the codes. The car just dies and takes the fun out of even driving it. It's not temperature related, it's happened on a cold start and died. Sometimes it starts back up soon after and I can get home…other times it's a long time before it starts back up again. There is nothing getting to the plugs…no spark. I just don't trust driving it anymore…and it's too fun of a car to just sit in a garage. Any help would be suggestion or troubleshooting guidance would be appreciated.

Thanks…

Tom

[DaleG]

Simple stuff first: probably wires to the starter switch. Happened to me.

[2FAST4U]

Tom
Are you running an MSD box? They've been known to fail

[THayes]

Thanks for the replies…no MSD box, pretty much a stock 302 and parts running bored .30 over. Nothing exotic. Car cranks fine, distributor turning…just no spark. Sometimes a minute, sometimes an hour later it starts back up. I thought it could be temperature related, but it's happened on a cold start. So I'm at a lose….

[2FAST4U]

Sounds like a bad coil

[THayes]

Thanks Dale, The car cranks over fine…..wires to the starter cause a lose of spark?

[2FAST4U]

Thanks Dale, The car cranks over fine…..wires to the starter cause a lose of spark?

No. Losing power sounds like a bad coil

[michael everson]

Did you actually replace the distributor? If not, replace it. There is a unit in there that is known to fail. I cannot remember what its called right now. I had this very same thing happen to a customers car. His donor was a 1994 Also you might consider a new TFI module as well. Find a known good distributer and bring the proper tools with you on your next drive. When it dies, swap it out and see what happens. Thats how I fixed it.
Mike

[DaleG]

Thanks Dale, The car cranks over fine…..wires to the starter cause a lose of spark?

Mine would just cut off while driving; no power at all, wouldn't crank. Sometime later, it would start. Found out it was the ignition switch by reaching under the dash and fiddling with the wires. Doesn't sound like your problem.

[Mike N]

Start off with the simple stuff first. Get a test light (probe) if you don't have one. Next time it dies check voltage to the coil, check voltage to the distributor. If both are good then start looking deeper into the coil and distributor. If you are not getting voltage then start tracing things back until you do. I have had similar issues in the past and it has been loose, badly made or corroded connections, and in one instance it was the ignition switch (key). If your have the Ford EEC set up with the TFI distributor it may be related to the pick up of TFI module although usually they only act up when hot and not on cold start. Coils are similar although if there is an internal intermittent connection then it could be the coil.

Are you sure it's ignition related? I had a fuel pump ground that was a little flaky a few years back and that acted in a similar fashion. I ran a ground wire from the tank to the frame and that fixed it.

[THayes]

Start off with the simple stuff first. Get a test light (probe) if you don't have one. Next time it dies check voltage to the coil, check voltage to the distributor. If both are good then start looking deeper into the coil and distributor. If you are not getting voltage then start tracing things back until you do. I have had similar issues in the past and it has been loose, badly made or corroded connections, and in one instance it was the ignition switch (key). If your have the Ford EEC set up with the TFI distributor it may be related to the pick up of TFI module although usually they only act up when hot and not on cold start. Coils are similar although if there is an internal intermittent connection then it could be the coil.

Are you sure it's ignition related? I had a fuel pump ground that was a little flaky a few years back and that acted in a similar fashion. I ran a ground wire from the tank to the frame and that fixed it.

Thanks Mike. I have replaced the coil just on principle and the distributor replaced early on. I carry an extra TFI module and changed it out at the last fail with no changes. The spark plugs don't fire at all when the car dies and I can hear the fuel pumps going and have checked the pressure, it seemed the fuel wasn't the issue. Just no spark. I'll have to setup a few test lights next time out and see if I can find the point of failure. Everything is fairly new and with the new Wiring Harness from FF, I thought I wouldn't have any problems. The car ran fine for the first 1200 miles. Frustrating!! Thanks for your input…..

[michael everson]

Whos engine harness is it? Stock or aftermarket? If the coil, distributer and TFI all check out, I would next look at the computer relay. If its stock mustang, it should be right near the computer.
Mike

[THayes]

Thanks Michael, I haven't looked at those relays as yet. It's a Ron Francis wiring bought from Factory Five, so not the stock wiring. I was hoping to avoid problems like this using a new wiring harness over the donor harness. I'll check those relays. Thanks for the input….

[skullandbones]

Hi Tom,

I don't have first hand experience with the RF harness but it sounds similar to my AAW harness from everything I have read. I was wondering if you have any inline circuit breaker in your system like to the computer. This would explain the shutdown. The overloaded circuit could cause the breaker to open. When the circuit breaker resets it restores current. I believe I have one on each of my fan circuits going to the relays. Sorry you're having to chase this gremlin. It is frustrating to have a tricky electrical problem. Good luck, WEK.

Note: Also, if you did all the wiring on your project, go back to the wiring diagrams and your notes on the different wiring tasks and retrace the circuits. Sometimes it will give you an idea of a possible culprit.

[CraigS]

My MkI w/ stock 302 efi and donor harness had a fuel pump relay problem. It acted more like the ignition was cutting off than it was running out of fuel. But a smack on the pump relay would get it going again. Replaced the relay and problem went away. I don't know if that pump does more than just run the pump or if it also sends a signal to the ecu but something was happening that gave symptoms not at all like the pump was shutting off.

[THayes]

Hi Tom,

I don't have first hand experience with the RF harness but it sounds similar to my AAW harness from everything I have read. I was wondering if you have any inline circuit breaker in your system like to the computer. This would explain the shutdown. The overloaded circuit could cause the breaker to open. When the circuit breaker resets it restores current. I believe I have one on each of my fan circuits going to the relays. Sorry you're having to chase this gremlin. It is frustrating to have a tricky electrical problem. Good luck, WEK.

Note: Also, if you did all the wiring on your project, go back to the wiring diagrams and your notes on the different wiring tasks and retrace the circuits. Sometimes it will give you an idea of a possible culprit.

Thanks for the input. It will be helpful with the troubleshooting. I have rung out some of the wiring that I thought might be the cause, but nothing definitive as yet. There is no circuit breaker in the harness or wiring, some fuses, but no breaker. I have a list of things to check from suggestions out here, just tough to find that intermittent problem. Thanks for the help.

[Doutie]

I had a similar problem and It turned out to be the MSD ignition box. I know you have already said you're not running one but while diagnosing mine I found very helpful information on the web. There's a site for Ford Broncos or maybe it was Rangers that had a very good, easy to follow test method for factory TFI. I think I just Googled 5 Liter Ford TFI Ignition to find it. Good luck

[tirod]

Conditions: nearly stock EFI with factory ignition. No codes. Dies, no fire, various time intervals, no temp relation.

The cause is an intermittent short or open. It's interrupting the computer's ability to calculate the firing order or injection. It's not going to be found except by a detailed electrical inspection when the problem exists, by a good auto electrical troubleshooter who can dedicate the time to find it with the car in hand. Just the same as a daily driver.

It's very likely something very simple, like the pickup coil in the distributor. Randomly testing parts won't catch it, it's testing it when it's NOT working that finds it. And it may not be anything to do with whatever chassis wiring harness is being used - it's much more likely the used EFI harness from the donor.

"Checked and or replaced" doesn't adequately describe or diagnose, no codes obviously means nothing. There is still a problem and things need to be checked, again, not given a pass.

I know it sound strict or like I'm a bit put off, but I'm like a lot of others - I got into it early in life because of the fun I had bolting together parts in new ways. Not messing with electrical stuff. But over the last 30 years, it's been the electrical stuff 90% of the time causing the real issues. A blown motor or transmission is really simple grunt work, been there done that over the last 90 days. Diagnosing a cracked trans solenoid that put the car in limp mode was something else. I took much longer to figure out compared to seeing shiny flakes in the oil and hearing a dinner bell clanging around inside a big aluminum casting. Those were easy. Flashing lights and no idea how the electrical wiring controls a 4EAT, not so much.

It's most likely an open either in a sensor or the wiring to the ECU. Once that happens, the computer shuts down as it can't calculate timing for the ignition or injection. If it can't be found, as said, start with the cheapest likely parts and work up to the ECU.

And by all means explain how the engine and chassis is grounded - that is a critical part of the electrical circuit easily overlooked.

[ehansen007]

Hey THayes. Have you thought about Vapor lock? I had this happen in the Hot Rod. On warmer days and track days the car would be fine then start to slowly run out of fuel and just die. Then if I waited for a while, it would start right back up and drive around fine. When I felt the pump it was hot. Just a thought.

[Bren]

Hey THayes. Have you thought about Vapor lock? I had this happen in the Hot Rod. On warmer days and track days the car would be fine then start to slowly run out of fuel and just die. Then if I waited for a while, it would start right back up and drive around fine. When I felt the pump it was hot. Just a thought.

What's the trick to running gas lines to avoid vapor lock?

[jimgood]

Tom, maybe this will have some useful info: http://easyautodiagnostics.com/index_ford_4.9L_5.0L_5.8L/index_of_articles_1.php

Actually, here's a link that on that sight that might be even more specific: http://troubleshootmyvehicle.com/ford/4.9L-5.0L-5.8L/how-to-troubleshoot-a-no-start-1

[seagull81]

Jim those are great sites, thanks.

[jimgood]

Jim those are great sites, thanks.
I lucked up on that. I like that it has actual diagnostic procedures for novices rather than throwing parts at the problem.

[SCFFR]

Just a thought along the vapor lock line. I had the same issue with an old Mustang. Would run great and then just die. If I waited a while, could crank back up and run fine.
In my case, fuel like ran to close to exhaust which boiled the gas in the line creating vapor.
I was told that the fuel pump should never pull fuel through a filter since this will cause air to form but should always push fuel through the filter. In my case was not an issue but something worth looking at.
On my MkIV, I covered my fuel line where it runs into the engine compartment with a heat shield. Can't recall the brand but it was a one piece that looked like a fuel hose. It wasn't split so had to be slipped over the line before connecting it to the fuel pump.

Hopefully you can get this resolved......I know it has to be frustrating.

Ron

[CraigS]

I like this stuff for hose insulation. It's split and held together by velcro so can be installed anywhere.
http://www.summitracing.com/parts/the-14035/overview/

[tirod]

An EFI system with 40psi in the feed line is much less likely to suffer vapor lock. The old carb systems were literally a siphon feed from the engine all the way back to the tank - which meant it was working under a vacuum to pull fuel forward. EFI, nope, a pump is pushing it all the way.

Nothing wrong with insulating the fuel lines, but as the OP stated, this was happening even with a cold start.

[dforthof]

Holy Cow!- Some great feeedback from everyone on this one. This is why I love this forum. A little tip from an old mechanic (now an engineer) - I would try starting the car and letting it idle, then going around and "wiggling" all the wire harnesses, give them nice sharp jolts like what they would expierance while the car was driving down the road. It's a nice quick test that may tell you something...

[michael everson]

Did you guys read the part about no spark? He doesn't seem to have a fuel issue.

Theres not many things that affect spark

Heres a partial list.

Distributor
Coil
coil wire
Cap and rotor.
ECM
Possibly ignition switch, but if the fuel pump comes on, this is unlikely.
Computers relay.

I know you said your replaced the distributor, but was it new or used? Rebuilt is fine too.

Wish you were near me. We could have this fixed in a matter of minutes once the problem presented itself.
Mike

[SCFFR]

One more thought. Could it be the dash mounted cut off switch that cuts power if the car flips over. It's part of the RF harness and is to be mounted on the dash support tube near the steering column. It interrupts power to the engine. Might explain why there is not spark at all. Maybe the switch is defective.

Ron

[michael everson]

Ron. That's a fuel cutoff switch. It activates in a rear collision.
Mike

[alpine227]

I would appreciate any thoughts, suggestions or insight to an intermittent electrical problem I'm having on a Ford 302 using the Ron Francis wiring sold by Factory Five. Car ran approximately 1200 miles with no issues…a lot of fun to drive. Then started just dying on the road, anytime anywhere. A little embarrassing having such a nice car dead on the side of the road. I've traced out the grounds, checked and or replaced distributor, coil and engine control computer and nothing comes up on reading the codes. The car just dies and takes the fun out of even driving it. It's not temperature related, it's happened on a cold start and died. Sometimes it starts back up soon after and I can get home…other times it's a long time before it starts back up again. There is nothing getting to the plugs…no spark. I just don't trust driving it anymore…and it's too fun of a car to just sit in a garage. Any help would be suggestion or troubleshooting guidance would be appreciated.

Thanks…

Tom

Two things to check, do you get a tach signal on cranking when it dies, and check for power at coil and TFI module when it dies. Maybe a bad relay for the ignition system. With TFI you can unplug Spout on the TFI and still run the engine.

V/R
John

[Atcogas]

I would appreciate any thoughts, suggestions or insight to an intermittent electrical problem I'm having on a Ford 302 using the Ron Francis wiring sold by Factory Five. Car ran approximately 1200 miles with no issues…a lot of fun to drive. Then started just dying on the road, anytime anywhere. A little embarrassing having such a nice car dead on the side of the road. I've traced out the grounds, checked and or replaced distributor, coil and engine control computer and nothing comes up on reading the codes. The car just dies and takes the fun out of even driving it. It's not temperature related, it's happened on a cold start and died. Sometimes it starts back up soon after and I can get home…other times it's a long time before it starts back up again. There is nothing getting to the plugs…no spark. I just don't trust driving it anymore…and it's too fun of a car to just sit in a garage. Any help would be suggestion or troubleshooting guidance would be appreciated.

Thanks…

Tom

I had the exact symptoms u have last summer. I found a bad fuseable link near starter solenoid. just got lucky testing while moving wires. I know the frustration. one minute all is good then nothing.

[Norm B]

I agree with Alpine227. Check for power at the coil when you're not getting spark. If you have power then the problem is in the ignition system (coil, distributor or computer). If no power at coil then you have an intermittent electrical fault (the best kind:mad:). Make up a lead with 2 alligator clips and hook the positive post on the coil to a 12 volt supply. See if you have spark. As for seeing a tach signal during cranking this may or may not indicate where the problem is. Some tachs are isolated during start for surge protection. I have a remote tach that connects directly to the coil for tuning and trouble shooting. See if some one in your area has one.

Good Luck
Norm

[Norm B]

Just had another idea. Check your engine ground.

Good Luck
Norm

[SCFFR]

Thanks Mike................for some reason my brain was thinking the clutch safety switch but my fingers were typing about the inertia switch. Now that I think about it, I guess mine doesn't do much good since I have a mechanical fuel pump.

Ron

[SCFFR]

Thanks Mike................for some reason my brain was thinking the clutch safety switch but my fingers were typing about the inertia switch. Now that I think about it, I guess mine doesn't do much good since I have a mechanical fuel pump.

Ron

[JJ'snakepit]

When you do find it be sure and post your solution so we can all learn... Thanks JJ

[skullandbones]

After all the input you've gotten and still no headway (even changing out the PCM), I would suggest as others have to take it to an electrical expert. They can probably isolate the issue that you may never find without the necessary equipment. We don't always get the resolution to these problems as it may be embarrassing to some to share the particulars but I hope you will keep us posted on your progress. Someone down the road will certainly appreciate it as it added to the knowledge base of this forum.

Good luck,

WEK.

[THayes]

Tirod, Thanks for the input, I agree with all you say. The mechanical stuff is fun and grunt work for the most part. Troubleshooting electrical issues is time consuming, but fun as well…just a little more tedious . It absolutely sounds like an intermittent short or open, with no code coming up to indicate where the problem is. All ground wires from the ECU harness plug were rung out and good. Engine is grounded to chassis through a braided grounding strap. All good connections, no excessive resistance tracing through all ground wires. Again, it gets back to the intermittent problem, the problem has to exist to find it. I appreciate your input, I'll keep at it until it's figured out.

[THayes]

Thanks WEK. I'll keep at it and find a shop to work on it if I don't come up with anything. If it would stay dead, it would be easier to find, but it keeps coming back to life after a short time. I appreciate your input.

[THayes]

Thanks Norm, I appreciate the input. I haven't had a chance to get back to work on the problem, but have some more leads on on other possibilities. Thanks for your help.

[THayes]

Michael, Thanks for the help, I believe I purchased a few things from you during the build. Replaced with a rebuilt distributor. Car ran great for a long time, once it started dying on the side of the road, I just don't want to get too far from home with it. Fortunately, it does start back up….five minutes later…or an hour later….but unfortunately, it doesn't stay dead long enough to really troubleshoot. And tough to troubleshoot on the side of the road. I appreciate the input and your help.

[THayes]

Thanks dforthof, There has been some great feed back, all appreciated. Believe me, I shook every wire after the car started back up, just hoping it would die again to at least let me know there was a wiring issue. It would just keep on running…. I'll keep at it, eventually it will show up and stay long enough to find. I just don't want to be far from home when it does. Thanks for the input.

[THayes]

Thanks Jim, Appreciate the links. At the end of the day….I'll certainly learn a little more when this issue is figured out. Thanks again….

[Jeff Kleiner]

It's time to back up and take a different approach since throwing parts at it hasn't helped. The stand alone Ron Francis EFI harness has 4 relays, two of them could shut you down with a no spark condition. Relay "C" powers the coil and TFI module. Relay "D" powers the EEC and injectors. I'd start by checking for power out of them when it's dead. If you find one that isn't putting power out check for both switched and feed power going in. Intermittents are hell 'cause you've got to catch it when it's dead to troubleshoot.

Good luck,
Jeff

[michael everson]

I know it sucks, but replace the distributor and TFI with known good ones.
Mike

[alpine227]

make sure you have power and ground contiuinty at the coil and TFI module when it dies. . Check the relays as stated above, here is a link to TFI trouble shooting on ehow http://www.ehow.com/how-does_5023948_troubleshooting-ford-ignition-module.html might have an answer. Good luck.

[xatudor]

Just a suggestion, pack an overnight bag, faultfinding tools (multimeter, pliers wire etc), print outs of the above suggestions and any found through the links, creditcard for fuel, lunch and water, mobile phone, tell somebody your going for a drive and will be back tomorrow, tell them were your going and go for a drive. The idea is if you plan the time to faultfind it removes any pressure when it does breakdown, you'll be prepared with a plan of attack and can methodically work through it all. If it doesn't breakdown (Murphy's Law) you will have a great weekend of driving your car, if it does breakdown your weekend isn't ruined because that is what you planned for and as you work through your print outs you can hopefully keep a track of what you found and should be able to start reducing the possiblities till you fix/find the issue. Just remember you may have to do this a few times after you find the issue just to be sure.

[Gratz]

Mike, I think the module you were thinking about earlier is the PIP module (don't recall what PIP stands for). I also understand that it's not the easiest thing to replace. The problem I had with my car sounds very similar... would run great then at random times, the engine would just shut off, sometimes it would restart almost immediately... other times I'd sit on the side of the road for a while... and it was VERY disheartening!!... ultimately talked to others and this PIP thing came up, I opted to replace the dizzy and it hasn't been an issue since.
THayes, I know you said you've replaced the dizzy already, but I'd see if anybody is local to you with a 'known good' unit and give this another try... Because it works, the overall 'system' is good, something is intermittent and it sure sounds like you have it almost isolated to the spark side... not a lot of components there... so the wire jiggling that was suggested is another great idea...

Good luck, these intermittent gremlins are the worst!

[alpine227]

PIP is one of the output pins on the TFI (think film ignition) module. This module has a tendancy to have intermitent issues when it's dying (according to the internet). when it gets heat soaked it can drop spark as well. It's the grey module on the dizzy requires a torq bit to remove. Di-electric grease should be put between the module and the dizzy. The module controls the dwell time of the coil as well so could definatly cause spark issues if the coil isn't allowed to charge.

Edit: err I need more sleep. I just read the thread again and noticed you already changed the module.

[michael everson]

Did this ever get resolved?
Mke

[thedonva]

Yes - did you ever fix the problem?

[first time builder]

Inquireing minds want to know OH hell we NEED to know!!!

Kenny