My 1983 Continental Mark VI!

[Mainemantom]

Sounds like the simular type problem I have with my 83 MGM. In addition, mine quits when driving down the road whenever it feels like.
Find a really good auto electrical mechanic.

[mercurygm88]

I'm finally getting somewhere, I don't know where but somewhere. It's a random no spark event, but only when starting, it never stalls once it's running. I went to go to work today and no start, I futzed around for 5 minutes and nothing nada, zippo, zilch. So I drove the Grand Marquis. Came home at 9:15 tonight stuck the spark tester on it and cranked it, no spark. I futzed around some more squeezing electrical connectors under the hood and swearing, I was about to call it quits but decided to crank it one more time and voila! It fired right up. I took it on about a 20 minute drive to charge the battery back up and make sure all was well. I still haven't found the wiring to the damn crank position sensor, I assume I'll have to crawl under the beast for that.

Me thinks the previous owner knew this and it's how I got it so cheap, even though it really is true that he only had it a month.

[gadget73]

The high idle is way less advanced than a solenoid. Its a heat choke like carbs use. When cold, pumping the pedal lets the high idle cam drop into position. It has a heater and a vacuum pull-off to lift it back out as it warms up. I suppose if the TPS were glitchy it might be that it lands in a dead spot in the high idle position.

[atlantic3000]

on the issue of the fuel injection not pumping fuel randomly.
try removing all the fusible link eyelets on the starter relay on the passenger fender. sand them until they are shiny and clean and put them back.
when they are oxidized or rusty or loose they can cause intermittant loss of fuel.
also there is a small ground wire on battery. make sure that is good as well. that is ground for fuel system.

[DerekTheGreat]

When you bought the truck was it advertised as not running? I've known some people who got good deals on non running vehicles only to find it was a simple fix...

It was. The CL ad said that he parked it and couldn't get it started. Derek might remember better than I, but I think it sat in the same spot for a couple of months and the guy just couldn't get it started. He said that he had tried and that it would turn over but not fire. We were figuring that we could throw something easy at it like a dizzy or something (stuff that we both have laying around). We dolly towed it back to Derek's place and took us very little time to get it running. It was HILARIOUS when it fired right up! The guy Derek bought it from didn't seem to know much if anything about cars or anything mechanical.

Yeah, the dude said he moved it one day, ran fine that day but he couldn't get it to start several months later. Like Vic said, we got there and figured it would be an easy fix and so we just wanted to get it out of there. I usually poke around and spend lots of time crawling around but the price was right so I just verified it wasn't actually engine swapped with some carbureted junk. Even came with a newish battery! Vic and I had the thing running within five minutes of getting it in my driveway- it sat & idled great, we laughed our asses off. Oil & filter looked like it hadn't been changed in 10+ years although it didn't appear to be using any. I seriously contemplated keeping it and throwing some elbow grease at it or pulling the engine & trans for a cleaner truck. Trashed those ideas when I realized I could triple my money. I think that is the first vehicle I sold at a profit..

I've never heard of more than 2 pumps on an EFI system. Lift in the tank, high pressure on the frame rail is the usual config for multiples. I don't think the Panther cars ever had more than 1 but maybe the very earliest ones did have two. I don't see the mechanical pump being a thing though, not a chance it would handle the pressure or volume involved in a return style fuel system.

The trucks were more common with twin pumps but I think that was more about the dual tank option. Each tank had a low pressure lift pump that fed into the switching valve, then the high pressure went between the valve and the engine. Much easier to switch ~6 psi than ~35 psi. They probably kept it on single tank models just because it was less effort to use a lot of the same wiring, plumbing, and parts.

ok, two lift pumps and a pressure pump is 3 pumps, but only 2 work at a time, so you know what I mean...

Yeah I thought I remembered HisRoyalGhostliness saying the lift pump thing in F-series trucks went away in '89- but this Canadian model truck had it so I think it was actually '90 and up trucks which did away with them. But after looking up pictures of the pump on the frame rail, the diagrams it corresponded to were of the dual/triple pump set up variety. This was a single tank truck. I don't like F series trucks with just one gas tank so one of the factors which pushed me to sell it. Such a cool option, especially trucks without lift pumps.

I believe this mainly because in the month and a half that I’ve been selling automotive parts I’ve come across an amazing number of folks buying parts they think they’re going to change themselves yet they don’t seem to have a clue.

90% of my customers don’t know what engine is in their vehicle, 50-60% don’t know the year, and about 15% don’t even know the make or model. Oh and we can run the plates, but the Ohio BMV is years behind so your Ford Focus could come up as the Chevy Silverado you sold five years ago.

Don’t even get me started on these stupid integrated thermostats and vehicles that have 3 or 4 sizes of brake pad and/or rotor that do not correlate to engine size or trim level. Even the VIN doesn’t help you, you have to measure the rotor.

Wow.. WTF?? Hell, I know a little about cars and even I get intimated to the point I know I won't be touching something. I'd never try to fix something engine related if I couldn't even identify which engine the car had, let alone it's year.

Hmm...... I might be getting somewhere. Just after my last post I ran into town to grab some stuff from the gas station. The car didn't want to start, I pulled the key out of the ignition and put it back in and removed it several times, tried it again and it fired right up. Coincidence? Anything in the lock cylinder that could potentially cause this no start issue? I realize this is not a chipped key or anything, I don't even know if there are electrical contacts for the lock cylinder. I notice you have to get the key angled just right or it only goes about halfway in. Perhaps something with the ignition switch?

I've read around here that ignition switches can cause issues like that...

[mercurygm88]

Hmm...... I might be getting somewhere. Just after my last post I ran into town to grab some stuff from the gas station. The car didn't want to start, I pulled the key out of the ignition and put it back in and removed it several times, tried it again and it fired right up. Coincidence? Anything in the lock cylinder that could potentially cause this no start issue? I realize this is not a chipped key or anything, I don't even know if there are electrical contacts for the lock cylinder. I notice you have to get the key angled just right or it only goes about halfway in. Perhaps something with the ignition switch?

[mercurygm88]

It was. The CL ad said that he parked it and couldn't get it started. Derek might remember better than I, but I think it sat in the same spot for a couple of months and the guy just couldn't get it started. He said that he had tried and that it would turn over but not fire. We were figuring that we could throw something easy at it like a dizzy or something (stuff that we both have laying around). We dolly towed it back to Derek's place and took us very little time to get it running. It was HILARIOUS when it fired right up! The guy Derek bought it from didn't seem to know much if anything about cars or anything mechanical.

I believe this mainly because in the month and a half that I’ve been selling automotive parts I’ve come across an amazing number of folks buying parts they think they’re going to change themselves yet they don’t seem to have a clue.

90% of my customers don’t know what engine is in their vehicle, 50-60% don’t know the year, and about 15% don’t even know the make or model. Oh and we can run the plates, but the Ohio BMV is years behind so your Ford Focus could come up as the Chevy Silverado you sold five years ago.

Don’t even get me started on these stupid integrated thermostats and vehicles that have 3 or 4 sizes of brake pad and/or rotor that do not correlate to engine size or trim level. Even the VIN doesn’t help you, you have to measure the rotor.

[VicCrownVic]

When you bought the truck was it advertised as not running? I've known some people who got good deals on non running vehicles only to find it was a simple fix. One was missing plug wires, another was a locked up A/C compressor, and a third that I recall was a locked up water pump. The missing plug wires were on a very very clean low mileage '92 Mustang GT that was picked up for under $1000 about 7 or 8 years ago by a buddy of mine. He bought it from the original owners widow who just wanted it gone, it was one of the very few stock fox body's I've ever seen.

It was. The CL ad said that he parked it and couldn't get it started. Derek might remember better than I, but I think it sat in the same spot for a couple of months and the guy just couldn't get it started. He said that he had tried and that it would turn over but not fire. We were figuring that we could throw something easy at it like a dizzy or something (stuff that we both have laying around). We dolly towed it back to Derek's place and took us very little time to get it running. It was HILARIOUS when it fired right up! The guy Derek bought it from didn't seem to know much if anything about cars or anything mechanical.

[mercurygm88]

I've never heard of more than 2 pumps on an EFI system. Lift in the tank, high pressure on the frame rail is the usual config for multiples. I don't think the Panther cars ever had more than 1 but maybe the very earliest ones did have two. I don't see the mechanical pump being a thing though, not a chance it would handle the pressure or volume involved in a return style fuel system.

The trucks were more common with twin pumps but I think that was more about the dual tank option. Each tank had a low pressure lift pump that fed into the switching valve, then the high pressure went between the valve and the engine. Much easier to switch ~6 psi than ~35 psi. They probably kept it on single tank models just because it was less effort to use a lot of the same wiring, plumbing, and parts.

ok, two lift pumps and a pressure pump is 3 pumps, but only 2 work at a time, so you know what I mean.


shouldn't be fuel boiling. It doesn't vent to air, but at worst if it boiled it would just push some fuel back through the regulator to the tank. Just being able to keep it under pressure will considerably raise the boiling point of the fuel anyway. One pump cycle should be enough to refill the lines and build pressure. Thats really the magic trick of a return style system, the fuel moves quickly enough that it can't get hot enough to boil, and even if it happens while heat soaking the pump can shove fuel through fast enough that its not a problem. Not like a carb where you have a low volume mechanical pump that has to refill a carb bowl.

Yeah I’m definitely going to have to stick a fuel pressure tester on it next time it happens. If I can get it to happen when I’m at home. If one priming cycle is enough to fill the lines then I suppose it’s possible that’s not it. Is there Anything between the lock cylinder, ignition switch, starter that could cause a random no spark event? The key is mighty sloppy in the lock cylinder.

It never stalls on me just gives me the starting issue from time to time. It hasn’t acted up since Monday “knock on wood” the only thing I’ve done different is I haven’t been pumping the gas pedal once before starting like car like the manual says I should.

Apparently CFI has some kind of high idle solenoid that that sets? I don’t see how this could be related but I haven’t had the issue since I stopped doing that.

[gadget73]

I've never heard of more than 2 pumps on an EFI system. Lift in the tank, high pressure on the frame rail is the usual config for multiples. I don't think the Panther cars ever had more than 1 but maybe the very earliest ones did have two. I don't see the mechanical pump being a thing though, not a chance it would handle the pressure or volume involved in a return style fuel system.

The trucks were more common with twin pumps but I think that was more about the dual tank option. Each tank had a low pressure lift pump that fed into the switching valve, then the high pressure went between the valve and the engine. Much easier to switch ~6 psi than ~35 psi. They probably kept it on single tank models just because it was less effort to use a lot of the same wiring, plumbing, and parts.

ok, two lift pumps and a pressure pump is 3 pumps, but only 2 work at a time, so you know what I mean.


shouldn't be fuel boiling. It doesn't vent to air, but at worst if it boiled it would just push some fuel back through the regulator to the tank. Just being able to keep it under pressure will considerably raise the boiling point of the fuel anyway. One pump cycle should be enough to refill the lines and build pressure. Thats really the magic trick of a return style system, the fuel moves quickly enough that it can't get hot enough to boil, and even if it happens while heat soaking the pump can shove fuel through fast enough that its not a problem. Not like a carb where you have a low volume mechanical pump that has to refill a carb bowl.

[mercurygm88]

LoL yup, $200 for a truck which ran, drove and stopped

I studied up on it and it turned out that '89 trucks still had two pumps- there is supposed to be one in the tank and then another right on the frame- so that fuel pump we thought was hacked in place is actually supposed to be there. Whoever worked on it just didn't put the pump back in the cradle and wired the thing directly to a switch. I did some tests and I never had power at the factory wiring for that pump. Didn't realize it only supplies power when the engine is cranking, but figured there should be a burst to prime it. Never heard the in-tank pump run at all, so I wanted to run it as little as possible as not to burn out that pump on the frame rail. Think those dudes were like $150...

When you bought the truck was it advertised as not running? I've known some people who got good deals on non running vehicles only to find it was a simple fix. One was missing plug wires, another was a locked up A/C compressor, and a third that I recall was a locked up water pump. The missing plug wires were on a very very clean low mileage '92 Mustang GT that was picked up for under $1000 about 7 or 8 years ago by a buddy of mine. He bought it from the original owners widow who just wanted it gone, it was one of the very few stock fox body's I've ever seen.

[DerekTheGreat]

There is a hack way of doing it.... I saw this on an '89 F150 I helped Derek pickup last year. Someone had put an inline fuel pump on the truck because the in tank pump presumably died. In fact, this hack job was the reason he got it for so cheap, it wouldn't start. Turns out the hack wiring was loose or not making good connection at the inline pump, the truck started right up when we wiggled that wiring and we laughed our asses off when it started after 30 seconds of work.

LoL yup, $200 for a truck which ran, drove and stopped

I studied up on it and it turned out that '89 trucks still had two pumps- there is supposed to be one in the tank and then another right on the frame- so that fuel pump we thought was hacked in place is actually supposed to be there. Whoever worked on it just didn't put the pump back in the cradle and wired the thing directly to a switch. I did some tests and I never had power at the factory wiring for that pump. Didn't realize it only supplies power when the engine is cranking, but figured there should be a burst to prime it. Never heard the in-tank pump run at all, so I wanted to run it as little as possible as not to burn out that pump on the frame rail. Think those dudes were like $150...

[mercurygm88]

Thanks for the ideas everyone. I'm still going to look when I get the chance and see if there's a port to check fuel pressure. No sense replacing the pump if it turns out I have fuel pressure when this happens. I can't possibly think of anything else though, I have spark for sure, and if it turns out I have fuel too then it doesn't make much sense. If I could replicate it at home it would be easier to diagnose but that only happened the first time. Ever since then it seems to only happen when I'm trying to leave work or stuck in some other parking lot with no tools.

[atlantic3000]

never have hot start issues on my 83 mark 6 in fl

[Tiggie]

If it starts nicely after cycling the key several times, sounds like the fuel pump check valve to me.

I doubt it's the fuel boiling off in the CFI unit. It's an interesting theory but I just can't see it happening. A high pressure fuel pump will usually fix that and cause the vaporized fuel to liquify. Carbs vent to the atmosphere or a carbon canister, so the vapor leaves. I don't know if CFI vents or not, I suspect not.

Fuel pump isn't the worst job in the world. I'd give it a go if you continue to have problems with it.