My 1983 Continental Mark VI!

[slack]

My friend has an 83 CV EEC III with CFI and AFAIK, he only has the one pump in the tank. I know there's definitely none on the engine. Not 100% sure on the fuel rail, but I don't recall one. I know he has a special 83 specific fuel filter that screws on though.

Also, about the fuel boiling out on CFI. Not sure on CFI units but I thought that was the case on my 78 with a 2150 carb when I first got it because it was a PITA to start when hot. Turns out it was just the carb in dire need of rebuilding. I rebuilt it about 5 years ago and haven't had a problem starting it since (probably just jinxed myself). My experience with CFI is only second hand through my friend's car so I can't really weigh in on that. I had TBI on my 82 Deville before the HT4100 ate itself and also never had issues with starting hot.(Only mentioning because it's the GM equiv. to CFI)

[mercurygm88]

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.

That reminds me of the rumors I've heard about CFI fuel pumps. I once read EEC III CFI cars had 3 pumps in 1980. One in the tank, one in-line, and a mechanical pump on the engine. I've also read that all EEC III vehicles had the in tank and in-line pump. Another member here mentioned their Mark VI had no in-line pump but their CFI F150 did. The parts system at work lists an in tank and in-line pump, I haven't been under the car to look. I'm hoping their ends up being a simple non hack job solution once I 100% know what's going on.

I don't like hack work, even on the rare occasion that I do hack work. I'm still slightly upset about a previous owners hack radio install. It's not so much the aftermarket head unit as the fact they chopped the factory connector out and wired it to constant power because they were too cheap to buy an $8 harness, I have to take the faceplate off to turn it off. They also lost about half the dash trim screws, I fixed that, and they shot two random machine screws through the trim to the left the radio that shouldn't be there. Not to mention they mutilated the rails for the ashtray so it won't go back in. Luckily those are the only two hack jobs I've found on the car.

[mercurygm88]

eec-iv has it somewhere on top of the CFI unit, not sure about yours but if its anywhere I'd expect it to be there. Pop the air cleaner, should be right there on top where the two injectors are.

I'll have to take a look and see, at this point I can't really come up with any other ideas about what it could be. I did see some people on the Ford truck form talking about modern gas evaporating in CFI systems on hot days. That could potentially explain why it's fine when it sits in my garage over night. I suppose that could also be B.S.

[VicCrownVic]

Hmm..... There doesn't seem to be an easy way around this then. I wonder how many starters I'll go leaving it as is? Maybe I can find the correct number of times to turn the key to on to fill the lines every time.

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.

[gadget73]

eec-iv has it somewhere on top of the CFI unit, not sure about yours but if its anywhere I'd expect it to be there. Pop the air cleaner, should be right there on top where the two injectors are.

[mercurygm88]

Do the CFI cars have a test port for fuel pressure like the SEFI cars do? I would imagine so but I haven't looked for it. That would help to confirm my suspicion.

[mercurygm88]

Its driven from the ECM, and it only gets turned on when it sees crank rotation. Slightly later ones can be hot-wired so the pump is on any time the key is on by adding a jumper in the self-test connector but I have no idea if EEC-III also has that.

Probably a couple of reasons that it works like it does. One is likely to keep the engine from flooding in case of a leaky injector. Also probably something about safety in the event of an accident. If the inertia trip didn't kick and a fuel line was ruptured it would just keep pumping even if the engine stalled. May also be to reduce current load when the engine isn't running.

Hmm..... There doesn't seem to be an easy way around this then. I wonder how many starters I'll go leaving it as is? Maybe I can find the correct number of times to turn the key to on to fill the lines every time.

[gadget73]

Its driven from the ECM, and it only gets turned on when it sees crank rotation. Slightly later ones can be hot-wired so the pump is on any time the key is on by adding a jumper in the self-test connector but I have no idea if EEC-III also has that.

Probably a couple of reasons that it works like it does. One is likely to keep the engine from flooding in case of a leaky injector. Also probably something about safety in the event of an accident. If the inertia trip didn't kick and a fuel line was ruptured it would just keep pumping even if the engine stalled. May also be to reduce current load when the engine isn't running.

[mercurygm88]

If I'm not mistaken, and I very well could be, the check valve is part of the pump itself.
If you can reproduce the issue every time in the morning or after the car has been sitting try turning the key multiple times to the run position but not as far as the start position. After doing that several time the pump should prime the lines and if it starts right up then your suspicion of fuel would be confirmed. This assumes you have an electric in-tank pump like the sefi boxes up to '89 that I'm used to dealing with, which I'm pretty sure it does.

That's what I've been doing and it's been working but it's still annoying. The issue isn't always repeatable at the same intervals. Usually it takes 8+ hours until I have the issue, yesterday it was about 20 minutes after I shut the car off, today about 2 hours. Yet I let it sit for over 12 hours last night and it fired right up when I went to work this morning. Other times it's gone up to 3 days without giving me an issue.

According to the records I have the pump was replaced about 15,000 miles ago, but that was also back in 2002. I have service records going back to 1985 with no apparent gaps showing that this car has 33,000 mile on it. The title says 132,000 because either someone didn't know or the title department pulled their typical crap with 5 digit odometers. Ohio usually doesn't do a forced mileage discrepancy but it can happen. All of our title departments/registration offices are privately owned and run now and none of them seem to know what's going on.

I have no intention of replacing the fuel pump unless I absolutely have too, I wonder if there is a simple way to get the pump to continuously run when the key is in the run position? Or if that would negatively affect anything?

[VicCrownVic]

If I'm not mistaken, and I very well could be, the check valve is part of the pump itself.
If you can reproduce the issue every time in the morning or after the car has been sitting try turning the key multiple times to the run position but not as far as the start position. After doing that several time the pump should prime the lines and if it starts right up then your suspicion of fuel would be confirmed. This assumes you have an electric in-tank pump like the sefi boxes up to '89 that I'm used to dealing with, which I'm pretty sure it does.

[mercurygm88]

So I'm trying to narrow down this random no start issue. The car always ends up starting eventually and once it's running it's good, and will re start just fine if I shut it off. The issue seems to arise after it sits for 8 plus hours. I've determined that any time it happens I do in fact have spark, I also know that the fuel pump is running. My guess is that when the car sits all of the fuel in the lines runs back to the tank, and when I go to start it I have to refill the entire fuel line from tank to engine. So I guess my big question is what is supposed to keep fuel from returning to the tank when the car isn't running? I'm thinking that is what I need to look into.

[gadget73]

there is a temperature vs cycles per minute chart in the service manuals but generally over 80 or so it runs pretty steady, especially at idle.

[mercurygm88]

Yah, what K wolf said. You know it's probably good if it's hot as balls yet the compressor never cycles, at least at idle. If is cycling, probably low and or other issues lurking. Not an A/C guy, but like the Lynyrd Skynyrd song, I know a little.

Good to know, it was about 85 degrees with equal humidity.

[DerekTheGreat]

Yah, what K wolf said. You know it's probably good if it's hot as balls yet the compressor never cycles, at least at idle. If is cycling, probably low and or other issues lurking. Not an A/C guy, but like the Lynyrd Skynyrd song, I know a little.

[mercurygm88]

On hot days, the A/C compressor will seldom cycle, if at all. When it’s a bit milder you’ll catch more normal cycling activity.

Thanks, that was quick.