# Hard start, mercury villager



## cjm94 (Sep 25, 2011)

Fuel pumps are common to lose prime. They have a check valve that goes bad. With a fuel psi Guage cycle key on, you should get about 50 psi and it should hold if it bleeds down. You have a leak.


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## Bigplanz (Apr 10, 2009)

Thanks, I thought about fuel pressure as a possibility. If it turns out to be a fuel pump it's going to the graveyard.


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## 1985gt (Jan 8, 2011)

To test the fuel pump turn the key on and off 5-6 times in a row letting it sit in the on position for a few seconds each time. If you do this from a cold start and it starts right up it narrows down your problem. 

Another thing to check is after it has run for awhile turn the van off and pull the vacuum hose to the fuel pressure regulator, if fuel runs out the regulator is bad.


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## ukrkoz (Dec 31, 2010)

You running rich and fuel fouls the spark plugs. That's why it starts fine on hot - fuel evaporates. You have leaking injectors or your ECM is skewed or one of the sensors, like O2, tells ECM that you run lean, so it pumps more fuel.


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## Bigplanz (Apr 10, 2009)

I tried turning the key a couple of times. Started ok even when cold. Must be fuel pressure related.


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## cjm94 (Sep 25, 2011)

Sounds like fuel pump leaking down if it was an injector or or regulator on the rail you would notice a rough run at startup from a flooded cylinder


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## 1985gt (Jan 8, 2011)

I agree, one way to check the fuel injectors would be see if your oil is over full. Another thing is if it was an injector sticking you would be having drivability issues all the time. 

Id start with the regulator, A quick google search showed them to sometimes be faulty on those vehicles. Plus it's the cheaper and easier part to replace if it is bad.


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## Brainbucket (Mar 30, 2015)

I would stick a fuel pressure gauge on it. Should be between 35-45lbs running with 35lbs at idle and 45lbs with fuel pressure regulator vac hose unplugged. Then turn key off and watch gauge. It stays, your good. If it leaks down, pressure dropping of, then we have a problem. 3 things to check. Easiest is to unconnect the fuel return and have something to catch fuel in a ventilated area. Turn key on and watch fuel pressure rise and then stop. Pressure will start dropping off and fuel will come out of return line until 45lbs is reached, and then fuel should stop coming out of return. If it continues, you have a bad regulator. If it stops coming out of return but pressure keeps falling, either injector is leaking fuel, ( and you would have a miss on start up then it would go away) or the check valve in the fuel pump is allowing fuel to drain back into tank. Replacing fuel pump is the only fix for that. Get a strainer and fuel filter also. Cycling key is a fuel pressure test that directs me to fuel pump test. Cycle key 3-4 time for 3 seconds on time, 5-10 seconds off time. Some are quicker to respond. If it starts right up, whoop, there it is.:thumbsup:


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## Bigplanz (Apr 10, 2009)

I turned the key to run, heard fuel pump run five seconds the key off, turn to start. Started right up. There is a gas smell which my kids notice but I don't (allergies). I bought a fuel pressure tester and the test procedure is pretty straight forward. Pressure regulator is easy to get to. I will replace the fuel filter, while I have the line off. I will shot a video and post it.


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## Bigplanz (Apr 10, 2009)

Oh, I was under the impression that the check valve/roll over shut off valve was in a separate assembly and not part of the fuel pump. Is that incorrect?


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## 47_47 (Sep 11, 2007)

Your roll over (inertia) switch is not part of the pump. The check valve that may be not holding and giving you a long crank is part of the pump.


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## Bigplanz (Apr 10, 2009)

Ok thanks. There is a red button under the dash to reset the fuel pump if the car is in a crash. I guess that is the roll over switch too. Letting the pump run for five seconds seems to resolve the issue for now, but I will do testing on the fuel pressure this weekend.


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## Brainbucket (Mar 30, 2015)

If you smell gas, find out where the leak is. that might be your problem leak down. It will be wet where ever the leak is. Also the evap purge valve stuck open will cause an extended crank as the fuel vabors will enter the intake and flood the motor before start up on extended cold soak. (Vehicle sat over night Saturns were bad about that.) Fuel pressure test will reviel which way to go. But you say you cycle key and all's well. Sounds like check valve in the fuel pump.


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## ukrkoz (Dec 31, 2010)

Didn't I say - you running rich?


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## 1985gt (Jan 8, 2011)

ukrkoz said:


> Didn't I say - you running rich?


A rich start condition doesn't explain why when he cycles the key a couple of times it starts right up.

Fuel is leaking down some how, no you just need to track it down. A ruptured diaphragm in the regulator would cause a leak down in pressure, a rich start condition, and possibly an external leak. 

If there is a gas smell it may be a bad fitting or ruptured line somewhere. I'd definatly be tracking that smell down. A fine mist of fuel on a hot engine is a terrible thing. Unless your family is not around and of course you are tired of this headache of a van! :laughing:


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## ukrkoz (Dec 31, 2010)

Maybe ECM adjusts for something. I don't know. Maybe EVAP or bad EGR is loading petrol back into the CC-s. Running rich = petrol smell. From my Ford times, they had oddly shaped injector O-rings. Those may leak too. Does not have to be stuck injector.
Maybe when he cycles with the key, EVAP opens purge valve and rids of excessive petrol. I tossed initially most common causes but was apparently correct on one - RICH condition.
That van is something. Man must be real masochist to still keep it.


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## Brainbucket (Mar 30, 2015)

Always check the basics. More often then not, that's what it is. I still say fuel pump. I had a truck come it and he said when he killed it, it wouldn't start. It had fire, pulse, compression, fuel pressure, PCM was giving info, Stumped my fellow techs. I went over and got a fuel sample. Water with the hint of gas smell. He didn't tell me he had just got gas and didn't make it out the parking lot. For you older mechanics, remember when a car would come into the shop and all the mechanics would guess what was wrong with it before it was diagnoised? Can you do that now? Not as much as there are more systems to make the same type of failure. But I still do it...lol:thumbup:


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## Bigplanz (Apr 10, 2009)

I found a vacuum line from the egr solinoid pulled loose yesterday. Plugging it back on seems to help gas mileage anyway. More testing ahead. Got sidetracked putting the window back in.


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