1997 Mercury Grand Marquis - stopped running, won't start

mercury

#1

Just died without warning at a stoplight the other day. Will not start again. Mechanic friend checked everything he could think of…getting fuel through fuel line/filter, all fuses good, all connections good, getting spark, half tank of fuel. We are stumped. Please help!! Thanks


#2

Try to start it while holding the gas pedal half way down, and report the results back.


#3

Nothing. Acts like it wants to start, but doesn’t crank.


#4

Do you smell gas? (Does it seem like it might be flooding?)
If you hold the pedal all the way down and crank for a little bit, that should clear the flood. If you can get it to start that way and keep it running as long as you hold the gas pedal part way down, then I would suspect that IAC (or Idle Air Bypass Valve as it is called on your car).
If you can’t get it to start, but is smells like it is flooding, then I would check the fuel pressure regulator. Pull the vacuum line that goes to it and see if there is any gasoline in it. If so, the regulator is bad.
The next step after this is to check the compression.


#5

“getting fuel through fuel line/filter”

That is meaningless. Does the fuel get to the rail at the right pressure for this car. The only way to know is a gauge.

“Acts like it wants to start, but doesn’t crank.”

I assume that you mean “doesn’t fire up” rather than “doesn’t crank.” Cranking is just the engine turning over/revving when you turn the key. Clarify.


#6

"Acts like it wants to start, but doesn’t crank."
I assumed that he meant that it was firing a little bit, but not enough to keep running.


#7

Try spraying a small amount of starter fluid into the intake and see if the engine fires then. If it does then you have a fuel delivery problem. If it still doesn’t fire then you need to check the valve timing by doing a compression test. The timing may have slipped.


#8

Sorry. But like I said before, I know nothing about cars. So if my “lingo” ain’t quite correct, I apologize.

It does not start. That’s all I know. When you turn the key, it acts like it’s going to start, but doesn’t. I only mentioned “meaningless” info like getting fuel through the line and filter so that people here would know we already tried that.

Don’t have any starter fluid here, so I’ll have to get some and try that. Thanks for the suggestion(s).


#9

I didn’t mean that the info was meaningless. I meant that the mere passage of fuel through the filter doesn’t tell you that your fuel supply is ok. Fuel injected cars are very picky about the fuel pressure - someone needs to put a fuel pressure gauge on it. When that is done one can also easily observe the behavior of the fuel pressure regulator (as mentioned by tardis).


#10

Okay, will try starter fluid and will see if my friend has a Fuel Pressure Guage.


#11

If there is a fuel delivery problem it may be with the injectors not firing.


#12

Hey, I’ve got one more thing for you to try. Unplug the MAF sensor and see if the car will start then. I had a bug stuck on my MAF once and it killed the engine and prevented it from restarting (although it would fire a little bit). If it runs with the MAF unplugged, you need to clean or replace the MAF, or look for a big vacuum leak.


#13

Okay, thanks.

Massive Air Flow, right? Just want to make sure I’m relaying the correct info to my mechanic friend. He’ll be back over later tonight so we can try more of these suggestions.


#14

Mass Air Flow. It’s the sensor sticking in the air intake pipe just after the engine air filter.


#15

Okay. Thanks!