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92 Ford Taurus LX sometimes does not want to start

I have replaced the battery, spark plugs and wires and also replaced the starter in the last 8 months. also I have replaced some fuses and the fuel filter and changed the oil. My car won’t start sometimes. it cranks but will not turn over. The fuel pressure is good and it sounds like it is firing but it will not start. Sometimes it will start right up after a try or two.

Also wanted to mention that when we replaced the battery less than a month ago, we bought some ethanol to help the fuel system and bought some starter fluid to put into it. once we did all this, it ran GREAT for about 2 and a half weeks. it started up every time on the first try. Then a few days ago it started doing what it use to do, start when it wanted to and not a minute sooner.

any thoughts on what this could be would be appreciated.

It cranks but doesn’t turn over? Perhaps rephrase that to something that better describes the situation :slight_smile:

Sounds fuel related. Does it consistently start when you spritz starter fluid into the air intake, then?
Is there a certain timing involved, like does it start when you’ve let it sit for 5 minutes but it won’t start when you let it sit for an hour?

3.0 or 3.8?

What kawasaga is driving at is the fact that “cranking” means “turning over”. The terms are interchangable.

If it runs momentarily when you squirt the ether to it, I’d say it was a fuel issue too. It could be as simple as the filter, but since it’s intermittant, I’d bet the fuel pump in the gas tank is headed south. I went round and round with one a few weeks ago.

What needs to be known, assuming the fuel pressure is good as described, is whether there’s a good spark or not. This car should be a TFI model and those modules are prone to heat failure; especially in summer heat. Symptoms vary.

Another possibility is a failing ignition switch; the electrical part. The cabin blower motor current is routed directly through the switch and over time the switch can fail due to an aged, worn blower which is drawing much more current than normal.
Ford should have routed the blower current through a relay instead of the ignition switch but that’s what the electrical engineers get the big bucks for… :slight_smile:

Mg McAgnick, my interpretation of the reams is “cranking” means the starter motor is engaging, but the engine isn’t running under its own power. Turning over means spark ignites fuel and the engine runs without the starter.

Am I wrong here?

It is a 3.8 engine. and when I say crank but wont turn over is that when I turn the key, the motor sounds like it is about to start but it never actually starts up. The motor is engaging but the car is not. I have tried starter spray in the air intake and it worked maybe the first time or two but then it ended up not working anymore. Also I have been putting Sea Foam into the gas tank but that only worked for about 2 weeks. Now its back to where it started. As for the heating issues, we have checked everything and put stop leak into the radiator and also we have drained the radiator and puke tank and refilled it with antifreeze. The fuel pump relay module is still clicking and I can hear the fuel pump come on when I turn the accessories on. Not sure what else to check for. I’ve been told it could be bad fuel lines but I have no idea.

Also I want to mention to RemcoW that it never seems to have a certain time frame in which it starts. Sometimes we can let it set for about 15 mins and it will start right up. Other times we can let it sit all night long and when I try to start it in the morning, for work, it wont start at all.

Does it ever not start if you leave it for 15 minutes?

doesn’t matter if it’s 5 15 or a full night…it’s random when it wants to start.

Start with the absolute basics - I’d get a spark tester and see if you have spark when this happens.
Here’s one: http://www.harborfreight.com/90-inline-ignition-spark-checker-69023.html

You basically plug it in series with any plug and it will blink when you try to start if there’s spark.

okay so i i get sparks form the coil…and all the spark plugs…i did all the basics…as stated in the original comment from the start xD

Great - are you sure you’re getting good fuel pressure when it does not want to start?
Let’s face it: you got spark. If you’re getting fuel, it should do something providing your valves are operating correctly.

If you’re certain the spark is good when the car is acting up then this means it’s a compression problem (not likely) or a fuel delivery problem.

You might look at the DTC connector and you should see a plug with a tan wire with a green tracer. That wire is the splice branch for the fuel pump relay circuit and also grounds through the ECM.
Run a jumper wire from that plug to ground and you should hear the fuel pump energize and the engine should start. If it does, do NOT leave this wire in place. It’s for test purposes only.

If the pump does NOT run then there are several possibities.
One is a faulty pump relay or pump; or both.
Working from memory here, this car should have a module under the hood (usually on the upper radiator support) and this module controls the main power supply for the fuel pump, A/C, cooling fans, etc. This is called an ICRM, or Integrated Controller Relay Module, and basically it’s a big box o’ relays. These often develop problems in the wire connnector pins and can cause intermittent operation of the fuel pump or other accessories.

If the pump does run when you jump the relay and the engine will not start you need to verify with a Noid light, VOM, or stethoscope that the injectors are pulsing.
There’s more to this process but this is lengthy enough for now. Hope it helps in some way.

i checked the icrm and it’s clicking when i turn the ignition and i do hear the fuel pump come on. since u mentioned the injectors…im starting to think it could be an injector issue. i don’t mind how lengthy ur comment is i need as much info as needed.

Assuming you have spark and fuel pressure, the next thing I would check would be for power at the fuel injectors. A look at the schematic shows they all have a common power source; the ICRM.
The older Taurus and Sable models powered their injectors from an EEC relay and a fusible link and yours shows to be powered from the ign. switch and the 60 amp cooling fan fuse/link.

There should be 12 volts present at the red wires on the injectors. Testing one will be fine as they are all spliced together. If power is present then you need to verify they’re pulsing when the engine is cranked over. This can be done with a Noid light, test light, voltmeter, stethoscope, etc.

If the injectors are not pulsing then you need to check for any DTC codes; possibly related to the PIP signal which should be a 14.
If there is no power to the injectors then post back and we’ll have to go through the process a step or two at a time.

Keep in mind that the ignition module can cause problems like because an ignition signal must be provided by the module before various functions will operate. The initial fuel pump operation when the key is first turned on is an internal function of the ECM and not dependent upon the ign. module.
Those TFI modules are always suspect; especially during summertime. Quite often testing the module does not reveal anything because a module can be faulty, test fine, and not set a code.
Hope that helps some.

Everything u stated ok4450 shows working fine when i took it to a shop. They don’t even know what it could be. It has gotten worse i got it started then turned it off after 5 minutes and now it’s been 2 hrs and it won’t start. Im currently looking for a new car.

Sorry I can’t be of more help. If the engine has spark, fuel pressure, and the injectors are pulsing then it should start and run, even if roughly.

A gut feeling keeps telling me this could be related to the ignition module or to a lesser extent, the ignition switch.
The modules have a history of trouble and when failing may cause lack of spark and/or fuel pump operation.
Ignition switches can also fail due to electrical breakdown from excessive head due to high current draw from the cabin blower motor. This is very easy to check by noting if power is provided to the ignition coil in both the RUN and START positions. This can also be erratic in nature, just like the ign. modules.

To Coles Law, yes you are wrong, turning over means cranking, what you describe is starting and running, The starter “turns over” the reciprocating assembly in the motor.