My ford taurus (1995) is acting up again. It was running fine this morning, but when I went to start it this afternoon it started up with the normal sound but died after a few seconds. I tried this a two more times with the same result. I gave up and got it towed to the shop. The tow truck guy was able to pull it out onto the street. I checked the antifreeze and the oil and they both seemed fine. What could be causing the problem?
There’s not enough info known to be able to get specific was we don’t know what’s missing; fuel, spark, both, etc.
The 1995 model should the last of the TFI module engines. This is the ignition module which is prone to failure. Fuel pump, CCM module problem, ignition switch, etc are possibilities.
What needs to be determined first is whether it’s lack of spark or lack of fuel. This is easy to do and no matter the problem it should not be hard to sort out. The fuel injection/engine management system on these cars is comparatively simple.
I think you mentioned in another thread the alternator was replaced recently. I’m guessing there’s something wrong with the new alternator installation and the battery has gone dead.
I never had any trouble with the battery and had just driven it, but they could always test the battery anyway since I have no idea how long it has been in the car.
"you mentioned in another thread the alternator was replaced recently. I'm guessing there's something wrong with the new alternator installation and the battery has gone dead."
+1
Because the alternator was apparently replaced earlier in the day, I think that this is the most probable scenario. So, the car must be taken back to that mechanic–on a tow hook, I guess.
“they could always test the battery anyway since I have no idea how long it has been in the car.”
This suggests to me that you may have recently acquired this 21 year old car. You have to bear in mind that any and every component on a car this old can fail at any time. And, if you don’t know the full maintenance history of the car, that introduces the probability of additional reliability issues.
I’m going way out on a limb here and say that your battery is the most likely suspect.
I can have them check the battery. The mechanic said they have tested it several times and it starts every time. They have looked under the hood and didn’t see anything that looked wrong. He said something about vapor lock, but I don’t know anything about what that is although he explained it to me. The car is still there since they decided to do a few more checks tomorrow to see if they missed anything.
don’t know if it makes a difference but it was in the 90’s outside that day
I’m with @ok4450 on this one. The OP states that it will start repeatedly then stall. I doubt it’s the battery or alternator.
21yrs of new mex heat? Any decayed vacuum lines? I know the 2000 era motors had a PCV elbow that rotted and caused stalling.
I too am with OK4450. If the car starts and then dies shortly thereafter, the battery is not causing this problem.
I read up on vapor lock and it sounds like a probable cause. ;will find out from the mechanic this morning.
Vapor lock almost never happens with fuel injected engines.
“Vapor lock almost never happens with fuel injected engines”
+1
If the OP’s car was built in the '50s, '60s, or '70s, or perhaps even in the very early '80s, then I would agree that vapor lock is a possibility. However, a mechanic who provides that diagnosis on a car built in the mid '90s is…suspect…in my opinion.
“Vapor lock almost never happens with fuel injected engines”
Another urban myth.
Vapor lock can and does occur on fuel injected engines.
A fuel injection system has a feature called residual fuel pressure. This means when the fuel pump stops operating the system remains under pressure for a certain period of time. Then the fuel pressure slowly bleeds down. This feature prevents vapor lock from occurring when the engine is shut down when hot.
If the residual fuel pressure immediately drops to 0 PSI when the fuel pump stops operating, and the engine is hot when it’s shut down, you get vapor lock.
Tester
"Another urban myth."
Perhaps that is the case, but I can attest that I haven’t experienced that problem since the days of driving my father’s '63 Plymouth, and that covers over 5 decades.
If I never experienced vapor lock in my cars of the '80s, '90s, and beyond, just how common is that condition?
As common as the anti drain-back failing on a fuel pump.
I’ve replaced fuel pumps for both reasons.
But then, I work on a lot more vehicles than you do.
Tester
“Vapor lock” means the gasoline is boiling somewhere in the fuel lines which turns it into a gas instead of what it should be, a liquid. It days of carbureted- engine yore it was a very common thing causing “cranks but doesn’t start” b/c some hot part of the exhaust system would heat up a nearby fuel line, and the fuel pump was attached to the engine block, so it had to pull the fuel out of the tank rather than push it. Then the fuel pump wouldn’t move the fuel, and the engine wouldn’t get a supply of gas so it wouldn’t start.
But vapor lock isn’t a common problem with modern fuel injected engines like your Taurus has, where the fuel pump is probably in the tank and pushes the fuel towards the engine. It seems like vapor look could only become a problem in that configuration if the fuel lines ran on a downward slope at some point, where gas in the line would create a buoyant force opposing fuel movement, but I doubt that’s the case w/your car. Suggest to discount the “vapor lock” theory.
Good idea to have the battery tested to make sure it is fully charged. OK’s idea above is a good one to check too. Especially if this problem only occurs when the engine is at normal running temperature, especially if it has been recently shut-off, then it won’t start when you try to re-start it after 15 minutes or so. That can be caused by a failing part in the ignition system or a faulty crank or cam position sensor. All those tend to have heat-related failure modes.
Yeah, vapor lock can occur in a malfunctioning fuel injection system that can’t hold residual pressure due to a bad check valve in the fuel pump or a forward leak in the pressure regulator but not in a properly functioning fuel system.
I think the assumption here is that the fuel system is working properly.
Back in the days of carbureted systems the diaphragm type of fuel pump was mounted on the engine block in the midst of high heat which could vaporize the gas at the fuel pump and that type of fuel pump can’t pump vapor.
When the fuel pump is mounted in the relatively cool gas tank submerged in the gasoline it can immediately pressurize the system. The pressurized gas will immediately condense back to gasoline.
Bear in mind the OPs car had this problem after cooling down for a few hours.
Another thing that prevents gas from vaporizing in the engine area is that fuel injected systems are constantly recirculating the gas back to the fuel tank which cools it.
If the engine keeps starting up and then dies, it seems to me that something is shutting the engine down. If this vehicle has something like a oil pressure sensor shut down circuit installed on it then maybe it isn’t working like it should be. Don’t some Ford models have that kind of thing?