I have a 1992 Plymouth Acclaim that enjoys stalling. It doesn’t do it very often - maybe once every 100 times I turn it on. But I reckon I ought to do something about it before I stall somewhere really inconvenient.
It’s most likely to do it:
After I’ve turned the car off without putting it in park.
On days that are between -5 C and 10 C when the air is moist.
It only stalls when I’m going slowly. (But maybe that’s when all cars stall… I don’t know this stuff.)
Thank you very much Straight Dope message board, which is much cheaper than a mechanic!
While you did give us some information about when the cars stalls, there is still more that we should know. Does the car stall right after start up, or after you have been driving a while? Does it only stall when driving slow, or when you are stopped at a traffic light also? What, if anything have you done to the car since you noticed the stalling? When was the last time you had the spark plugs, air filter, changed?
While we are waiting for some more info, let me venture a few educated guesses.
It could be fuel related, try a different brand/grade of gas.
If the air filter is dirty or the spark plugs are worn the car may be more prone to stalling (see question above)
3)Fuel injectors could be dirty giving a poor spray pattern causing the car to be prone to stall esp cold.
idle speed cold be too low causing stalling. Does the car have a tach? If so what is the idle speed in gear?
Also you mentioned the temp as a factor, summer is comming and nature may cure your problem for a few months anyway
Often it will restart after a couple tries, but sometimes (say, when I’m stranded in a town some hours away) it just won’t! The RPM will go up to 2000 or so and then quickly drop.
Sometimes this can be remedied by quickly putting it in drive and stepping on the gas and driving - which will usually cure the car for a while.
The car stalls sometimes at startup and sometimes when I’ve come to a stop.
If it stalls at startup, it’s more likely to work soon after. If it stalls after some driving it’s more stubborn.
It stalls roughly equally each way.
It stalls sometimes when driving slow- the RPM drops and keeps dropping.
We got a new transmission about 2 years ago and it’s been stalling for about 3.
The air filter should still be good and the spark plugs… I don’t know and the spark plugs don’t need changing yet my paw (the former owner) says.
In Question 4, I don’t understand what a tach is:
I don’t think it runs rough all the time, but I have heard it hoarsely whisper “Stupid Jen… I’m so sick of her. I’m going to stall in this far-away town! Ahaha! That’ll learn her!”
I had my fuel injectors only changed once in the life of my car. (His name is ‘El Carro, the Jenmobile’). This must have been 10 years ago when there were 50,000 km on my car. My dad says he’s put some fuel injector cleaner in from time to time.
This may not fix your problem completely, but if it caused a problem in the past, might be affecting this.
Drain your tank as low as you feel comfortable. Buy a bottle of Chevron Techron Concentrate, dump contents into tank, then fill it up with mid grade gas. (Chevron/Shell/Texaco/Mobil/Sunoco all have detergents in the gas, which should help keep those injectors clean in the future).
When you finish that tank, fill it up at least once more with mid-grade, then go back to regular. If this makes an improvement, but it still isn’t perfect, you might want to consider having the injectors professionally cleaned.
BTW, the rev up after you start is normal for cold starts.
I had the same problem with my 1994 Plymouth Acclaim. My mechanic said the problem was with the oxygen sensor and replaced it. The car ran fine for about 6 months then had the same problem. The mechanic again said the problem was the oxygen sensor and replaced it a second time. The car has been running fine and it’s been about 2-3 years. Good Luck
My '90 Ford Probe had this exact problem (twice) with identical symptoms described by OP. It was indirectly oxygen sensor related. In that car there’s a flexible duct that leads air to the air filter, (the name of this part escapes me). This duct was made of a rather flimsy substance, almost like a heavy grade paper. Turns out it had torn. Under the situations you described, the duct would flex and “open” the tear. This wreaked havoc with the air flow; basically confusing the oxygen sensor and the car would stall.
Simply replacing the duct fixed the problem both times.
Unfortunately the damed duct wasn’t cheap.
O2 sensor, spark plug wires, PCV valve, fuel filter, fouled plugs, nuetral safety switch. Could be a lot of things. Do not fill it with Mid Grade gas. That may burn too hot for that little engine. To check the wires, get a spray bottle filled with water and spray it in your engine compartment at night. If you get a light show, that means your wires are arcing and grounding out, reducing spark. Will jiggling the keys in the ignition change anything? Futzing with the gear selector? When it is puttering, does it help to take your foot off the gas for a sec? Try to add a bit more info, even what you may consider mundane.
Thank you all VERY much for your help and suggestions!!
Would jiggling the keys be going from on to off?
If so, that often helps.
I don’t know about the gear selector. I don’t think it changes anything because when it feels like being dead, it’s dead in all gears.
When I’m driving slow and it’s about to stall (the RPM drops too much) I can keep it going by giving it some gas. When the RPM is dropping it has a subtle dying feeling, but I have to be quick before it’s down to 0.
Mid grade gas will definitely not burn too hot for that or any other engine. There is absolutely no difference in the potential energy between fuel grades. The octane rating is simply a measure of when the gas burns instead of exploding. Carbon deposits can cause the gas to explode in the cylinder instead of burning smoothly. This leads to detonation, where a portion of the available energy is released before the piston is on its downward stroke. This can cause rough idle and loss of power.
Mid grade can delay the start of combustion until the piston is in the proper position (just before top dead center). In other words, it delays the timing.
The suggestion about spraying the spark plug wires was good though. Fun to watch, too.
Are you sure you don’t mean Mass Air Sensor? The oxygen sensor is located in the exhaust manifold, and tells the Electronic Control Unit whether the car is running rich or lean.
The Oxygen sensor can cause problems, and they do tend to go out fairly regularly on American cars. Just replaced one on a 92 Chevy Cavalier and it took all of 5 minutes. Sensor cost $21.95.
Just goin with my boy’s Tom and Ray over at [http://cartalk.cars.com/]Cartalk I can’t find the specific show that they spoke of heat and the finer points of explosive timing, but I came up with this gem:
the gist of what they said was the pre-ignition due to too low an octane for a specefic engine, or delayed ignition due to an octane too high, can both cause engine over heating. Never a good thing in the small aluminum engine described in the OP. I think we’re actually agreeing on what gas does to ignition timing, I’m just going off what my boys have said in the past. If it wasn’t so late, I’d try digging it up.
Tom and Ray are awesome, and dead on with the details of how octane works (of course). I believe the question they were answering had to with whether there were a performance benefit, not as a possible fix for timing problems. (just a guess)
My suggestion was actually a way to test if pre-ignition were a problem in her car (carbon deposits, ECU problems, timing belt, etc…). The first tank cleans the injectors, the second is your test case. If the car performs differently when you switch back to regular, then it may be worth having the timing looked at by a professional. The experiment is a very cheap diagnosis tool, but could be an even cheaper band-aid if she is experiencing pre-ignition.
BTW, the slight chance of overheating from delayed ignition is why I didn’t recommend going to “Premium” grade.