Mechanics

DODGE NEON ENGINE PROBLEM

1995 Dodge Neon • 133 miles

I got a 95 dodge neon 2.0 sohc one evening I was driving down the road then all of a sudden it started to stubble around 60 mph. I managed to pull over cause it acted like it wanted to die. When I pulled over it died on me. No check engine light came on. I put it in park and start it up again. Then I go to put it in drive then it stalls. I try to start it again then it won't turn over. I wait a few min try it again then it would start. Weird. I had to get it towed home. I replayed the fuel filter, pump, nothing. Took the battery to get it checked it passed. Tested the alternator passed. One day I took the throttle body off cleaned it. Drove it down the street for about 15 min no problems. But as I was going up my driveway and pulled up in front of my garage, it stalled out before I could put it in park. Tryed to start it nothing wait a few min starts right up. I cleaned my injectors nothing. Put a new idle air control valve in nothing. A friend if mine told me its properly the tps. Another friend told me my timing may be off checked that checked out good. I talked to a mechanic at a dodge dealership and he told me it could be a bad torque converter. So my? Is what could be the problem and what do I need to look for next?
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My97avenger
February 7, 2013.




How did you check the timing?

How did you clean the injectors

Roy

I lined up the marks the camshaft and crankshaft to top dead center. I took the injectors out and cleaned them
With throttle body cleaner.

Tiny
My97avenger
Feb 8, 2013.
Wow. We need to straighten out a bunch of stuff first.

When it doesn't turn over, the goal is to keep it that way so we can do some troubleshooting. If you get it to start, there's no defect to be found at that time. Next, be very specific on the symptoms and observations when it doesn't crank. Do you hear one single rather loud clunk from the starter each time you turn the ignition switch to "crank"? If you do, that is not related to the stalling problem. If you hear a very light click from the starter relay, or a rapid buzzing when you try to crank the engine, that could be due to discharged battery. Often enough electrons will migrate out of the plates over a few minutes to allow a short burst of cranking minutes later. You can also have a loose smaller positive battery cable where it bolts to the under-hood fuse box. That can kill the electrical power to the engine. Depending on the car model, you may also see the head lights are dim or won't turn on at all, then suddenly they come to life and the engine will crank fine and start.

"I replayed the fuel filter, pump, nothing"

Don't say "nothing" because that doesn't tell us what happened. Do you hear it run for one second after turning on the ignition switch? If so, it's working. You'll hear the hum. Next, except for diesel trucks, you will never solve a stalling problem on a Chrysler product by replacing the fuel filter. Unless they start leaking, they typically last the life of the car.

It's GM fuel pumps that often fail and cause stalling while you're driving. Chrysler pumps will fail to start up when they're going out but once they're running, they almost never quit while you're driving so you shouldn't even be wasting your time with the fuel supply system.

The battery can cause a failure to crank properly but it will rarely cause stalling. It is common to have worn brushes inside the alternator causing intermittent charging, but you would have seen the "Volts" gauge going down and the "battery" or "check gauges" light would turn on. You can do a quick test on the charging system by measuring the battery voltage. Engine off it will be 12.6 volts if it's fully-charged. It will read 12.2 volts if it's good but discharged. That's the time to suspect the alternator.

A carboned throttle body can cause idle speed or hesitation problems but not stalling while driving. They hardly ever cause a problem so don't waste your time with that.

Chrysler has less trouble with fuel injectors than probably any manufacturer in the world, and you know all four didn't fail at once. You can solve some running problems on GM products by running cleaners through them, but that won't solve a stalling problem either.

The automatic idle speed motor adjusts idle speed, that's all. In rare instances it can cause stalling as you pull up to a stop sign, but it isn't even in the picture when you have your foot on the gas pedal.

You didn't say this but "Took the battery to get it checked it passed" suggests you pulled it out of the car. Doing that erased any stored fault codes but along with all the new parts, it introduced a whole new bunch of variables that is going to complicate the diagnosis. To begin with, the Engine Computer lost its memory so among other things, it will not know "minimum throttle". It will not give you the nice idle flare-up to 1500 rpm when you start the engine, you will likely have to hold the gas pedal down 1/4" to get it to start and to keep it running, and it will likely stall when you slow down to a stop or shift into reverse. Don't go throwing a bunch more random parts at it for that. Meeting the conditions for the minimum throttle relearn to take place is terribly easy. You drive at highway speed with the engine warmed up, then coast for at least seven seconds without touching the pedals.

The throttle position sensor has about the least say in how much fuel goes into the engine and it will not cause a stalling-while-driving problem. It can cause a hesitation on acceleration but that defect would be detected by the Engine Computer, it would set a fault code, and turn on the Check Engine light.

You need a new friend. The camshaft timing is not the issue here, ... Most likely, but if it is, you checked it incorrectly. If the timing belt jumps one tooth, the Engine Computer will turn the Check Engine light on and the stored diagnostic fault code will be "cam and crank sync". At two teeth off the computer will shut the engine down to protect the valves. At that point the engine will not restart until the problem is fixed. Yours restarted and ran normally for a few minutes. Ask your friend how it could run normally if the timing belt had jumped? It's not going to magically jump back when it feels like it.

Where the problem comes in is you took the covers off and checked the relationship of the crankshaft sprocket to the camshaft sprocket(s). That is okay, but even though you found that to be correct, if you have the single cam engine, the valve timing can still be late and the computer will detect that and set the "cam and crank sync" code.

Torque converter? Come on. Chrysler was the first manufacturer to develop a torque converter that locked up at highway speeds to get better fuel mileage. That was in 1977. GM used to have a big problem with theirs failing to unlock when you slowed down, and that would cause stalling as you approached a stop sign. Chrysler never had that problem, but even if it did fail to unlock, you would never know that while you were at highway speed. Typically they lock up at anything over 45 miles per hour and in third or fourth gears. Even if something catastrophic broke inside the converter and it locked solid, the engine would still crank fine, then it would stall when you shifted to "Drive" or "reverse".

The most common cause of a stalling-while-driving problem is the camshaft position sensor. That, however, will not cause a failure to crank. Both of your problems can be related to a charging system problem and that's where I would start. Do not remove the alternator from the engine and cart it off to some auto parts store for testing. Professional load-testing needs to be done on the engine. You can do some preliminary tests with a digital voltmeter. With the engine running the battery voltage must be between 13.75 and 14.75 volts. If it is low, there are more tests we can do before assuming the alternator is defective.

Caradiodoc
Feb 8, 2013.
Hi ASEMaster6371. Sorry for butting in. I was busy typing while you were posting.

Caradiodoc
Feb 8, 2013.
No sweat my friend. You have a great night

Roy

Thanks for the help. Makes so much more sense. I'm no expert
But I'm learning all this. Been working on cars for quite some time but still learning new things while working on them. Still got a lot to learn thought that's why I'm using this web site to get the help I need. I was told at advance auto to test my alternator one way would be to start my neon turn on the headlights, heater, windshield wipers, and then check the voltage. I did checked the battery with all items running listed above and took my volt meter and it read 14.10 volts assuming it is good( the alternator). Do u don't think it's my torque converter? I was thinking it could be something simple.

Tiny
My97avenger
Feb 8, 2013.
I'd have to hear the logic that would lead someone to the torque converter.

Did you do the minimum throttle relearn? If so, do you get the idle flare-up to 1500 rpm when you start the engine? If you do, the relearn has taken place, the automatic idle speed motor is working, and the computer has control of it. NOW if you still have a stalling problem at least it is not idle-speed-related.

So are we pursuing a failure to crank problem or a stalling while driving problem? If both, and we are to assume they're related, I would be looking at the large bolt-on connections in the under-hood fuse box first. I CAN see how that would impact all the circuits involved.

Caradiodoc
Feb 8, 2013.
Got another question. When I hook my terminals up to my battery it makes a noise sounds like something at the motor is got power but when I took my battery out to check to see if it is still good and reinstalled it wouldn't make that noise. Do u know what kind of noise I'm talking about. Like I said before it sound like the components are getting power to them. Guess that's normal. Back to the timing I should recheck the timing again just to be sure it didn't skip a tooth? I just replaced the timing last summer so the belt is still pretty new. But I heard it can still skip if the belt has stretched?
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Tiny
My97avenger
Feb 8, 2013.
It only stalls by putting it into drive. Will still run in drive, reverse, and neutral. What is a minimum throttle relearn?

Tiny
My97avenger
Feb 8, 2013.
Nope. You missed my last questions.

The noise you are probably hearing is the fuel pressure regulator. The ASD relay may turn on for one second and the fuel pump will run at the same time. You could also be hearing the Engine Computer running the automatic idle speed motor all the way closed, then back out a predetermined amount in preparation for starting later. Some computers also turn on briefly when they get voltage applied, then turn off.

Timing belts do not stretch enough to jump a tooth unless they are badly worn or whatever tensioning device is used fails or loosens.

The timing problem only applies to your single cam engine and only when there is a "cam and crank sync" fault code. If the light and code aren't present, and the engine runs normally when it runs, this doesn't apply: To address that code you have to pull the sprocket away from the camshaft and inspect the dowel pin between them. If it is sheared off it will let the camshaft turn slightly. That makes the valve timing late while the timing mark on the sprocket is lined up perfectly. The camshaft position sensor detects that because it is at the other end of the camshaft, not by the sprocket.

When the camshaft turns on the sprocket the equivalent of one tooth is when that fault code will be set. At the equivalent of two teeth the computer will shut the engine down to protect the valves. It does that by turning off the ASD relay which removes power to the coil pack, injectors, alternator field, and fuel pump or pump relay. It usually doesn't get all the way to two teeth because the engine stopped running. In between one and two teeth off is a gray area that can cause intermittent running problems but you will still have that fault code. The code is the clue. The way the story usually unfolds is the owner had a Check Engine light but kept driving, and it seemed to run okay. Eventually it turned into intermittent cutting out, then to intermittent stalling. Finally when it gets to the mechanic, he often finds intermittent spark from just one of the two coils. If you monitor the voltage coming from the ASD relay during cranking, (dark green / orange wire at the coil pack or any injector), you will see the 12 volts pulse on and off randomly when it should be staying on steady. That should be done with a test light. Most digital voltmeters don't respond fast enough to show accurately what is going on.

There is a selection on Chrysler's scanner to relearn the relationship between the crankshaft position sensor and the camshaft position sensor when either have been replaced, or when that dowel pin is replaced, but I have never found that to be necessary. As soon as any of those parts are replaced, the computer relearns them as soon as you start the engine.

Caradiodoc
Feb 8, 2013.

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