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it has done this several times in busy traffic. car has 260,000 miles one owner car.how do i tell if this is a ignition switch problem? after a minute the car restarts fine. what else could cause this?


huck 13

also this is a manual,
 

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Possible causes include a worn/intermittant fuel pump or an intermittant crank position sensor. There could be other causes but I've heard of these as being common. Any codes?
 

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My car did that after the Camshaft Position Sensor (CPS) failed. But, I did get a Engine Light for that.

What happens when the CPS pukes out....and correct me if I'm wrong.., Is that the computer looks at the Crank Sensor to perform the fuel and ignition timing.

When the computer looks at the crank sensor alone to perform timing, it either lucks out and gets it right....or the piston will be off by 180 degrees and the car will never start until you give it a break and try again.
 

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[quote name='ModMan_70' timestamp='1321495170' post='11214755'] My car did that after the Camshaft Position Sensor (CPS) failed. But, I did get a Engine Light for that. What happens when the CPS pukes out....and correct me if I'm wrong.., Is that the computer looks at the Crank Sensor to perform the fuel and ignition timing. When the computer looks at the crank sensor alone to perform timing, it either lucks out and gets it right....or the piston will be off by 180 degrees and the car will never start until you give it a break and try again. [/quote]
Close, the Computer ALWAYS does the ignition and fuel timing off the Crank Pos Sensor.  It needs the Cam Pos Sensor to sync it, since a 4 cycle engine does 2 crank revolutions for each full cycle of all the pistons. 

If there is no signal from the cam position sensor, it just guess's, and it has a 50/50 shot, if it guess right, then the motor runs fine.  Since the Neon has a wasted spark ignition system, guessing wrong and being 180° off doesn't effect ignition, it was going to fire the spark plug on the exhaust stroke anyway.  It does mess up the fuel timing, but the motor will run, although very poorly, if you inject fuel on a closed intake valve and then the valve opens later and sucks in the puddle of fuel.

I've have seen multitudes of posts about fuel pumps starting to fail by intermittently quitting, but coming back and run again for a little while.  Same for Crank Pos Sensors, without throwing a fault code, people have had intermittent lose of signal, which kills the ignition and fuel, only to have it come back later and have the motor run fine.

  1. Check for Fault Codes, fix what every codes you get and see if that solves the problem.
  2. Perform tests on the Fuel Pump, Crank & Cam Pos Sensors (Keep in mind, since this is an intermittent problem, the offending part might pass the test with flying colors and then just fail for 20 minutes again out of the blue).  Also check out and test the wiring, shorts in the wiring are often intermittent and a short to one of those items would be the same as the item being bad.
  3. Tests or Codes don't tell you anything, I'd replace the Crank Pos Sensor, that is the most likely and cheapest and easiest to replace.
  4. If that doesn't fix it, then the CAM position sensor, even cheaper and easier to fix, but less likely to be the problem.
  5. Before spending all the money on a fuel pump, I'd consider borrowing or buying a fuel pressure gauge and check the fuel pressure.  It could be the fuel pump, but I'd hate to spend $220 on a new fuel pump and all the work to change it, to find out it wasn't the fuel pump causing the problem.
A crank or cam Pos Sensor wouldn't be such a big deal to swap out on a guess, hoping it will fix it.
 

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could it be possible that the EGR valve is bad?
Doubt it. I've had bad EGR's cause a surging and high idle, I could believe them even causing stalling, BUT to cause it to stall and NOT restart until you wait a few minutes, I don't see how a bad EGR does that?

Like I said, either an intermittent short, I've seen numerous posts where this happens with bad Crank Pos Sensor or Fuel Pump starting to die. Check if there are any stored fault codes.
 

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Similar results with my '98 and it was the crank position sensor. She would run awhile after warmed up and then die. after cool down she would statrt and run only to die shortly thereafter. I never got a CEL and could not code her after she cooled down. Took her to a TECH with a BIG codeing device and we let her run until; she died and then instantly coded her and it came up the CPS. Repllaced CPS and no further issues.
 

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Got a 98 sohc that started stuttering then would die but would start right up, then one day it didn't and left me sitting through 4-5 lights(cussing)then I took it to the parts store and they threw a code reader on it and it said cam sensor. Replaced it and it ran great...for about three days and then the same old stuff happened again and their reader was still saying cam shaft sensor however they told me it could be the crank sensor because they are on the same circut.
When I changed the cam sensor I didn't change the connector,so I wonder if maybe I should have.Seems the wires were different or the color codes were but I was in a hurry so I could pick up my boy from work.

Oh by the way runs good for about 10-15 minutes, then it's time to keep the rpm's up until I get home.
 
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