No fule in 4th cyl. At idle on 1998 Plym Neon

Tiny
MREDFARMER23
  • MEMBER
  • 1998 PLYMOUTH NEON
  • 4 CYL
  • FWD
  • AUTOMATIC
  • 130,000 MILES
My 1998 P)lymouth Neon is on 3 cylinders when idling and has engine misfire and is only running on 3 cylinders. When driving the engine is fine. I have been to a few mechanics and I have changed the egr valve, the crank and cam sensors. I have swaped fule injectors, spark plugs and wires and still the forth cylinder gets no fule at idle. You you think of anything that I might have missed in my quest to fix this problem?
Monday, November 22nd, 2010 AT 1:06 AM

6 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 110,176 POSTS
Have you run a scanner while the engine was running to see if there is a fuel or spark issue?
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Monday, November 22nd, 2010 AT 1:12 AM
Tiny
MREDFARMER23
  • MEMBER
  • 3 POSTS
I have had this to a mechanic who scanned it and said that it was the egr valve which I changes and it did not help. I also was told that it was the o2 sensor was hanging up. A scan also reveiled that the vacuum was ok and the compresion check was ok. Could it be a broken valve spring. What should I check next? Could it be the computer, and how would I check for this?
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Monday, November 22nd, 2010 AT 1:44 AM
Tiny
JACOBANDNICKOLAS
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If it is missing only at an idle, to me it sounds electrical. What I ment by the scanner is this. There are scanners that can be used when the engine is running and the vehicle is being driven. That way when the engine miss occurs, it can capture what is happening and from that, the mechanic should be able to pinpoint where it comes from.

As far as a valve spring. You would hear that all the time and it wouldn't change with the RPM's. See if your mechanic can do what I suggested. For some reason, the #4 cylender is losing spark or fuel only at an idle. In my mind, it is an electrical issue. It could be ignition or a loss of power to an injector at idle. If the compression is good, don't let them rip into the engine.

See if they can run a scan during operation. The proper scanner will take pictures of everything that is happening that will then be reviewed by the tech to identify problems.
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Monday, November 22nd, 2010 AT 2:24 AM
Tiny
MREDFARMER23
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Thank you for your advise. I will check with my mechanic and see if he can run the scan you have suggested.
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Monday, November 22nd, 2010 AT 3:24 AM
Tiny
JACOBANDNICKOLAS
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Let me know what you find.

Joe
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Monday, November 22nd, 2010 AT 1:34 PM
Tiny
JACOBANDNICKOLAS
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Let me know what you find.
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Monday, November 22nd, 2010 AT 4:06 PM

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