1995 Neon, starts missing 15miles down the road

ignition
neon

#1

Here’s the thing, I put this commuter back together when the gas prices started climbing, it’s a 1995 Dodge Neon Highline 2.0L SOHC, and here’s the thing, after dropping off 2 kids at school (ignition off each time) it starts missing and the Service Engine light comes on, so after about 15 miles and a nice warm engine, here’s the kicker leave the hood up and lert it idle in the driveway all day and it doesn’t miss once - anyone have a thought on this?


#2

You fortunate that you have one of the last OBDI models, which means that you can recover the trouble codes in your own driveway using the easy key-on, key-off method. It’s very simple. See details over here:

http://www.troublecodes.net/chrysler/

Follow the directions. You will get a series of 2-digit numbers, usually starting with 12 and always ending with 55. Report the numbers back here for further advice.


#3

That one I know - 12,43,55 - 43 is Multiple Cylinder Misfire, unfortunately it doesn’t say why… - anyone know if a Actron Scan Tool will read this PCM (I have one and the connector is the same on the 95 just don’t know if the serial communications are compatible)


#4

This sounds like a problem I had when I was driving in SoDak last summer. What a very smart poster here told me was that it was likely a vaporlock issue due to th ethanol blend used in that area, which turns to vapor at a lower temperature than straight gas. What happens is that since the fuel injection system pumps the gas it doesn’t use back into the gas tank via the return line, as you drive along, it keeps putting gas that’s been warmed by the engine back in the tank. Eventually the fuel that’s getting pumped up is warm enough that it turns to vapor in the lines and the engine starts missing or quits all together.

What should prevent vaporlock on a fuel injected car is the fuel pressure, so usually vaporlock issues will happen if you have a borderline fuel pressure anyways. The first thing I’d do is change the fuel filter and if the the problem persists, you might consider getting the fuel pressure checked.


#5

Your car can also yield OBDII codes. I don’t know if the Actron is properly programmed for your car but give it a try. If it fails, have your car scanned by someone with the proper equipment. I’m guessing you’ll get either:

P1391 Intermittent Loss Of CMP Or CKP, or

P0351 Ignition Coil No. 1 Primary Circuit.

CMP is the camshaft position sensor and CKP is the crankshaft position sensor.


#6

Actron works P0343 Ignition Coil No.1 - think that means the coil pack is going?


#7

forgot is also had Ckt in the info line off the Actron - so coil pack or Crack Sensor?


#8

check cam crank,sync rate,sorry mis read ,that cant be done with an actron,time to pull out the trusty meter,poss sloppy T-belt. clear the codes and see what returns ,so you are not chaseing a ghost ,or old code that was never cleared .


#9

The Actron CP9135 reads codes on my 95 Stratus 2.0L five speed. However I think your ECU may need re flashed in order for you to read codes on 95 models.

These cars had ignition coil packs that tended to get weak. You should OHM out the primary and secondary of the coils and compare with specification. Also These cars are hard on plug wires, those to should be ohm out as well. Cant remember the values off the top of my head, I will look them up and repost


#10

Before starting mark spark plug wires to cylinder location, and remove plug wires from coil pack as well as unplug wire connector on the side.

Spark plug wires should ohm out between 3000 to 5000 ohms. Replace the plug wires if you get readings higher the 5000 ohms

Primary coil pack ohm reading should be between .5 to .6 ohms. Readings should be taken across terminal plug wire post 1 and 4, and then across 2, and 3, obviously you need to pull off the plug wires to do this.

secondary coil ohm readings should be between 11000 and 13500 ohms. Pull off the wire connector on the side of the coil pack, and ohm out terminal B+ on coil pack to both end terminals on the coil pack.


#11

Just noticed you said car was throwing a P0343 Camshaft Position Sensor Circuit High Input. That sensor is easy to replace, and its gasket was prone to leaking oil until the gasket was redesigned.


#12

GREAT catch! WHEW! he almost replaced the crack sensor.

that new gasket has been out for years (since 1995, latter) Mitsubishi had that same crappy engine for 4 miserable years)thats why we call it the OTHER engine(that never should have been)3 head gasket designs(and still puked,EGR flow,MAP sensors.I’ll stop there.in a nutshell. POS! (YES THAT SOUNDS CORRECT). all that said ,there are 2 reasons for cam high input,does not mean sensor took a NAP.test the sensor FIRST.I must admit I made a HUGE pile of CASH,just because of that GREAT engine,so I can’t complain.THANK YOU DODGE! or is it MOPAR=MOCRAP=MO MONEY! (yes I do belive thats it.)

Great job though.