Topic: Check engine flashing and running rough

[dexetr30]

My wife was on her way to work today when the check engine light started flashing. Soon after the engine started running rough. Checked the codes and nothing. It's a 2002 with a 2.5 and an auto trans. I recently (late last week) replaced the cylinder head, exhaust manifold and the radiator. Any ideas? Some help would be greatly appreciated.

[dexetr30]

One thing I forgot to mention (and temporarily forgot altogether) is that yesterday I thought I had heard a ticking sound coming from the distributor side of the motor. Very faint but definitely there. Sounded exactly like a plug wire was arching/shorting out. I wiggled the plug wires around a bit and changed their positioning so they weren't so close. Now today, this.

[sharpxmen]

if the CEL came on and started to run rough there should be a code stored, i've seen OBDII not displaying the codes but can be read with a scanner (happened to our Caliber). Otherwise there's little to go by from your description, since you mentioned the distributor i'd say start with ignition components from coil onwards, make sure there's no corrosion and if you didn't do it recently replace wires, cap, rotor and plugs

[VA_YJ]

In addition, you can pull the plug and coil wires (by the boot) and check the resistance of each wire if you have a meter.  Higher resistance on a particular wire indicates a problem.  You can also run the motor at night with the hood open and look for arching.

[neale_rs]

In addition, you can pull the plug and coil wires (by the boot) and check the resistance of each wire if you have a meter.  Higher resistance on a particular wire indicates a problem.  You can also run the motor at night with the hood open and look for arching.

X2 on running it in the dark.  Have found bad plug wires that way before.

[dexetr30]

I'll be back in possession of the Jeep shortly. I'm going to give it a going over and I'll post what I find (if anything) once I do. Thanks to everyone who has responded so far.

[sharpxmen]

the cap/rotor, wires and plugs are so cheap that i would just replace them (unless you recently did that).

[dexetr30]

I recently replaced the cap, rotor, wires and plugs.

Pulled the codes. The only thing showing is P0201. Bad injector? Where to go from here?

[Jeffy]

I recently replaced the cap, rotor, wires and plugs.

Pulled the codes. The only thing showing is P0201. Bad injector? Where to go from here?

Check the connectors at the top of each injector.  Reseat each one.  Check for broken clips on the connectors.

[dexetr30]

Check the connectors at the top of each injector.  Reseat each one.  Check for broken clips on the connectors.

Here's what I did.

I removed the injector and moved it over one position on the fuel rail. So, I swapped the first injector for the second.

Put everything back together and fired it up. Still ran lumpy. I turned the engine off and checked for codes again. Now the codes are reading P0202 and P0320. What's the deal?

[neale_rs]

Looks like one injector is bad first of all. And maybe your crankshaft sensor is bad too, but it would be better to just fix the injector first.

[dexetr30]

Could a bad CPS cause an injector to misfire and throw the P0202 code along with the code for the CPS?

[sharpxmen]

no, crank sensor problem should not trigger an injector code - the most likely problem is what Jeffy suggested as in the connector, if that's not it then it's the injector itself

you did keep the connector 1 to cyl 1, right? (do not swap connectors, the injectors are timed based on the intake valve opening)

changing the position for the injectors won't make it run better if the injector is at fault.

one test you can do - pull the plugs on the injectors 1 by 1 and see the one which has the least impact then that's the one with the problem, check the connector on that injector and even measure it with a multimeter (compare with the other ones, if it's bad would be easy to tell - if you get an injector code then it's an electrical problem something like an open circuit when activating the injector or no load on that circuit to be more specific, the PCM won't know if it's plugged - in this case you'd get a "too rich correction factor" code as in the O2 detected an extremely lean status).

[neale_rs]

The first code was for injector 1, then the code changed to injector 2.  Seems that injector is bad.

[sharpxmen]

The first code was for injector 1, then the code changed to injector 2.  Seems that injector is bad.

missed that [oops] then for sure that injector is the problem so scratch what i said about tesing it.