Hey Everyone,

Im having a strange issue with this engine and cant seem to figure it out, hopefully someone can point me in the right direction with it.

I have an 2005 2.7 v6 R Stratus that keeps throwing P0201 and P0202. The car shakes when you move it, the engine is rocking on idle, so its obvious cylinder 1 and 2 aren't either getting fuel properly. The issue started with just the P0201, but I found a bad diagram and replaced #2 by accident, now both are throwing the code, even after putting the original injector back into #2.

Here is what Ive done so far:

• Replaced both injector 1 and 2. Pretty simple job just time consuming, fire the puppy up, engine starts rocking after about a minute or two, same codes. So I checked the batch numbers for the injectors thinking maybe I got some lemons, replaced them with new ones, same thing.
• Checked the wiring harness all the way to the PCM, no breaks, cuts or signs of burning, melting etc.
• Replaced the upper intake bolts, all 7 and checked the threads on the lower intake, no stripping that I could see.
• Replaced coilpacks on the cylinders and also again but swapped with good ones from the other cylinders, same issue.
• Made sure I wasn't over tightening the upper intake and torqued to spec with an air wrench.
• Double checked fuel is getting to the injectors, no clogs in the line or pinches anywhere.
• Reset the PCM by pulling the fuse and holding the key forward for 3 chimes.
• Disconnected the negative for about 45 minutes, have done the positive yet as i need to take the driver front off to access it. + connection to the computer doesn't give enough room to take it off.

So I have taken this thing apart about 8 times so far and I'm stumped. I checked with the dealer to see if there was a PCM update, no dice there. Talked at length with a technician, he says its wiring but a PCM update wont do anything for me. Only thing I haven't done yet is move the injector over to another cylinder but that seems a moot point as I returned them for new ones.

Any help is appreciated. And yes, I am aware this engine has a weird history of issues among other owners. This one has been perfect for the last 2 years until now. Its a late 2005, so I might have just been lucky so far.

 

Did you start with the basics and make sure you have 12V at the injectors with the key in the RUN position? The PCM switches the negative side of the injector
battery(+12) -> fuse -> injector -> PCM -> battery(-)
Since they are opposite sides of the engine I would not suspect a problem with the +12V to the injector but it never hurts to check.
Generally spark related issues would give a misfire code whereas the P0201/P0202 are an electrical issue.
I'm not trying to talk down to you on the diagnosing but just want to make sure all the bases get covered.

 

Oh not at all, simple things are always usually overlooked. I checked the connection on injector 1 and 2, they have the proper voltage.

One thing I have been seeing a lot of on other forums is the code reporting incorrectly. For instance one guy had a P0201 but the issue was injector 5, that was with a newer car too. That issue actually seems to be common in Dodge across the board. Just weird issues I mean.

Thanks for the reply on this though. i will double check all the voltages tonight and see if anything is messed up again. I'm thinking of just replacing all the injectors this time or maybe the harness first.

Seems to be the goto, but what are the chances of a bad PCM/ ECM in this case?

 

It's not unheard of for PCM's to fail, but it's rare when some other issue (straight shorts in the PCM electrical being the most common) doesn't take them out.

I'd look at the ground side of the injector circuit to make sure that you don't have a short there. As TZMBird pointed out, injector pulse is modulated through the ground side of the circuit.

 

Sorry got real busy at work and couldn't reply back sooner. Looks like there is 12v all around. Which just makes this all the more puzzling.

 

So interestingly enough I decided to check the voltages and ohms again. Weird stuff here.

Injector 1: green wire was 11.46, yellow was 12.3
All other harness wires were 11.46 for both wires
Clipped the end off and the wire still showed the same
Checked the ohms on the injectors themselves, all fell steady at 12.3/4 except for injector 5 which showed at 11.82 and then jumped all around on me.

Swapped injector 5 with a new on, replaced the injector 1 end with a new one. Put it all back together and went to turn it over. Battery was dead. So got the v8 and jumped it , except now it wont turnover. Its definitely a fuel delivery issue.the car has a quarter tank. So I tested the fuel relay fuse while testing the voltages and ohms, maybe I zapped it. Ill get a new one tomorrow and see if it works. Also reset the PCM to be safe, no dice.

 

Well looks like another slew of issues have popped up. So I replaced the rest of the injectors. Now either the engine isn't getting fuel or spark. The engine will try to turn over but dies. I tried starter fluid, didn't start up.

Went ahead and replaced two coils that I wasn't getting any light on when testing them.
Turns out the battery went bad, so replaced that with a new one.

Now I didn't see a fuel pressure port under the hood, does this engine have one? Last thing I want to do is hook into the fuel line at the tank, but i might need to.

Any thoughts on the new slew of issues.

 

Well i got it running, looks like it was a blown fuse. a small 20 amp went out, replaced it and it fired right up. But still the same issue with the p0201/p0202 open circuit. So I took it apart again, sprayed WD40 on the connectors and retaped the wires, no dice. Idles rough and wont get over 2700 RPM when in park or drive gears.

Anyone have any thoughts of what it would be at this point?

Oh also replaced all spark plugs and coil packs.