Intermittent rough engine and misfires both in idle and while driving, codes p0305 and p0300

I circled where those 4-550 temperatures were coming from. temperatures all around and below that area was normal. That elbow further up the circled area in the picture is where it looked like the smoke was coming from

Hmm, very interesting. Can you see where it's coming from and going to?
Tom

It comes from this part here in the pic. I think this is the vapor canister purge solenoid from what I was able to see online. I apologize if I’m wrong. It located in this Jeep up front by the battery and there’s a couple of tubes running from it, including the one getting the high temps. It looks like it runs to the elbow and into the firewall (attached pic) not sure where it goes from there. I checked temperature through the rest of this line from start to finish and those 4-500 temperatures only came from that one section.

From what I’ve found, the EGR is also on this same side. Supposed to be on the back of the left cylinder head.

Is that the fuse box I see its attached to and the tubes are running by? In the first pic.

Yes. It just slides on and off. And thinking about it, I remember that part just laying on its side and I put it back on there.

Okay, so if its the tube that getting super hot then EGR has failed. Its a mechanical and electrical unit and when it starts to fail the gate sticks either open or closed. When this happens the car will start to through the codes that your seeing and run rough. That's the part in the picture. I think that's going to take care of the problem.
Tom

Everything I’m pulling up, that’s the purge valve pictured not the EGR. The EGR is supposed to be on the rear of the left cylinder head.

Would that cause the same issues? And would either throw injector codes?

The unit connected to the hot tube I believe is going to be the issue. I too will double check that part and the one your speaking of at the other location. I may be mistaken on its name. Can you make out the part number on it somewhere?

EVAP canister purge solenoid is what I’m finding for that part.

And this is what I’m finding as far as where the EGR is. It is in the general vicinity where smoke was coming from, just not sure if it was from there or not.

Good morning,

You are correct the picture is showing a purge valve and when it goes bad it throws a code for it most of the time. It's not the codes you are getting and its symptoms are not what you have, It's recirculating fuel vapor from the tank to the intake to burn off the fumes, it's an emission control component. The EGR failing has all the issues you are having both the running aspect and the code aspect. It sticking can explain the slight smoke you are getting as well. The EGR can be bad and not send a code for it too. Something is very odd having the tube from the purge valve being so hot and it has fuel vapor and plastic? The EGR is a recirculating operation which might be creating the other part to heat up. I suggest doing the EGR.
Tom

Morning. I will look into it, luckily the EGR is not expensive. Would the EGR be something that gets worse with more heat? As far as that tube, I’m only getting those temperature reading in that one section, nowhere else on that tube.

Good morning,

Yes it would get worse as the temperature increases like you have going on. It's very interesting that a plastic tube would read those numbers and it hasn't melted down.
Let us know how it works,
Tom

I find it interesting about the tube. Not sure if it’s a bad reading but I checked all around and even pointed the beam all over the place underneath it to see if it’s another part and it only went that high when the beam was directly on the tube in that one section.
Would the EGR cause the injector codes? Not doubting you at all, I know the EGR can cause misfires just trying to understand how that fits with the injector codes. Currently have p202 and p204 as well as p307.

Hi,

Seeing that the EGR is both an electrical and a mechanical unit on those vehicles, then yes. The electrical part is connected to the computer and if the computer is getting bad information strange things can happen. With having injectors codes with new injectors installed rules out the injectors especially with knowing that the engine isn't getting hot. We can also rule out a bad ground or bad wire/harness to the injectors because you running okay at cooler temperatures.

Has the p0202 and p0204 been coming and going, and the p0300 and p0305 gone leaving p0307? When you are pulling the codes has it been while the car is still hot and running bad or are these codes pulled when its cooler with the codes stored? What is the laser point temp at the EGR tubes coming from it when it's running badly? with all this we have gone through to get to where we are puts the ECU itself in question. That not being a cheap part, we need to know for sure first. Radiant heat warming up an ECU that's borderline beginning to fail could cause misguided codes. If its possible maybe try to out a piece of foam or sheet metal around or between the ECU and motor to insulate any radiate heat getting to it and see if there is a change in the time the engine starts to run badly. It's just a thought.

I believe some of this has been done but here is what they give us for an intermittent conditions its worth reviewing.

Diagnostic Test
1. INTERMITTENT CONDITION

NOTE: The conditions that set the DTC are not present at this time. The following list may help in identifying the intermittent condition.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

Refer to any Technical Service Bulletins (TSBs) that may apply.

Review the scan tool Freeze Frame information. If possible, try to duplicate the conditions under which the DTC set.

With the engine running at normal operating temperature, monitor the scan tool parameters related to the DTC while wiggling the wire harness. Look for parameter values to change and/or a DTC to set.

Turn the ignition off.

Visually inspect the related wire harness. Disconnect all the related harness connectors. Look for any chafed, pierced, pinched, partially broken wires and broken, bent, pushed out, or corroded terminals.

Perform a voltage drop test on the related circuits between the suspected inoperative component and the PCM.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Inspect and clean all PCM, engine, and chassis grounds that are related to the most current DTC.

If numerous trouble codes were set, use a wire schematic and look for any common ground or supply circuits.

For any Relay DTCs, actuate the Relay with the scan tool and wiggle the related wire harness to try to interrupt the actuation.

For intermittent Evaporative Emission trouble codes perform a visual and physical inspection of the related parts including hoses and the Fuel Filler cap.

For intermittent Misfire DTCs check for restrictions in the Intake and Exhaust system, proper installation of Sensors, vacuum leaks, and binding components that are run by the accessory drive belt.

Use the scan tool to perform a System Test if one applies to failing component.

A co-pilot, data recorder, and/or lab scope should be used to help diagnose intermittent conditions.

Before I start I do want to say thank you both, this has been a pain and hoping that get it right.
As for the codes, before the injectors were replaced I would say the issue was more frequent and it did not need to be as hot out for it to get pretty rough. After the changing them I’ve had some days where it’s not quite as hot out and have near perfect driving.
Before the injectors the main 2 CEL codes coming up were p300 and p305. I had p207 one time before I did the alternator and it never came back.
Currently after the injectors I have p204, p300 pretty consistent. Have seen them both stored and pending at same time. P307 started coming up approx a week later same as those(stored and pending). And yesterday driving on highway to swap cars with my buddy I had some pretty rough driving and the CEL even started flashing on me 3 separate times for a few seconds and stopping. When I got stopped is when I saw p202 was also pulled. So currently I have on the cel p204, p202, p305 and p307. Codes on both banks. The times I have had theCEL go off is if it’s been a few short drives or if I had a longer drive at night at cooler temps. My scanner does have a misfire counter in the test section and I have pulled it up before and it had misfires on every single cylinder.
As far as the EGR it’s located on the back of the left cylinder head and it’s very possible the smoke was coming from there since it’s that general area. Also as far as the wiring harness goes, it runs from the PCM on the passenger side to over the top on the cylinder heads.

Good morning,

With such random changes, inconsistencies with the codes with the parts that are now new. Besides the heat the ECU is the other commonality. A good visual inspection of the ecu's circuit board is in order. I'm uploading the jeep ECU showing the injector IC on the board notice the circled chip which is an example of a burnt chip. the 3 chips circled are the ones that run the injectors each chip runs two injectors. A cheap junkyard ECU may be in order.
Tom

Would that explain the smoke? If I got a PCM from junkyard it would need to be programmed right?

Well, I'm thinking the smoke is relates to the EGR. there is a distinct odor that would be associated with electronics burning up I think you would have mentioned it and yes a new PCM will need to be flashed by a dealer or a place with the special scan tool. That's why looking at the circuit board should be done and the EGR should be ruled out beforehand. If a chip has burned up you will see it. If this was the case I don't think it would run at all. If a junk yard PCM was installed I believe it would run and the issue would go away verifying that it is the problem then going though that expense would be justified. Then a new one could be flashed returning the proper mileage and so forth.
Tom

I have smelt a burning rubber type smell before, but that was before I did the alternator.
Just to clarify, are you saying that if a chip was burnt up that the Jeep wouldn’t run at all?

Well, depending on which one but pretty much yes. Some integrated circuit fail only when heated or cooled though. You can get whats called freez-it and it will instantly freeze whatever you spray it on to sub zero. If it was in my shop I would take the PCM cover off and shoot the chips with it with the car running if I didn't see any melting evidence. A partially failing chip will completely fail if frozen. If the EGR proves to be working properly or is replaced that is the next thing I would do. Here is a pic of what I'm talking about.

Okay. Have not had a chance to get the EGR yet, it’s in a crappy spot to get to and recruiting help. I did want to give and update as well, here the last couple of days it has started to stall on me a lot more. It has stalled in the past but rarely. It’s stalled on me several times last couple of days. Mainly while backing out of a spot, idling and it stalled on me at a stop light as well.
Also it’s looking more like the issues is mainly happening after start up. Last couple of trips (not as hot weather) it’s been fine most of the way to fist destination, especially when first getting going from overnight before engine reaches temp. Seems like the issue is happening mostly after coming to a stop and restarting within an hour or so or been running for a while and run into start and stop situations.
Last night after letting it sit for a few hours it was running great, ran into construction and had a big detour and lots of stopping and starting. It did fine for a while but after several stops the stutters started again and getting back on the highway was rough at first. Had to pull over cause the CEL was flashing. Stopped and restarted but it stalled on me before I could get going. After getting it going it seemed to get better as long as I didn’t push it too hard and got back home and it had stopped.
Similar today, made a quick trip, restarted after 15 minutes and it stalled on me 2 times backing out and once when putting it in drive. Had some hesitations to get going then it got better. Stalled on me at a light a little later.
Had some skips on the highway but not too bad again as long as I didn’t push too hard. After letting it sit for a few hours and driving back didn’t have any issues.
I also had code p1128 come up today as well. Closed loop fueling not achieved bank 1 upstream
Does this fit with an EGR issue?
Thanks in advance and sorry for the long post.

And almost forgot.
I will post the pic, while I was under the hood, I wiggled and pushed on what I think is the PCV while it was stuttering and it seemed to make it stop. Not sure if a coincidence but seemed to happen 3-4 times.

Hello,

It doesn't look like one if I'm seeing it correctly . If it had an effect then we need to look closer at it though. Does it have any vacuum lines or wires coning from it? If so, how many pins are in the wire connector for it. It looks like part of the evap system to me.
Let me know And I'll try to ID it.Look, for a part number on it.
Let me know.
Tom

Hey,

So from what I’ve pulled up in forums and online that is the crankcase vent to intake manifold tube. That rubber plug at the end is attached to the PCV valve. (It’s not on the oil filler tube on this model) That tube would be a vacuum line right?
Did you see my previous post about it stalling more and the p1128 code? I know it’s a long post, just trying to get you as much details as possible.

Good morning,

That code is interesting, its new to this issue isn't it? It sounds to me like the problem is getting worse and changing. Were you able to get your eyes on the PCM circuit board? I think you need to absolutely verify the PCM isn't slowly burning up. There are too many variables and changing codes and condition to point to a single sensor or component. I'm not sure if you can pull the PCM out and get a known good one to put in or somehow get the existing unit bench tested. At the least get the casing off and see if there's anything burnt. You would be looking for discoloration on the IC's (black rectangle chips) and puffed out capacitors, which are the small can looking things. This really is the next step.
Tom

It’s the first time seeing the code, it was pending. From what I’m seeing o2 sensors or the sensor heaters seem to be most frequent reason for that. I do remember Kenny mentioning the o2 sensors as well. I do have the o2 heater sensor test on my scanner. I’ve looked at it before but not sure what exactly that test does. I do remember looking at the test after driving for a bit and it was showing -40 degree. I’ll attach the pic I took. I think I’ve mentioned it on this thread before but not sure.

I went ahead and looked at the O2 sensor heater test as soon as I stopped after a good 25 minute drive. All of my sensors up and down stream and both banks showed min and max of -40 degrees and a test value of -40 as well. I pulled up pictures from July 4th where each sensor was a min of -40 and a max of 536 and each sensor had a different temp. B2s1 was at 113 that day and B1S1 was at 77.
Not sure if this means anything at all but thought it would be worth mentioning just in case.

Sorry to keep posting but think this may be important.
Just drove back, not much drivability issues just a couple little bumps and sputters. Had live data on my scanner and made sure it went into closed loop. Got back and parked and looked at the scanner and fuel system one was in open loop-fault.
Decided to go ahead and check the same O2 sensor heater test and this time they were showing readings. Min -40 Max 536 with a temp of 113 for b1s1 and 122 for b2s2.
I didn’t have an engine light on but went ahead and ran a scan and I had p0131 pending. O2 circuit low voltage b1s1
Can the sensors be causing all these issues?

Hi,

Well, if the O2's were messing up the code would be there. What about the PCM have you been able to look at its PCMs circuit board yet?

Is p0131 not an o2 code?

Yes, but it's telling you the mixture is not right not that the sensor is bad. meaning the computer isn't working right.

I’ll try and look in it ASAP. Honestly I’m a little nervous to mess with it.