Judging by the description provided, it seems you have a fuel issue. Since the issues started after doing engine work, specifically cleaning the injectors and replacing the o rings, I assume something went wrong there.

You changed a lot of parts and sensors at once, so it will make it a little trickier to uncover the root cause of the issues.

I see that the oil cooler sensors were OEM but were the replacement knock sensors OEM? Also beware of knock off parts. Buy from a trusted source.

Depending on how you cleaned the injectors, I think damage may have been done to them. Also, the o rings could be incorrect or improperly installed.

I recommend sorting out your fuel injectors and go from there. Make sure the o rings are the correct size and that none are torn, which could have occurred during the procedure. Then you want to check if the injectors actually work. Do they spray correctly, do they leak? I think both are occurring in your case, based on the lean and rich conditions. You intake gaskets may also need replacement.

 

Judging by the description provided, it seems you have a fuel issue. Since the issues started after doing engine work, specifically cleaning the injectors and replacing the o rings, I assume something went wrong there.

Depending on how you cleaned the injectors, I think damage may have been done to them. Also, the o rings could be incorrect or improperly installed.

I recommend sorting out your fuel injectors and go from there. Make sure the o rings are the correct size and that none are torn, which could have occurred during the procedure.

From post number 2. I knew it!

 

Thanks for the reply. I forgot to mention when it first failed to start I replaced the intake gaskets with felpro gaskets instead of the Dorman ones and did a smoke test for vacuum leaks and I couldn’t find one. The knock sensors, intake air and map sensors were from oreillys. And I don’t think I mentioned I replaced the spark plugs. I usually avoid doing so much at once but I figured since it was already going to be down for a while I’d make a project out of it and get the van ready for summer road trips. But I put Oring silicone lube on everything and cleaned all the electrical connections and added dielectric grease. Just took my time with it. I just hate to take it in for diagnosis and accept defeat. I cleaned the injectors with a little Amazon injector tester/ cleaner kit so I know all the solenoids were clicking at that point and I sprayed them out with carb cleaner while they were running. That’s what beats the heck out of me is when I was done it starts up fine and runs great for a few trips and didn’t start acting up until I was idling for about 20 minutes in line. So it probably ran good 50 miles. Well over an hour of runtime. When it first started idling rough it didn’t throw a code until the next day after it started struggling to cold start.
I guess I’ll start with an electrical check since I had a grand Cherokee with a battery issue where the battery checked fine but it was causing all sorts of random issues and a battery swap fixed it. Then I’ll start on rechecking the injectors. I don’t have a fuel pressure gauge and limited knowledge on injectors but too bad I decided to mess with them anyway.

 

The spark plugs are another thing that could be causing the misfires and rich/lean conditions.

What spark plugs did you use? Did you gap them to the OE recommended gap of 0.044"? Also they could have been damaged during installation if they were dropped into the spark plug tube. These are just some things to consider as potential issues.

Please tell me you still have the original knock, intake air, and MAP sensors. Not sure what brand of sensors you used from O'Reilly, but sensors are generally something to go OE for. If possible, put the original sensors back on, if they were working.

I recently saw a video from Eric the car guy about someone who changed a MAP sensor, in a Toyota I think, with a cheap aftermarket one. They also changed multiple parts at once but the problem still persisted. Turns out the original sensor was fine.

Your problems may have appeared after a while for various reasons. The stresses of driving and idling may have caused an o ring to fail, etc. Sometimes problems don't show up right away.

Good call on checking the electrical system. If all checks out, recheck your work and check for damaged components. YouTube may be helpful in diagnosing a bad fuel injector. Also, I would put the original sensors, named previously, back on the van.

 

I do have the original sensors. Ironically I swapped them out so I wouldn’t have to do the job 2 or 3 times like I am now. And I didn’t think to check the gap on the plugs but I didn’t drop any and I cleaned out the holes before I seated them in and did all the torque specs. I think they were auto lite iridium.
I’m a little rusty on auto mechanics but I’m catching up here lately. I did a decent bit of work to a carbureted 350 back a “few” years but cars have changed a little bit since then I guess

 

I'm the same way as you, I like to get things done together. However, I have started telling myself if it isn't broken, don't fix it. Everyone's heard the saying but it's difficult to follow, for me atleast.

Not sure how great I feel about autolite. I've heard negative things about them from some people but the reviews seem ok. So not sure.

I would try installing the old plugs. If that doesn't fix the problem, start looking into injectors. What did you clean them with?

Also, make sure all electrical connectors are fully seated. That's probably the easiest to check before spark plugs, and then injectors.

 

Ok I had some free time to fiddle with it today and I can get it to start if I cycle the key to let the fuel pump run then pull the fuel pump fuses (m37 and m25) then crank again, it will fire right up and run smooth for a few seconds before it dies. I’m not sure what that would mean but it will crank like crazy and not start if the fuel pump fuses are in.

I’m pretty confident in the battery and terminals at this point since I know it will still crank and start/run smooth.

Cleaned injectors with carb cleaner spray while I was testing them with an Amazon tester thing.

 

This kind of sounds like a failed fuel pump relay, the one that's inside of the TIPM, but you already installed the bypass. That didn't fix it, so we have to keep digging.

If you prime the fuel pump then pull the fuse (removing power to the pump), the residual fuel pressure can keep the engine running for a few seconds, as you've experienced. Does the engine run smoothly for a few seconds even if you don't pull the fuse?

Because I can't wrap my head around why the engine would run smoothly without the fuel pump fuse. I think it's just a coincidence.

The engine is misfiring. It needs spark, fuel, air, and compression to run. I highly doubt that compression and air are the problem. I'm really leaning towards damaged or improperly installed injectors or a damaged fuel rail (it's plastic).

That's about all I can think of.

There's a very knowledgeable member on here @Sienile who should be able to offer more guidance. But I haven't seen him post in a few days. Good luck

 

I pulled 3 the plugs back out just now and they are black and maybe not completely fouled out and 2 of the 3 were wet and smelled like fuel. I also noticed they are about 1 mm shorter than the champion plugs that were in it. So thats the first thing to swap back out. I also pressurized the fuel system with the injectors still in and there were no leaks. Everything looks good to my amateur eyes so I’ll swap plugs and update again later.
There was also enough oil in the upper intake for it to drip out of the throttle body when I had it laying out of the vehicle. Maybe just from running rough?

 

The replacement spark plugs could certainly be your problem. What was the part number?

Also, some oil mist in the upper intake is normal. I have never seen there be so much oil that it comes pht by the throttle body. Your PCV valve is likely shot. Clean the throttle body well. If it's covered in oil, no wonder it can't get the air fuel ratio correct.

 

Autolite xp5701 are about 1mm shorter than the stock champions. My dad still thinks there is a bad sensor causing it to run rich. But I’m sure the plugs and the copious amount of dielectric grease inside the plug boots didn’t help it either.

 

I think I just figured it out. The set of fuel injector o rings I got were wrong. Injectors just slide right out of intake too easy. There’s a larger size o ring on the bottom of the injector and the kit I got seemed to be all the same size. Here is a link to the set I got which is incorrect and there is a review left from someone saying they got them for a 2014 wrangler and it wasn’t the correct size for the bottom of the injector going into the intake but they only fit the top. I’ll go to the dealer tomorrow and get the correct orings. There’s my vacuum leak although it wasn’t bad enough to leak on my smoke tester at 1 psi. I’ll update after I get it back together but I bet this is it.

Not sure if I can post a link but I’ll attempt:
This one DO NOT GET! https://a.co/d/hXP3TPQ

 

Same part number on Napa shows o rings with 2 different colors for the different sizes. Part number is Felpro es73046 but I’ll wait and get the dealer part so I can get it done right.

 

I just got the orings from the dealer. I tried ordering the correct felpro es73046 from Napa and it still came with all 12 upper orings instead of 6 of each size. So I went to the dealer and ordered the oem mopars. A bit pricey at $34.80 but I went with it. Then I found out that’s for one injector. So if anyone wants to follow me down this road of cleaning injectors and getting new orings as maintenance the final price was $222.89. Only 10x the price of the felpro rings that don’t fit. I’m hoping this solves the issue. I will update but I won’t have time to work on it for a few more days at least.

 

Ouch! That’s a highway robbery, but when you have no choice, you have to pay up.

That’s why I stick to the tried and true mantra If it ain’t broke don’t fix it. Certain things are better left alone if they work properly.

 

I installed the new oem orings and plugs and it started and ran fine for a minute then got rough so I let it idle while I looked through the obd2 scanner. At at one point I noticed the bank 2 sensor 1 output voltage went down to zero when it was previously at 0.8v . I was also getting the codes u1110, u1120. I’m thinking it’s something electrical. I guess I’m hoping it is electrical. I cleaned the connection to the b2s1 o2 sensor but no change. Could also be a vacuum leak. I thought I could hear a little bit of sucking but I’m getting delirious now. Also when I shut it off it sound like the pressurized sound after a vehicle diesels at shut off. It didn’t diesel but just had that huffing sound as it was shutting down. So could be anything. After I shut it off and it cooled down it wouldn’t start again. I’ve put enough spare time and money in it so I’ll send it to the shop and let them put a better computer and mechanic on it.

 

Getting someone else to look at it was a smart move. Make sure to let us know what the problem was once you find out!

 

According to what I can find with those codes, it's a dying battery causing the ABS computer to glitch out. I'm guessing when it freaks out it spams the CAN and that overwhelms the PCM. This is oddly common across many Chrysler products over the last 20 years. Just search for "u1110" and look at all the results.

 

I’ll check it out but it has a 2 year old die hard platinum agm battery and I doubt they will swap if it checks good. It’s reading 12.3v after sitting several days with temps in the 20s at night. I did replace the negative terminal but there was no change and at this point it will crank but won’t start even if I clear codes and touch the terminals together to reset the computer.

 

I was thinking I did have an old 98 grand Cherokee that did similar stuff until I replaced the battery. But it had some extra wiring for an alarm system that was not installed when I got it so I assumed most of it was due to the bad alarm job. It did eventually need an ecm. It got where it would stall out and I’d just wiggle the ecm connections and it would run fine for a while.

I wish I had a battery I could swap with it just to check if it changes anything but it is the newest battery we have. I think the Miata has top post but it’s a tiny battery…

 

Got jumper cables? Have the other car running for a bit before starting the van. And double check your terminal connections.

 

12.3V resting voltage is low. AGM likes to be close to be at 12.7 and above. You need to charge it or put it on a booster.

 

So here it is guys. They couldn’t find any faults with electronics so they wanted to check the fuel rail and the work I did to it. They replaced the lower intake stating there was some cracking near the bolt holes. Then it was still not right so they replaced an O2 sensor and now it’s fixed. They told me it was definitely a vacuum leak that caused the O2 to foul out because the O2 alone couldn’t cause it to run as rich as it was. I’m just a little suspicious because they usually call before replacing anything but there was a couple days of no calls after they said they were doing the intake so it made me think that wasn’t it. Then when they did finally call he said it’s fixed but they had to replace one O2 sensor to make it just right. So I’m thinking yea there was probably no change after the intake was installed.
There’s no way to know for sure (with my limited knowledge) if it needed the intake or not but it’s fixed so at least the bloodbath is over.
I feel strongly that the orings were a problem so I’m glad I got the oem ones installed. And I feel like the intake isn’t a bad idea even if it wasn’t gone yet. We use this van for road trips and the pain of breakdowns are magnified while riding 4 kids deep. Luckily we’ve had this beast for 7 mostly trouble free years so I can’t complain too much even though the amount of plastic on the motor is disappointing and the price of oem plastic and rubber is offensive. Now I just need to finish the parking brake cable, serpentine belt and dvd player screen and we are ready for summer… hopefully

 

They likely cracked the intake themselves and blamed you for it. A vacuum leak will cause a lean running condition, not rich.

 

They said it was extremely lean on one bank and extremely rich on the other. My first thought at that point was an O2 sensor but they wanted to dig down to the fuel rail & lower intake likely to recheck my work but they said they needed to inspect it for problems on the fuel delivery. So there’s a decent chance they wanted to find a problem to justify the extra labor and time plus recoup some of the diagnostic time they were racking up while checking to see what I messed up.

They did show me the lower intake. But it’s a decent sized shop so they do 100 oil coolers a month. There’s no guarantee you’re looking at your own parts. But either way The cracks they showed me were on the webbing between the bolt holes and the main housing so it’s unlikely there was a problem. Not to mention I don’t remember it looking like that when I had it out. But I’ll never know. This is the “best” shop in town at the moment. I’m waiting for a smaller one to open so I can have a place where I can talk to the actual mechanic rather than the computer tech. This was like talking to a brick wall. He said there was a sensor on the fuel rail which there’s not. He said 5 of 6 bolt holes had cracks. There are 8. He said the new intake came with a new foam pad. It probably doesn’t and it’s not installed. I just avoid any shop like the plague unless I know exactly what I want done and the cost up front. I’m the one that has to sit on the side of the road with 4 kids, not them.

 

I also wanted to thank everyone for the help. I really appreciate it. I needed some guidance on this one for sure. I’m still learning all the sensors and Chrysler electronics. Most of my mechanic experience is going into power wheels and Rc trucks lately.