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Discussion Starter · #21 ·
I am currently going to replace my brake booster check valve, clean the throttle body and the booster vacuum hose. How many vacuum lines are there? This is my first jeep. It's a daily driving project
 

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Discussion Starter · #22 ·
On a side note, I have to drop my tank again because the stupid airtex strainer fell off while replacing the malfunctioning sending unit
 

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You should have a diagram on the radiator core support or the firewall, identifying all the vacuum lines. Their are many.
 

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Discussion Starter · #27 ·
That helped thanks, I looked at it today and the vacuum line off the fuel pressure regulator is cracking, gonna try to find a new one
 

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Discussion Starter · #28 ·
I work at a dodge dealership and found that chrysler discontinued the vacuum line I need on the pressure regulator and also the brake booster vacuum hose. They have bulk hoses that should work.
 

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Discussion Starter · #30 ·
Yeah, but if you can find a solution to the problem, then it's a plus. I like to keep vehicle's on the road as long as possible
 

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I am very curios? On my son's XJ we had taken the dash apart and there is a box that is plugged into some wiring. It is to regulate the auto transmission. We drove it with it unplugged and it acted just like you describe. I wonder if that is where your problem might be? It might have gone bad? It is under the dash on the right side of the ash tray.
 

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Yup, I'm resurrecting this one.

I'm looking for opinions on where to look next to fix a (now only) a sputter at low idle. If I apply the skinny pedal while in gear it will non-violently chug until I get to ~1500rpm, and then whatever is off is not anymore and she drives like it did off of the dealership lot. I can drive all day if I want. I'm getting good mpgs (thanks regear!), and she has power to do whatever needs to be done. After driving for a bit, she idles just fine. It has proper throttle response, and purrs like a kitten. If I stop the engine for a little bit, it'll start right up but slowly make it's way back to the sputter. There are no CEL's being presented.

I had been thinking a Cam Position Sensor was the issue after replacing the a CKPS with a mopar CKPS. That made a world of difference in the symptoms I had been having and has me on the right track. When it sputters, she smells rich in the exhaust. No sulphur/bad eggs smell, just fuel. So I think the Catilytic Converter is okay. This symptom has me thinking it's a fuel delivery or spark issue. My ZJ does not have an EGR, and when my backup PCM is installed it has the same symptoms.

Today while troubleshooting the issue, I had replaced the cam position sensor, and the car will purr intitally but the PCM will adjust for the new part, and viola! the sputter is back.

I've replaced just about every sensor except the temp sender at the thermostat and the IAT(code scanner shows them working properly). New: IAC, TPS, MAP, CKPS, timing chain/gear set, wires, coil, distributor, cap, rotor, and they're about 3 months on new champions in the plug holes. The fuel pump, and filter/regulator is less than 1 yr old. I just put some fuel system cleaner in a 1/2 tank of gas today: we shall see what happens there.

So, I've been searching this forum and others, and have not found anything I have yet to think of.

After everything replaced thus far, I am gonna order a Mopar CPS, re-gap the plugs, and recheck for vacuum leaks.

I think that I have covered just about everything else. It seems as if the issue is fuel delivery or spark. The mechanical timing is spot on, and I am leaning towards a not up to spec CPS. Although I am less than 50/50 on that being the issue. I tried swapping out CPS' today while changing the plug wires. And though the idle was fine for the first couple of mins or so, the idle returned to the sputter.

Could this be a physical/mechanical issue? The sputter is intermittent, and then goes constant. It goes away after driving above 1500 rpms and the jeep runs pristine. The sputter will usually return on the next start.

Any ideas or suggestions?

If the next round of adjustments don't fix it, I will be at a loss for easy answers.
 

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I'm not sure what year zj you have? But my Xj had a stumbling issue a few years ago, it turn out to be inside the distributor cap, two of the contact points were completely gone. My rig was running on 4 cylinders.
 

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Yup, I'm resurrecting this one.

I'm looking for opinions on where to look next to fix a (now only) a sputter at low idle. If I apply the skinny pedal while in gear it will non-violently chug until I get to ~1500rpm, and then whatever is off is not anymore and she drives like it did off of the dealership lot. I can drive all day if I want. I'm getting good mpgs (thanks regear!), and she has power to do whatever needs to be done. After driving for a bit, she idles just fine. It has proper throttle response, and purrs like a kitten. If I stop the engine for a little bit, it'll start right up but slowly make it's way back to the sputter. There are no CEL's being presented.

I had been thinking a Cam Position Sensor was the issue after replacing the a CKPS with a mopar CKPS. That made a world of difference in the symptoms I had been having and has me on the right track. When it sputters, she smells rich in the exhaust. No sulphur/bad eggs smell, just fuel. So I think the Catilytic Converter is okay. This symptom has me thinking it's a fuel delivery or spark issue. My ZJ does not have an EGR, and when my backup PCM is installed it has the same symptoms.

Today while troubleshooting the issue, I had replaced the cam position sensor, and the car will purr intitally but the PCM will adjust for the new part, and viola! the sputter is back.

I've replaced just about every sensor except the temp sender at the thermostat and the IAT(code scanner shows them working properly). New: IAC, TPS, MAP, CKPS, timing chain/gear set, wires, coil, distributor, cap, rotor, and they're about 3 months on new champions in the plug holes. The fuel pump, and filter/regulator is less than 1 yr old. I just put some fuel system cleaner in a 1/2 tank of gas today: we shall see what happens there.

So, I've been searching this forum and others, and have not found anything I have yet to think of.

After everything replaced thus far, I am gonna order a Mopar CPS, re-gap the plugs, and recheck for vacuum leaks.

I think that I have covered just about everything else. It seems as if the issue is fuel delivery or spark. The mechanical timing is spot on, and I am leaning towards a not up to spec CPS. Although I am less than 50/50 on that being the issue. I tried swapping out CPS' today while changing the plug wires. And though the idle was fine for the first couple of mins or so, the idle returned to the sputter.

Could this be a physical/mechanical issue? The sputter is intermittent, and then goes constant. It goes away after driving above 1500 rpms and the jeep runs pristine. The sputter will usually return on the next start.

Any ideas or suggestions?

If the next round of adjustments don't fix it, I will be at a loss for easy answers.
Do you have ev1 or ev6 connectors for your fuel injectors? I had the ev1 for my xj and after building the stroker I had a misfire on 2 cylinders. Turns out the injector wasn't getting the signal on the offending cylinders. So I bought ev6 connectors since thats the style injector I had (they included and adapter) and I dont have misfires anymore.

It could be a bad/corroded contact causing the issue and perhaps it is finally able to make a stable connection. Maybe there's a corroded wire somewhere. I'd get some noid lights to check your injectors on a cold start.
 

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Do you have ev1 or ev6 connectors for your fuel injectors? I had the ev1 for my xj and after building the stroker I had a misfire on 2 cylinders. Turns out the injector wasn't getting the signal on the offending cylinders. So I bought ev6 connectors since thats the style injector I had (they included and adapter) and I dont have misfires anymore.

It could be a bad/corroded contact causing the issue and perhaps it is finally able to make a stable connection. Maybe there's a corroded wire somewhere. I'd get some noid lights to check your injectors on a cold start.
I am not getting any misfire codes, nor any injector codes. I am starting to suspect the injectors though.

I replaced the camshaft position sensor with Mopar today, and it didn't affect the sputtering issue. I also re-gapped the plugs. The plugs look new. although cylinder one has some discolorations on it, but all should be well there. New plugs, new CKPS, new wires, new coil, new cap n rotor.

When it sputters then moves over to borderline chugging, the exhaust smells rich.

I have a tank of gas to run through tomorrow that has a high concentration of fuel system cleaner in it: we'll see if that helps.

I am starting to think there could be an injector issue. I am gonna grab a compression testing gauge while near a harbor freight, and see what the numbers are. I fear I could have damaged a ring or two when the distributor went out and I had been engine braking for about a 1/4 to a 1/2 mile after the engine went dead.

If nothing is noticeably wrong with the compression, I have to start looking at the injectors. I swapped out engine harnesses and the problem is the same, so I am wondering if I have an injector going bad.

I'll update in a few days.
 

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229575


This is something I've never seen before, nor has my mechanic brother.

This set of plugs had less than 5000 miles on them. This was the worst, and the one in cyl no.2 was starting to do the same. I can only guess there was some sort of a manufacturing issue that caused too much resistance in the plug and the subsequent ~5000 miles made the spot grow and retain heart when driving the heep.

Now before you think user error, I'd like to think I am competent enough to install some spark plugs.

I was running with one dead cylinder (#1) and the 2nd cylinder was starting to go bad as well. As I was driving to get another set of plugs, the CEL light came on and was blinking. I pull over, and it would go out and leave no trouble code. It did this twice on the way to the parts store.

Hopefully this can serve as a lesson on about how to go with the cheapest items first while diagnosing engine issues.

I spent about $800 in sensors and other associated engine components to find the issue. These plugs were practically new, and I thought because that was so that they couldn't be the issue. I was wrong, and boy did I pay for it.

She's back to running like a champ, and I spent three days north of Pagosa Springs wheeling, and it felt good and I was relived this issue has been resolved.
 
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