Running rough

[Braden04]

2013 ram 1500 5.7, my truck seems to run like crap only when it rains. Drives fine at first then surges and bucks every minute or so. If I hit that gas while it’s doing that it’ll clear up a little. When I come to a stop it occasionally dies. Starts right back up. Idles rough. I originally thought it had something to do with water getting in CAI. I bought an in closed one and it’s still doing it. Bad gas was an option but after I park it and let it sit overnight after the rain passes it runs like a top. Of course until it rains again. If it’s barely misting I don’t have a problem. Hope someone can help.

 

[Jeepwalker]

It's probably a flaky humidity sensor. (just kidding)

I'd start with checking for any engine codes first. You never know, the temp sensor could be on the edge. Ideally, if you had a scan too like THIS, you could observe readings when it was stumbling. It could well be cracked ignition coils, or something like that which spark errantly when humid.

But first, I would push down all the fuses and wiggle the relay, cause it costs nothing and takes a minute. Sometimes they work themselves up. Then I'd wiggle the bundle of wires beneath the fusebox. Just wiggle them gently...in case there IS a weak connection.

Then, I'd make sure the battery cable connections, and grounds are good. Esp the grounds...at the body/frame/engine. Grounds are a common source of issues.

Now we're getting to the real stuff (but don't overllook the common small things).
1) Remove the air intake snorkle tube, open the throttle body butterfly valve and inspect for any carbon/fuel deposits. If there are ANY....clean with some throttle body cleaner and a solvent-safe angle brush (like a big tooth brush) that you can get at the auto part's store for like a buck. Never use anything abrasive. A little deposits around the bore or on/behind the throttle body blade can cause stumbling. Be sure when you put the snorkel tube back on it's on 100% proper....not folded under (by mistake) back by the clamp.

2) While the snorkel is off, look over for any cracked hoses, or hoses which may have fallen off. Be REAL thorough in your looking. totally conceivable on a '13 a hose could be cracked and sucking air when it shouldn't.

3) If you don't have a scanner (and even if you do), remove the igition coil connectors and ohm them out. See if any are quite a ways off from the others. Ideally you would remove each coil and inspect it's end for micro-cracks and gray electrical traces of sparking ...to the head. Thats pretty common and it only takes one. Watch some videos on coils what to look for. When it's real humid it's easier for arcs to jump...

 

[Braden04]

It's probably a flaky humidity sensor. (just kidding)

I'd start with checking for any engine codes first. You never know, the temp sensor could be on the edge. Ideally, if you had a scan too like THIS, you could observe readings when it was stumbling. It could well be cracked ignition coils, or something like that which spark errantly when humid.

But first, I would push down all the fuses and wiggle the relay, cause it costs nothing and takes a minute. Sometimes they work themselves up. Then I'd wiggle the bundle of wires beneath the fusebox. Just wiggle them gently...in case there IS a weak connection.

Then, I'd make sure the battery cable connections, and grounds are good. Esp the grounds...at the body/frame/engine. Grounds are a common source of issues.

Now we're getting to the real stuff (but don't overllook the common small things).
1) Remove the air intake snorkle tube, open the throttle body butterfly valve and inspect for any carbon/fuel deposits. If there are ANY....clean with some throttle body cleaner and a solvent-safe angle brush (like a big tooth brush) that you can get at the auto part's store for like a buck. Never use anything abrasive. A little deposits around the bore or on/behind the throttle body blade can cause stumbling. Be sure when you put the snorkel tube back on it's on 100% proper....not folded under (by mistake) back by the clamp.

2) While the snorkel is off, look over for any cracked hoses, or hoses which may have fallen off. Be REAL thorough in your looking. totally conceivable on a '13 a hose could be cracked and sucking air when it shouldn't.

3) If you don't have a scanner (and even if you do), remove the igition coil connectors and ohm them out. See if any are quite a ways off from the others. Ideally you would remove each coil and inspect it's end for micro-cracks and gray electrical traces of sparking ...to the head. Thats pretty common and it only takes one. Watch some videos on coils what to look for. When it's real humid it's easier for arcs to jump...

Throttle body is brand new,(I’m not saying it couldn’t still be an issue). I just got all new coil packs today, going to put them on later. I changed all spark plugs about a month ago. I didn’t think to look at the ends of the coil pack. Temp sensor is a couple months old. I have a couple codes that stay, one to do with coolant temp (saying it doesn’t get up to operating temp quick enough). Another for o2 sensor (I have cam,LT catless headers). When it did it the last time I plugged it up and didn’t notice any new codes. I’ll try what you suggested, thank you for your input

 

[Jeepwalker]

Well there's (likely) your problem right there....coolant temp. If it's off (and parts store parts suck these days!), it might be telling the tk to do things or give fuel/air that isn't right for the conditions.

Do you have a scan tool where you can look at the temp (cold), then hot? You actually don't need a scan tool. Just take your multimeter, or get a $5 one from harbor freight, remove the wire clip and ohm-out the contacts direct at the temp sensor when the truck is cold (in the morning), and then repeat when it's fully warmed up. If you bought a parts store temp sensor it could well be flaky. Or a wire could be pinched, etc. Compare your cold/hot readings to a temp/ohm scale. But a scan tool tells if and what the computer is seeing. If it's getting a good signal, the wiring is probably good. (note: Im not 100% sure that is the right resistance/coolant scale...do a search. But it gives you an idea).

You might draw out or pour some fuel into a glass jar to make sure there still isn't any water in it. That can be a tricky one to analyze and it befuddles a lot of mechanics b/c you can't see the fuel w/o actually looking at it. Or run a couple containers of fuel water treatment in it. When a person has real water in the fuel it takes a couple tanks of fuel (sometimes several) and treatment to work the water out.

 

[Jeepwalker]

Just b/c the throttle body is new...maybe the gasket is bad. Or a hose got broken upon installation. There could be a lot of things.

You did a good job with the plugs and stuff. You'll probably have to start with basic troubleshooting. What's the fuel pressure, What's the vacuum, Are all the electrical connections good? Is the CTS where it should be at?

Rule out the CTS as of now.

 

[Braden04]

Just b/c the throttle body is new...maybe the gasket is bad. Or a hose got broken upon installation. There could be a lot of things.

You did a good job with the plugs and stuff. You'll probably have to start with basic troubleshooting. What's the fuel pressure, What's the vacuum, Are all the electrical connections good? Is the CTS where it should be at?

Rule out the CTS as of now

Just b/c the throttle body is new...maybe the gasket is bad. Or a hose got broken upon installation. There could be a lot of things.

You did a good job with the plugs and stuff. You'll probably have to start with basic troubleshooting. What's the fuel pressure, What's the vacuum, Are all the electrical connections good? Is the CTS where it should be at?

Rule out the CTS as of now.

thanks once again, especially for not being an a$$hole. I’m no master mechanic so I got questions sometimes. Alot of the times I get $hit on lol. I’ll go over the things you suggested.

 

[Braden04]

Well there's (likely) your problem right there....coolant temp. If it's off (and parts store parts suck these days!), it might be telling the tk to do things or give fuel/air that isn't right for the conditions.

Would that make a difference or not if it was raining vs dry outside? Could be a dumb question but it seems that if that were the case then it would be like that all the time. Not just when it’s raining..?

 

[Jeepwalker]

IDK...it could be. On these tricky problems, you have to bat down the problems one at a time. So if there's a code, definitely worth checking out what it is. It doesn't take much to ohm it out and check the ohm coolant table. There might be two temps...I can't remember...one might just be for ambient outside air temp. Verify which one the truck is saying is sending the code.

I was going to say O2 sensor too...but you said you changed it. Did you use all Mopar parts..just curious?

 

[Atcer2018]

After reading your initial post several times I’d recommend going back to your initial thought of the CAI. All of the suggestions Jeep gave are very valid and should be considered but the thing that sticks with me is your statement that on initial start it runs fine for a while then deteriorates. The hood of the truck protects from rain falling from the sky so it’s not like water is pouring over the engine. Rain brings higher humidity and that humidity would affect the sensors and coils regardless of when it’s started. If it starts and runs fine for a period of time then deteriorates it sure sounds like it’s pulling moisture somehow. Any way you can put the original airbox and snorkel back in to confirm the CAI isn’t the issue?

 

[Braden04]

After reading your initial post several times I’d recommend going back to your initial thought of the CAI. All of the suggestions Jeep gave are very valid and should be considered but the thing that sticks with me is your statement that on initial start it runs fine for a while then deteriorates. The hood of the truck protects from rain falling from the sky so it’s not like water is pouring over the engine. Rain brings higher humidity and that humidity would affect the sensors and coils regardless of when it’s started. If it starts and runs fine for a period of time then deteriorates it sure sounds like it’s pulling moisture somehow. Any way you can put the original airbox and snorkel back in to confirm the CAI isn’t the issue?

That’s a great idea, I just don’t have the OG airbox anymore. The one that first gave me problems was a K&n so I went to S&B. I also drove it with the k&n for at least 4-5 months before this issue came about.

 

[Braden04]

IDK...it could be. On these tricky problems, you have to bat down the problems one at a time. So if there's a code, definitely worth checking out what it is. It doesn't take much to ohm it out and check the ohm coolant table. There might be two temps...I can't remember...one might just be for ambient outside air temp. Verify which one the truck is saying is sending the code.

I was going to say O2 sensor too...but you said you changed it. Did you use all Mopar parts..just curious?

My truck had lifter problems, sent it to a place that did the cam,lifters,pushrods,springs, timing chain, & LT headers. I cannot confirm that he used mopar brand O2 sensor. I’m sure when I get home from work I can look. Idk if itll say something verifying that on the O2 sensor. I would imagine it would though.

 

[Sherman Bird]

Go to an Auto Zone or O'Reilly's and get it scanned for trouble codes.
Kindly share those with us! Thanks!

 

[Braden04]

Will do, thank you sir

 

[Atcer2018]

That’s a great idea, I just don’t have the OG airbox anymore. The one that first gave me problems was a K&n so I went to S&B. I also drove it with the k&n for at least 4-5 months before this issue came about.

Is the S&B an oiled element like the K&N? I’ve read numerous posts about how the oiled elements can coat the MAF with a slick coating. I don’t have personal experience with them but evidently it’s a thing. It still doesn’t explain what it runs fine at first then gets worse only when it’s raining. I’m assuming in Louisiana y’all have a pretty wet spring season.

 

[Braden04]

Is the S&B an oiled element like the K&N? I’ve read numerous posts about how the oiled elements can coat the MAF with a slick coating. I don’t have personal experience with them but evidently it’s a thing. It still doesn’t explain what it runs fine at first then gets worse only when it’s raining. I’m assuming in Louisiana y’all have a pretty wet spring season.

Yeah it’s pretty $hitty weather 50% of the time. Also yes it is oiled.

 

[Braden04]

Yeah it’s pretty $hitty weather 50% of the time. Also yes it is oiled.

Is the S&B an oiled element like the K&N? I’ve read numerous posts about how the oiled elements can coat the MAF with a slick coating. I don’t have personal experience with them but evidently it’s a thing. It still doesn’t explain what it runs fine at first then gets worse only when it’s raining. I’m assuming in Louisiana y’all have a pretty wet spring season.

another thing to note is the s&b routes to the fender right by the headlight. I guess there is a possibility of once I start actually driving it’s sucking rain/moisture in.

 

[Jeepwalker]

Hemi = MAP sensor...

(great point though for other vehicles)

 

[ToxicFire]

I had a similar issue on my wifes escape and it ended up being the coil packs getting moisture in them somehow.
Everytime it rained we would have the issue and the dealer couldnt figure it our nor the local shop so we took it to another shop and they noticed moisture and put dielectric grease everywhere on the boots and then boom no more issues when it rained. We ended up just buying new packs and it was all good. Until we sold it to get a jeep haha

 

[Jeepwalker]

Coil packs can act flaky when they get warm. With a SCAN TOOL you'd be able to watch misfire counts..probably zero in on a particular coil. IF that was the problem.

 

[Braden04]

I had a similar issue on my wifes escape and it ended up being the coil packs getting moisture in them somehow.
Everytime it rained we would have the issue and the dealer couldnt figure it our nor the local shop so we took it to another shop and they noticed moisture and put dielectric grease everywhere on the boots and then boom no more issues when it rained. We ended up just buying new packs and it was all good. Until we sold it to get a jeep haha

I’m going to replace them this evening hopefully that’ll do the trick