P0300 code after using Seafoam?

[thedern]

Hey all,

I posted about an engine tick a while back so I decided to try some Seafoam just to see if it would help. I ran it through the throttle body, let it sit, then started her up let it smoke, let it run then took it around the block. It has sat in the garage for a little over a week since this is just a weekend driver for me.

I took it out today and now I am throwing a p0300 code. The CEL flashes for a few seconds then stays on, steady. Idle is randomly rough but the tick sounds a bit better...

No engine lights or codes before the Seafoam treatment, it was just the last thing I did to the jeep so I am starting there with my research.

Could I have let the Seafoam sit too long? Perhaps not got it all out? I did not run the engine that long but I did hit some high rpms. My plugs were new, installed 2 weeks prior to seafoaming the engine.

Any ideas on what to do next?

 

[Chris]

My strong opinion on Seafoam is that it's nothing but snake oil in a can. However, my opinion aside, I suppose it could have done something like fouled your spark plugs.

If it were me, I'd go out and drive it for a little, clear the check engine code, and see if it goes away on it's own. That's where I would start at least.

 

[thedern]

Yeah, another rookie mistake on my end. The learning continues. All was well before I messed with it ( i am assuming cause and effect here )

 

[Boinked]

Seafoam does clean. It will break up the carbon buildup.
I have never put in directly into the throttle body. I have seen people do it on YouTube. Including mechanics.

With that all said. My thinking on it. "Maybe" it started to clean the gunk out of the throttle body and all that gunk went into your cylinder and fouled the plugs.

I have never liked the idea of cleaning a throttle body while the engine is running. The crap has to go through the engine. I prefer to remove it and clean it the old fashioned way. Takes longer and is probably just wasting my time. But it gives me the warm fuzzy feeling.

 

[thedern]

I will pull the plugs this weekend and check them... I hope it is that simple. The were new, but cheap fix if that is the issue

 

[Chris]

Just make sure you use the correct plugs!
What are the best spark plugs for my Jeep Wrangler TJ 4.0?

 

[cliffish]

I seafoamed through the intake and ran it in a tank full of gas...then I changed the plugs....had no issues but there sure was a good amount of carbon on my driveway by the tailpipe though.

 

[thedern]

Just make sure you use the correct plugs!
What are the best spark plugs for my Jeep Wrangler TJ 4.0?

I used that thread to buy install my last set

 

[Chris]

I used that thread to buy install my last set

Ahhh, well done in that case! Just making sure, since I know that often times people put the wrong plugs in and it ends up causing issues.

 

[TJ2]

I used Seafoam in my rigs, lucky no issue thereafter.
I abused my throttle at a ridiculously long-high RPM when I did mine, and so, maybe you did not flush it long enough.

 

[Fletcher34]

Seafoam should not have caused that code imo. I think it's probably coincidence. P0300 is multiple misfires detected if my memory serves me correctly. I few years back I got that code then as time went by, I'd get specific cylinder misfire codes. I replaced the ignition coil pack, plugs, did a full PCM reset and codes went away.

 

[Boinked]

Seafoam should not have caused that code imo. I think it's probably coincidence. P0300 is multiple misfires detected if my memory serves me correctly. I few years back I got that code then as time went by, I'd get specific cylinder misfire codes. I replaced the ignition coil pack, plugs, did a full PCM reset and codes went away.

Last time I got a p0300 i just reset the code. It never occurred again.

 

[thedern]

I replaced my plugs, cleared the code, and after driving for the last few days, the code has not returned. These are the plugs I pulled and were only a few hundred miles old when I seafoam'd the engine. Pretty blackened. So I cannot definitively say that fouled plugs were my issue as I did not try clearing the code alone, but these plugs look pretty rough.

Sent from my SM-G950U using Tapatalk