Oil on spark plugs - misfiring p0300

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Rocket Man

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I had a lot of misfires and stuttering on hard acceleration and it got worse and worse. It was plugged cats, the engine couldn’t breathe so it was coughing and choking. It got worse over time, and was worse when it was hot. Once the exhaust cooled it would be fine until it warmed up. Just another possibility.
 
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I had a lot of misfires and stuttering on hard acceleration and it got worse and worse. It was plugged cats, the engine couldn’t breathe so it was coughing and choking. It got worse over time, and was worse when it was hot. Once the exhaust cooled it would be fine until it warmed up. Just another possibility.
I will add this to the list to evaluate however I can.

These are all free checkups and definitely open my eyes for future possibilities on my other vehicle (09 4cyl Camry).
 

Rocket Man

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I will add this to the list to evaluate however I can.

These are all free checkups and definitely open my eyes for future possibilities on my other vehicle (09 4cyl Camry).
I had a shop do a flow test on the cats, it didn’t cost much. There are other ways I’ve heard of.
 

Larryjb

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I can't recall, did you replace the intake manifold gasket? If you have air leaks into specific cylinders, unmetered air can enter those cylinders and cause a misfire.

When I had my misfires, I found it was very hard to diagnose conclusively, other than random misfires on one bank only. I may have also had a lean code.

Others say you can flow propane around the intake. I had tried that, but I couldn't get any results from that test. I think some one here did a smoke test. That might work better, but you'd have to have a way to see "under" the intake as well which is tough to do.
 

Larryjb

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Check post #12 here:

I didn't have a lean code in the beginning. It was the lean code that led me to change the IM gasket.
 
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I’ll have a go to look at that.

I just check my transmission fluid - not good. It’s dark and low. I’ll be doing a transmission fluid change as soon as I can.
 

strutaeng

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I’ve seen mention of a specific tool for these rigs - do you have a suggestion?

I agree with you 100% - before I became engulfed in this process I spent $100 on blue driver scan tool - it has the ability to see misfires on each cylinder but it’s not live.

I’m trying to do what I can without spending a ton of money on “fixes” that aren’t fixes.

I’m sure y’all have been here before - 3 kids in private school, Mtg, extra curricular, etc. just not a lot of expendable cash.

This forum has been helpful, I’ve learned a ton about the engine and engines in general - for that I am grateful.

Thanks for continued support and brainstorming to help a new wrench turner along.
Understand completely. Yes, same situation here.

I've had the higher end handheld Innova from AAP and it's decent, but kinda of expensive for what you get. It does do the injector balance test and has live data, but not cylinder misfire count.

I tune in to Pine Hollow Diagnostics and he recommended this Topdon dongle. I ordered it and just received it in the mail and was messing with it. It has a lot of features. I didn't see an injector balance test though, but does have cylinder misfire count and a lot of other bi-directional controls. The only drawback is after the first year they charge you like a $60 subscription per year. Still doesn't seem too bad if you are a DIYer.
TOPDON TopScan OBD2 Scanner Bluetooth, Wireless OBDII All System Diagnostic Tool for iOS & Android, Bidirectional Scan, Check Engine Car Code Reader, Vehicle Performance Test, Repair Guides, AutoVin https://a.co/d/hiNlqVM

Another option is the Tech2 clone. That one should do all the functions and covers up to like 2013 models IIRC.
 

Rocket Man

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A lot of us here have a Tech 2 clone, in fact there’s a list of members available to help using their tech 2 by area.

 
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Understand completely. Yes, same situation here.

I've had the higher end handheld Innova from AAP and it's decent, but kinda of expensive for what you get. It does do the injector balance test and has live data, but not cylinder misfire count.

I tune in to Pine Hollow Diagnostics and he recommended this Topdon dongle. I ordered it and just received it in the mail and was messing with it. It has a lot of features. I didn't see an injector balance test though, but does have cylinder misfire count and a lot of other bi-directional controls. The only drawback is after the first year they charge you like a $60 subscription per year. Still doesn't seem too bad if you are a DIYer.
TOPDON TopScan OBD2 Scanner Bluetooth, Wireless OBDII All System Diagnostic Tool for iOS & Android, Bidirectional Scan, Check Engine Car Code Reader, Vehicle Performance Test, Repair Guides, AutoVin https://a.co/d/hiNlqVM

Another option is the Tech2 clone. That one should do all the functions and covers up to like 2013 models IIRC.
Is there a specific brand or website I should look to purchase a Tech II GM scan too from?
 
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A lot of us here have a Tech 2 clone, in fact there’s a list of members available to help using their tech 2 by area.

I want to get one of these Tech2 clones - it is in fact Christmas season and it maybe the perfect “Christmas wish list” item to give my Wife for ideas this year.

I am just not finding a viable website/vendor to purchase from.

Any ideas?

Sounds corny, but this may work out for Christmas hahaha
 

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