My car still being on jacks, I decided to do some arbitrary cleaning of my engine bay. Seeing as my IM was already missing some bolts I had a go at the rest and took off the IM entirely. The inside was completely caked with black carbon shit, it looked like heart disease for a car.
I was so pissed off angry in the moment I didn't stop to take a picture, but I uploaded a photo that I found to be the closest to what it looked like inside my IM.

Anyone have a theory to why this buildup occurs and how to prevent it? Because I have never heard of or seen something like this is my life and I'm seriously hoping this wasn't due to neglect from the previous owner.

PIC FOR REFERENCE I'll upload my actual IM when I get some more free time again.

 

Who knows what kind of bad gas or crappy maintenance the last owner did. That is disgusting though..

 

If it really is as bad as that photo, I would say unlikely to be from bad gas...more like it was burning oil for a long period of time.

 

Tell us:

Do you run a stock or K&N type air filter?
What type of gasoline do you use? What brand and octane?
Do you use any gas additives?

 

^^^^^ In a non-DI engine, octane has no bearing on clean/dirty burning. All octanes of gas burn equally dirty. It's the additives used by the refiner/distributor that keep deposits down/to a minimum.

 

When I picked up the car a month ago, I checked the air filter and it was caked black and yellow. Probably from all the pollen out in Knoxville but it looked like it had never seen light in some years. I really wish I was exaggerating but it was pretty teribble. Here where I live I use Ethanol free 91 Octane. I've only had the car a month but I run sea foam about every 6 months. Picked up some BG44k for after when the car is running on 4 wheels again.

 

jeez! thrasher must have really thrashed that car. sorry bud

 

A few comments in no particular order:

• Grade or brand of fuel has no bearing on the crap in that manifold.
• An OEM style air filter, clean or dirty, will not cause the kind of buildup in that manifold.
• My best guess would be the engine has a lot of blowby and/or is burning lots of oil and what you're seeing is from the PCV and/or EGR systems.

Long story short, that ain't normal; I've pulled apart engines with over a half a million miles on them with intake manifolds which were far-FAR cleaner.

Edit: Looking again at the picture, I don't recognize the manifold; what kind of engine is it from?

 

my RL IM is no where look like that, if anything its just a light layer of carbon also noted the car has 120k miles and previous owner and I took great care of the car.

 

reverse google search shows it's a Lexus IS220 Diesel

 

I am still waiting for the actual pic from the OPs car to see how bad it really is.

 

Ahhhh, a Diesel, now it make more sense; why was that picture posted in this thread?

 

^^^^ it a new internet thing called "picture for attention" I just found this out recently too.

 

07 V6 Accord intake manifold after 10.5 years, I opened the whole thing up recently. Does yours look like this? How can you be pissed off? haha, it's normal.

You need to install an oil catch can to separate the oil from the air in the path of the PCV to get it cleaner. EGR valve is another contributing factor but blocking that off reportedly requires some ECU reprogramming because the ECU looks for electrical signal from the EGR valve. Be glad that the older J series does not use direct injection, that's why the valves look very clean because fuel sprays on top of the valves.

 

what brand catch can is that? i like the setup!

 

It's a Jegs air/oil separator.


I will be bypassing the EGR valve soon also. That's the other component that contributes to the dirty intake manifold.

 

after paying a shop to replace vc gaskets/tube seals & having a coil pack blow out (literally) a few months later then a friend/mechanic (big diesel) offered to replace my spark plugs which turned into tube seals also (said they were installed incorrectly) & then put it back together with same vc gaskets. After that the vehicle was puking all fluids. Major oil leaking (@ VC , oil pan/filter & under drivers side), PS fluid (had previous small leak) & brake fluid. So I figured I would do the vc gaskets/again myself (can't screw it up any worse than other 2 times..or so I thought) So while the IM was off I decided to clean it, however being sleep deprived I started cleaning without removing the TB, EGR & what I think is the IAC. So IDK how bad I've screwed up or what I should do next. I did immediately used some electronic contact cleaner to wash any carb cleaner that may have gotten into connectors. Any kind info to help this momo fix the F-up would be so appreciated!
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