P0130 - after replacing O2 sensors (1 Viewer)

[attaboy]

Have a p0130 CEL I’ve been chasing. I’ve replaced the exhaust manifolds and gaskets to get rid of a small exhaust leak, and both O2 sensors. p0130 and p0133 went away for a while, but p0130 has been coming back regularly now.

I was replacing the vacuum lines and noticed the EGR valve looks really bad.

I had replaced the melted EGR modulator when it had melted maybe a year ago, but figured the valve was fine bc I wasn’t getting the p0401 code.

From when the EGR modulator had melted.

I had replaced the cats and O2 sensors 2 years ago. I used denso sensors previously, this time used NTK since I read that’s what OEM was.

Also replacing the Carbon canister hoses since they’re in bad shape and considering changing the canister itself with a GM, based on another thread.

I’m planning to replace the EGR valve bc its clearly in bad shape. Is there something else I should be looking into?

 

[Malleus]

The EGR port in the upper intake is clogged with carbon. You can either spray many cans of brake cleaner in it (use the combustible version, not the tree hugger version) (pull the sensor and valve so you know the brake cleaner is getting the port open), pull the intake and clean the whole thing, or (what I do) ignore it.

 

[attaboy]

Ahh, you mean like from this thread?

1FZ-FE EGR

Hi - I removed the upper intake manifold from my '95 FZJ80 to sort out some evap system issues and clear my EGR passages. Everything is going OK (aside from most of the evap doodads being toast) EXCEPT: There is a vac hose from the EGR valve straight to a small steel tube sticking out of the...

forum.ih8mud.com

I noticed it didn’t look great after the EGR valve into the intake manifold.

 

[Malleus]

Well, I can't tell if you intended to point out the EGR sensor or the vacuum port, but yes, it's both that are clogged.

Although I don't think the clogged vacuum port will generate an ECU fault code. Clean both while you're at it. The vacuum port is a steel tube; you can't hurt it.

The best way to clean it yourself (most people have the machine shop "hot dip" the intakes, which I assume is an acid bath - my shop doesn't have such a tank, they have a commercial dishwasher for machine parts with aluminum friendly soap), is to use Carbon-Off. It's designed specifically to remove carbon (from restaurant griddles and such). I love it. You do have to remove your upper intake to use it, though, which is why I suggested brake cleaner. Normally I wouldn't come close to suggesting you flush crap you didn't want in your intake into your engine, but if your intake is clogged, so is the rest of the head, so I'd doubt it'll cause much of a problem.

If you use Carbon-Off, buy the smallest can you can get. It doesn't take much. You do not want to sniff that stuff, though.