Engine Lights came out

How many miles on it? Could be lots of things mileage related.

 

What car?

What age?

Start by cleaning the maf sensor

 

is it something you can detect while driving, or just the codes?

 

Have you cleaned the maf sensor yet?

 

good idea see the nutzaboutbolts video and do the whole circuit

 

It isn’t that bad.

Where in California are you located?

If you only do one, you haven’t gotten the whole circuit and the problem remains.

Good luck and keep us posted .

 

If you need Techstream to read any codes, @gta_ is local to you and has a copy.

Any questions as you progress through the job, keep us posted .

 

It looks intimidating but it’s not that bad once the lower rear nut is off the EGR cooler. You should give it a go, the life of your head gasket/engine could very well depend on it.

 

The EGR cooler and valve are really one item, comes out together. Read this thread all the way through:

EGR & Intake Manifold Clean Results | PriusChat

A couple of points regarding coolant:

1. You do not need to disconnect any coolant lines to do the intake manifold. You can remove the throttle body with hoses attached, and just tie it off to the side.

2. With the EGR valve/cooler removal: if you drain a couple of quarts from the radiator into a clean container, the coolant level drops completely below the egr valve/cooler (apart from a little, trapped at back corner of cooler, which you can carefully tip out, and to your previous drain). When everything is reasembled, pour the drained coolant back into the reservoir. The level will be a little high, but will settle with a drive or two.

How badly clogged was that pipe? That'll give you clue as to what the rest of EGR system condition.

Also, thoroughly clean the intake manifold, especially the little EGR tubes, one per port.

And, watch all the relevant @NutzAboutBolts videos. There's a thread pinned at top of 3rd gen maintenance forum, with all the videos.

Does the engine coolant level hold pretty steady. If it's always dropping, could be head gasket failing. Leak down test would help diagnose.

 

It could be some clogged fuel injectors, try putting some heavy duty fuel injector cleaner in the gas tank. Misfires can be caused in two ways, lack of spark and lack of fuel. It sounds like you addressed the spark problem.