Egr line replacement

[rabbhill]

I had my exhaust manifold gasket replaced to fix an exhaust leak on Tuesday. It was supposed to be a simple job, or so the mechanic said, don't in 3 hours, no problem he said. It took all day Tuesday and most of Wednesday. When I got my truck back, he said everything was fine. I drove to work, on the way my check engine light came on and noticed a drip so I opened the hood. My master cylinder reservoir has a huge melted hole in it. I called the shop and they said "we broke your egr line so we welded it back together!" WTF So I thought about taking Hal back and making them fix the damage, but I paid them to fix him the first time and they screwed up bad so I'm not inclined to let them go back and work on him for free and break him worse. The CEL is always off when I first start Hal, but when I start driving it comes back on with in 2/10th of a mile. What I need to know is: could the check engine light be from them clogging the egr line when they welded it back together and how hard is it to replace the master cylinder reservoir and how hard is it to replace the egr line. I googled it and checked YouTube but couldn't find anything concrete.
Thanks!
Hals specs:
1994 Explorer XLT 4.0 4x4 lifted but still mostly stock.:exporange

 

[FR-425]

Changing the master reservoir is no biggie.

They probably broke (CUT) the EGR tube where it connects to the manifold (very rusty) PITA to get off without breaking it. (common practice) welding should not cause an issue. However is may have contaminated the DPFE sensor, requiring replacement.

First check that the two small hoses that connect to the DPFE sensor are connected properly.

And inspect the weld job, if it were leaking you would hear it.

The rear larger one goes to the lower tube on the EGR riser pipe.

The front smaller/shorter one goes to the upper tube on the riser.

1,000 word picture:

If they replaced these two hoses with fuel line or vacuum line they will melt. High temp Silicone hoses only here.

Auto parts stores sell the DPFE high temp silicone hoses as a set, pre-cut.

 

[rabbhill]

Thanks! The picture makes everything so much clearer! Now if only my engine compartment was as clean as yours.

 

[FR-425]

LOL That's not actually my engine compartment. Mine is cleaner!

No sweat.