Time/miles between Oil changes

Change at 5k miles if you value the engine, especially if it’s not burning oil yet. Change the coolant every 50k or less for the same reason.

 

around 5k if you can, i don't think the months are as important.
read up on the egr circuit cleaning, all the best!

 

With 6 months corresponding to 4500 miles, yeah, stick with 6 months.

I'd second EGR cleaning, soon, including the intake manifold (it has EGR passages, important ones). My 2 cents: every 50k miles would be the max you should go between cleanings, if you don't want to blow a head gasket around 150K. See top two links in my signature, on a phone turn it landscape to see signatures.

 

Pro's doing this are kinda sparse; you're fortunate to have Tampa Hybrids, I believe they charge $600~800 USD, somewhere in that range. And it's a regular thing they do, and they do it right. @jerrymildred, a member here, was working part-time for them, doing a lot of those.

If you DIY it's virtually all labour, mainly depending on whether you replace the (pliable) intake manifold gaskets. The gaskets on the EGR components are metal, quite durable. I did replace the intake manifold gaskets on our 2010, seconds time around, but the original ones looked fine. That was about $35 CDN. Cleaning supplies: rags, brushes, a can of brake cleaner, and something a little more esoteric for the EGR cooler, either Oxi-Clean, or lye solution is what I'd use. Only on the cooler.

 

just to give you an idea of the work involved:watch

 

Videos 13, 14, 16, 17 and 24 here are also worth a watch.

If you DIY, do read the tips in top two links in my signature; there are ways to avoid a lot of the coolant spillage shown in the above videos. Or do the work in conjunction with a engine coolant change.

 

At least a $1000 at a dealer and they would try to talk you out of it without a proper code.

 

Dealerships will not "stoop" to cleaning, will only replace parts. They might bend that rule for the pipe between EGR valve and intake manifold, but other'n that, it's likely to be replacement. The retail prices for an intake manifold, EGR valve and cooler alone, are likely close to a grand USD.

And yeah, by the time a code manifests for reduced EGR flow, you're likely screwed.