Isx help

[JimT]

You came here looking for help and you're getting it. You may not like the answers, but our engines don't run on good feelings. They run on science and engineering and an ever increasing amount of logic (computer) programming. I've only been on here for 4-5 years and I've seen countless people join, ask for help, then argue that the answers couldn't possibly be right because ... *feelings*. Some will follow through and eventually solve their problems and some others just can't accept that they, or the information they've been given, are wrong - they don't want to learn or grow. Most of the regulars on here, myself included, started out the same way, with a problem looking for help. You won't find the answers to every problem on here, but the collective knowledge and experience is priceless.

Stupid question, I know you said the dealer replaced the exhaust manifold and the CAC, did they use OEM parts or did an aftermarket part get swapped in? Simply fixing your possibly long standing exhaust and boost leaks by replacing the manifold and CAC could account for the higher boost pressures. But if they used a different CAC than what was originally in there then that could be throwing things off too. The ECM is programmed to expect very specific parts and bases many calculations on the parts it expects to be installed. It's one of the biggest problems with the cookie cutter deletes because those programs rarely match all the parts, both inside the engine and out. And that's before any changes need to be made for the actual delete to take place. You would think the dealer of all places would use OEM parts... but it's bad to assume anything these days.

Also, if you go browse through the Bad Delete Collection thread you'll notice that one of the other big reoccurring problems is that many deletes block or hide fault codes from being reported. Not just on the dash but also from diagnostic tools like Insite or JPro or whatever. This leads people to think that everything is fine when in fact it isn't.