Add notes about internal vs external MAP sensors

[Awk34]

No description provided.

[PSIG-dev]

Re: section
Existing text is misleading:
• "Use of 2 wire temperature sensors is highly recommended. Whilst ...". 1 or 2-wire of the same spec tolerances are equally accurate when installed and wired correctly. There are pitfalls to avoid with either, but to say they are inaccurate is misleading. Stating the recommended multi-point grounding from ECM to block would do more to ensure proper operation with any existing sensors than push for a possible change of type at cost and effort. See Andy Wyatt's articles for background on this.
• The other existing text is accurate and helpful without bias.
• The diagram could be interpreted not to industry standard, and insinuates all sensor grounds could or should be run to the battery (-) terminal, rather than directly to either the ECM dedicated sensor ground terminal or block as appropriate.
-- New text - I would delete all new text:
• "Some cars already run a vacuum line to the ECU". I simply have not seen this to be true, at least to any significant degree. Even if true, the statement does not add value, and appears to be an attempt at a pro vs con comparison.
• "Its calibration is already set up for Speeduino boards". This is true for many types other than internal, while it may add impression of intimidating setup if calibration is not on the preloaded list.
• "Many existing MAP sensors are mounted directly to the intake manifold". No added value to this obvious fact.
-- In a nutshell, I do not believe there is value to comparisons or pro vs con arguments. Users don't want to be told their stuff sucks, but how to use what they have, if possible, effectively. Give them info to use whatever they have, want, or choose, effectively. Perhaps a reference to the calibration section, MAP sensor testing, grounding tech or other helpful related info is appropriate to tie sections and components together. Creating Wiki material is tough. You have my admiration.