You take any carberated engine and try to convert it to fuel injection and you are going to have quirks. The main complaint with the Howell kit was that some had a hard time holding their own idle until it warmed up... this was the case when it was really cold outside. I live in Arizona and never had a situation where it was cold enough outside to be a factor. Howell has probably worked that problem out.
I was very pleased with my kit. I had it on a 1985 258 CJ7 for 3 years. I also own a 2000 4.0 TJ and to be honest with you, my CJ7 (with 110k miles on it)seemed to run stronger (havent broke in the TJ yet with only 500 miles).
For more Howell specific info you could join our users group....
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