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I have a 94 Ranger with the 4.0 in it and its running real bad latly.. when going down the road at say 55-60 and trying to just cruise steady it starts to pop and bang and it will most times blow flames out the exhaust.. no check engine lights or anything of that manner.. but once i step it down and bring the rpms up it runs great and will cruise 70 plus all day without missing a beat.. any help would be appreciated im headed out for harlan ky on tuesday and would like to be able to crawl obsticals instead of have to go wide open...
