I overheated a weekago(clogged hoses) and I now have a exaust that goes silent the exaust is completely removed and is a straight pipe from the header. The engine is running perfect and I fixed the overheating. But now I have no acceleration past 2md gear ad the exaust is less loud than before. I don lt want to tear apart the egine if it's the intake but I can't seem to diagnose the issue. It seems to have low or high back pressure and the acceleration is less overall. The idle is perfect and it seems to have a problem only with the acceleration. The mpg is definatly lower and I mixed some acetone in the gas to clean it out and that has helped but it's just made the mpg close to normal. I live in Las Vegas and the car runs better when it's very cold in the morning. The line to the accelerator pedel is not taut and I think I need o tighten it but I have not had this problem on a car before so I a asking for some advice before I go and replace all gaskets. Because that's alot of work that may not fix the problem. I truely think it's an intake manifold gasket but I cannot be sure it could be a distributor but I have no experience with those. Any ideas anyone in Las Vegas I can get to help out, definitely able to pay for the Assistance.
Thanks

Jeep Cherokee 4.0 2wd 1995
Has an Aftermarket Air Intake and a Straight pipe Exhaust no Cat or any pipes.
Ran perfect before overheating.