1998 Jeep Grand Cherokee running very loud.

its in limp status maybe need to do learing gear
you can by the luanch in actuation test

Take it out & take it apart & go thru it

Something is wearing & noise isn't good

Didn't you go for a road test with the mechanic along

Why didn't the repair shop resolve?

could be a radiator leak whens the engine its hot

I would start with replacing the airfilter(if dirty) and fuel filter.especially the the fuel they clog up and give you sufficient pressure but no flow

It would be hard to guess at you electrical problems but get your brakes checked.It sounds like your pads have worn down to metal on metal.Very dangerous and can get expensive to fix the longer you leave it.A visual inspection can tell within minutes if this is the problem.If this isn't the problem the 2nd most common thing is a loose brake caliper or caliper mount.A friend with some mechanical knowledge will be able to check the brake pad thickness very easily and quickly with just a torch.Hope this helps

This sounds like one of two things. Depending heavily on your vehicles milage, you could need a new EGR valve or a new timing chain/belt. Thank you, Dana

pull belt off and turn pulleys until u find bad one. first start jeep with belt off and make sure its not in motor. check power steering fluid. dont leave motor running for 2 long with belt off

It sounds like a few different things or a combination of more than one.

1. The EGR valve
2. The catalytic converter
3. The mass airflow sensor

I would assume that there is something wrong with your exhaust again. Most likely its the exhuast donut gaskit that goes to the cat converter.