00JeepGC

I just bought a 2000 grand cherokee about a week and a half ago. Everything ran smoothly until the exhaust fell off from the Y pipe to the tail pipe. I got that fixed the next day as all shops were closed at 8pm. Anyway, it ended up backfiring while driving. Now it's not acting right. i'll list the problems so it'll be easier to see. It's also an automatic, 6cyl 4X4
-struggles to get over 10 mph then when it finally does it jerks forward.
-has a hard time going from reverse to drive & vice versa
-it jerks like it's not getting gas and slows down around 20-30 MPH.

I'd like to fix everything on my own to save some money, i'm just at a loss on what it could specifically be, like is it a tranny problem, fuel pump, spark plugs, etc

dave1123

Just a guess, but try the catalytic converter(s).

00JeepGC

The catalytic is fine that was checked last week

onew1ckedxj

Check engine light on?

00JeepGC

yes its an evap leak, was told nothing major

dave1123

Okay, time to get out the multimeter. Check the resistance of the throttle position sensor (TPS) to see if it's smooth throughout it's range. If the shaft seal is bad, dirt can get into it and cause it to have dead spots in it. I screwed mine up by spraying Seafoam down the throttle body. Check the manifold air pressure (MAP) sensor hose for cracks or loose fit. Also, check all the sensor electrical connectors for bare or loose wires and all the vacuum hoses. I think on the WJ, the MAP sensor mounts on the base of the throttle body with an o-ring seal instead of a hose. OH...and check the throttle body mounting bolts for being tight. You can check for a vacuum leak by using a little carb cleaner around the base with the engine running. If it's leaking the cleaner will get sucked in and change the idle speed.

So far you haven't bought any new parts!