I just bought this 88' Cherokee with the 4.0L. It had been sitting a while and I need to drive it. I need help getting it to run right.

Here's the scenario. I have to pump the gas considerably to get the thing to start. I takes a few seconds. When it does start, it idles perfectly. If you push on the gas (in park), it hesitates and then revs to where you want it. If you put it in gear and then push on the gas to go, it bogs down, spits and sputters like I fed it diesel or something. If I then floor it, it gears down, revs up nicely and takes off smoothly, until I let off the gas. Even as I'm going down the road, if I give it the slightest bit of gas, it sputters; if I floor it, it goes. I don't get it - probably overlooking the obvious. Tell me what you think.

Just so you know: New plugs, wires, air filter, fuel filter.

Thanks so much for your help,
Sean

You said it sat for a while?
How much gas you have in it.
I would drain the tank and put some new gas in it along with some Gas Dry and change the fuel filter..........When I have ran out of gas I get this for a few minutes Put in some Gas dry and it clears it up..........Here in Michigan you get this allot

Could be bad gas, could also be a bad EGR valve causing too much backpressure. that will cause it to sputter at idle and have a hard time running.

make sure you check the vaccum system. my 90 4.0 does the same whenever the tube heading to the MAP sensor comes unplugged. if its never been replaced, it might be a good idea to replace that whole rat's nest.

get some good intake cleaner, like 3M or VP. get a good fuel system cleaner too..

good luck

Thanks for all of your help. I will try your suggestions. If you think of anything else, I can use all the help I can get.

Have a great day!
Sean

Also check the vacuum line running into the vavle cover they could be clogged. As far as the hard starting that is probably cause but a bad cermamic piece. I'm not sure exactly what it does but they use it to tunr off the fuel pump or quiet it down somehow. If you run with out it the fuel pump is noticably louder for some reason. It's located on the driver side fender right up on the edge and is a white ceramic block. Replace it and see if it starts better. Usually that is what it is.

I get that sputter too, i will look into all of this thanks for all the help.....