Mudboi222

Well, im having a little trouble figuring out whats going on with my Jeep. Its been sputtering when trying to accelerate and idling really rough. When its running it will idle fine then all of a sudden it slowly starts dropping and gets lower untill its about to die then it fixes itself and revs up and back to the right rpms and idles fine for about another 30 seconds. Then if i even try to drive it its a nightmare. Ill be driving and be on the throttle and can feel it in the throttle that its losing power and it starts backfiring and sputtering. Then i can let off the gas and floor it and it will throw you back in the seat untill you let out of it. Then its back to sputtering. So basically if i wanna drive anywhere i have to floor it. It started doing this about a week ago. I just did a tune up not even a month ago. The things ive done ever since it started about a week ago is, Fuel filter, Carter Fuel Pump that i ordered online for a pretty penny, Cleaned IAC, & then bought a new TPS sensor....Still no luck. I looked at my air filter and it was pretty dirty so i took it out for the time being to see if it helped...nope still didnt. I got a vaccum diagram and made sure all my vacums were all in place and they were. I dont know what else to try anymore :/ I just got my first job and can finally afford to get the things ive been wanting for my Jeep and then this happens :/ Ive blew 2 paychecks trying to fix this thing. If someone could please point me in the right direction so im not just throwing money at it. Thanks guys :/

cruiser54

Describe "tune-up" What parts did you replace?

Did you adjust the new TPS? And, did you get the tang on the TPS on the proper side of the throttle body linkage?

Ever clicked on the pink link in my signature and done post #1?

What kind of shape is the line from the throttle body to MAP sensor on the firewall in?

MAP sensor tube
There is a brittle little tube. It comes out of a rubber plug, low on the engine side of the throttle body. It runs back to the firewall, then up to your MAP sensor, behind the valve cover, higher up on the firewall. It has one vacuum line as already mentioned, with a 3-wire plug in the bottom.
CRUCIAL!! The MAP sensor will tell the ECU to dump fuel with little to no vacuum to the MAP. Any crack or blockage and it will be pig-rich. ( black smoke, fouled black plugs, must hold your foot to the floor to keep the engine running). You can pull the line off the MAP sensor and feel for vacuum with your finger. If it runs!
A visual inspection usually reveals any issues with the line from the throttle body to the MAP sensor.

Mudboi222

Yeah i made sure the arm is on the right side, whenever i push the throttle i can see it move the TPS arm. It didnt chance a single thing when i got the new TPS though. Couldnt tell a difference. In one of my old help threads you linked me to doing your post #1. I did that a few weeks ago. Checked again today. I was messing with the MAP sensor last night before i posted this and noticed when i take the tube off it runs almost identical to as if it was on and i was driving. It just dont do it as bad with the tube on.

EDIT: The vacumm to the map sensor was sucking hard enough to hold it to my finger. So id say its good. The line has no roughs looking spots to it or anything. & on the tune up i did spark plugs, rotor button, distributor cap, fuel filter & air filter.

cruiser54

That's a hell of a clue. Check the connector on the MAP, electrical.

Mudboi222

Yeah last night i noticed the clip wasnt all the way clipped in but it was at the top. Was just a hair off and wasnt clipped in. I clipped it in and still no difference. All this small stuff ive done, it seems to be idling a little better but still hasnt fixed the problem. I just finished putting a new Master cylinder and brake booster in today because it took a **** on me last night on my way to the haunted house lol. Ive been having problems out of the brakes since i bought it from my uncle. Finally got it fixed though. I feel a tad bit safer now & my brakes dont hit the floor anymore lol. But yeah im still stumped on this thing right now. Do you think i should get new plug wires and spark plugs again and see if that will fix it. Because now i remember i got all that stuff i said earlier except plug wires because i couldnt afford it at the time.

cruiser54

Get plug wires for sure.

Napa Belden or NGK.

How are the cap and rotor?

You're making progress!!

Mudboi222

Yeah im trying to fix everything now. I really couldnt afford to fix it the right way when i had no job so i was fixing as less as possible. So now i really want to make it right and fix it up really good. Im about to take the cap and all that off and thoroughly check all of that. I had a spare ignition coil under my back seat that my uncle had. I put it in there to see if it will change anything. Havnt had a chance to start it yet because im in the middle of replacing my back brakelines right now. I will deffinetly get some wires on payday though. Is there anything else you can think of that might be causing this?

cruiser54

Lots and lots of things COULD be causing this. Basics need to be done first, and this method of repair/maintenance will serve you well.

Mudboi222

Alrighty then man. Ill be back on here Friday after i get them wires and i might as well change the plugs again and gap them this time. What should i gap them to? & what plugs do you recommend?

Oh and btw i just finished bleeding my brakes. Its amazing what a new master cylinder and brake booster does haha. I was going down the road a minute ago and didnt realize i had them fixed now and was used to pushing them to the floor. I barely pushed them and they stopped on a dime just about.

cruiser54

What brand plugs did you use and how long ago?

.035" gap on the plugs.

Mudboi222

I dont remember but they were the cheap kind lol. It was before i got a job. I think Friday im also gonna replace my map sensor too. I took it off and noticed it also start instantly too? With the map sensor unplugged. Oh and btw i did your ground refresh again and made sure everything was nice and tight this time. Im running a little over 14 volts now lol. Shes pumping some power.