HELP!!!
I recently purchased a '98 with around 78k miles. Brought it home and dropped it off at a shop to run through everything to ensure it was all on the up and up. All good, except some idle problem according to the shop owner. So I proceeded with more mods. I put on new "mister" styler injectors, changed the exhaust to Borla header-back with a magnaflow cat (the factory wouldn't fit), and put a spectre intake on it as well.

Then things start getting goofy. While driving it will stall, but sometimes I can gas through it. At around 50-60 mph it will do this weird split second electrical shutoff, and jerks for a second, but will continue. It also feels like it loses fuel pressure and comes back up and backfires. The only code it threw was the P0700. So I started changing sensors. I've changed the TPS, MAP, IAC, and NSS to no avail. So I started thinking about ignition. I pulled the cap and rotor tonight and they were both slightly corroded so I changed those. Didn't have a chance to test drive it, but I let it idle and at about 5 minutes it starting idling pretty rough. I also flashed, or reset, or whatever the ECU tonight too. Only things I can think left might be the TCM, CPS, bad coil, bad fuel pump, or maybe just a bad ground somewhere.

I feel like I've just been throwing money at it blindly, even though it seems like I've followed rational thinking on changing what I have, but I'm not sure

 

Forgot to mention that after it was checked out and he told me about the idle that it never failed on me until I I finished the mods. Never noticed it anyway.

 

perhaps a bad ground. usually when the cps goes bad, the jeep will just shut off without being able to "gas thru it". could be an issue w the computer. try shaking the wires that connect to it while the jeep is running and see if it acts up. also does it always start right back up after it stalls?

 

I had something similar like this with 98, and it was just the idle air control system, it's on the back of your throttle body and looks like a plug.

 

Sometimes it will start right back up, but usually tried to die again. I'll check some of the wires tomorrow. You think just ones into and out of the ECU?
I've already changed the idle air control sensor

 

Still no fix. I'm stumped.

 

check fuel pressure with a gauge.

 

Mine had this problem I checked the ground strap off negative cable on battery was hooked up good and I thought that wasn't an issue but later it broke off of nut holding the wire to the body and it was too rusty to remove the nut. I drilled new hole and put on new wire for strap and it hasn't happened since. After cutting that wire I was surprised how much corrosion there was hiding in that wire and every once in a while it would cause my jeep to stay in overdrive and I would have to shift it manually until I would shut it off and crank it back up.

There is nothing more infuriating than your own jeep brake checking you.

 

I have the same issue. It idles low, above 80km it stutters and feels like a misfire. I replaced the IAC, MAF, entries throttle body, TPS, O2. plugs, wires, wota cap, distributor . Coolant sensor.

getting the following codes p0700, p1388,p1491,p1281,p1492.

most of the codes are cause by the last owner jumpeted the ASD relay, jumpered the fan to be on all the time. We live in the Caribbean.

Really would like to get this issue sorted. It's drinking gasoline.

 

I have the same issue, any updates??

 

It really sounds like a bad ground at the top of the circuit. Work your way away from the battery with the ohmmeter and you'll find it. Could be in the battery terminal, at any of the studs, or in a connector.

Get a multimeter and long piece of wire with alligator clips on both ends as a extension. Connect the extension to the negative battery terminal and one lead, then poke around the sensor grounds with the other lead and look at the resistance readings between the neg stud and sensor grounds on top of the manifold, alternator body, and ground strap from head to firewall. They should all be less than 1-2 ohms.

If the grounds all check out, do the same on the positive side.

If you rule out a bad electrical connection things could get interesting in here.

 

Clean the throttle body and the " idle motor" with carburetor cleaner. Get a VOM and a shop manual and test sensors prior to replacing them. If that doesn't solve your issue, Clean and test your injectors, check fuel pressure at the fuel rail - be patient and good luck