Kmart164

Okay, 97 4.0 4WD. Engine started cutting out on me, and as I coasted onto the shoulder, it stalled and died. I cranked it over again, and at an idle, it was sucking air like crazy. I replaced the IAC, and it worked fine for 2 days. It just did the same thing again today.

I took the IAC back to O'reillys, because I thought it would be a defunct part, as I've had that happen before. I replace the new IAC with the new IAC, and still sputtering at idle, anytime you press the throttle, it stalls and dies.

But when it idles rough, it is sucking air in, hard. I don't know waht is related to the IAC as far as making it mess up, so if anyone else has had this problem, and fixed it, I would love to hear about it. Thanks in advance, guys.

Kmart164

Well, just did some research and from what I'm seeing, my TPS could be bad too, causing the IAC to not know where to sit, causing rough idle.

Kmart164

Nobody? Just replaced tps, and the same ****. Backfiring out of the intake when at WOT, then stalls. Hooking code reader up now.

Kmart164

One last bump, then I'll look elsewhere. P0300, P0301, P0302. Misfire(s), and misfires on #1 and #2 cylinders. Gonna pull plugs and seech.

XJ JoeyD

I'm not positive but I know some iac motors need to be "reset" at a certain position when there installed. So in theory if it was misalligned previously installing a new one at the same position may not fix anything. I'm not sure if the jeeps iac is like this but just something that came to mind. I would pull the plugs and see what they look like for starters, also I think the tps should have a certain voltage value, should be easy to check; I'll see if I can look it up in my factory manual later on today for you. Sorry if this doesn't help you out much, just trying to brainstorm a bit for you

leecarr

My 99 had all kinds of weird symptoms, replaced everything and it ended up being the CPS (of course it's the hardest one to get at).

Kmart164

Thanks guys. I replaced plugs, cap, and rotor. No luck. I'll try the crank sensor.

Kmart164

Well now the ****ing fuel pump hang priming. Pulling that tonight, and a new one will go in. The fuel rail had nothing but ****ing air at the schrader valve. I'm getting so fed the **** up with this thing.

leecarr

Sounds like what I did to mine, way more ************** at my shop though, things fly a lot too. I replace cap,rotor, plugs, wires, TPS even checked the compression, ended up being the CPS.

Kmart164

Just had a new cps put in, and here I am, 20 minutes later, on the side of the road, stranded, and my fuel pump isn't priming.

leecarr

Listen to see if the pump is running, the way it is made is junk. The connection from the pump to the output line is plastic (I would assume so it will break in an accident) and if it breaks the pump still pumps but just back into the tank. When you turn on the key the pump should come on and pump up to pressure then stop. If it keeps running and sounds like someone pissing in a puddle it could be broken in the tank.

Kmart164

I got the pump replaced, runs like a champ now. Sorry to revive this, just wanna let yall know.

kjc

Glad to hear you got it fixed. Did you keep the old parts you replaced, other than the fuel pump, I mean? Always good to have spares.

Kmart164

No, I sure didn't. They were old anyway, as in 1997 old. So I just tossed them.