stalling and sputtering

Gabe · 10-28-2007, 07:18 PM

okay, while going down the freeway, the jeep suddenly starts to sputter and jerk. rpms drop rapidly, even though gas pedal is being pressed. rpms drop until it comes to a complete stop, or pedal is depressed. this only happens sometimes, and only above 55mph, or when tank is @ 3/4 or less. i pulled over and revved it and it sounded fine. took off and everything was better. refilled tank, 2hrs later, does same thing. poured in some additive, but no help.

fuel pump? tps?

**cheesycook** · 10-28-2007, 09:40 PM

I would start off by siphoning some gas out of the tank into a bucket. See if there are any floaters. You may be getting some junk in the tank that is blocking the strainer. Any check engine lights?

Gabe · 10-29-2007, 12:26 AM

cant get the siphon hose in there. Might have to take off the hose that goes in the tank and drop the tank instead of doing it from the gas cap thing, huh?

I dont know if I'm getting a code because my light has been on since I got a flowmaster. I'll have to go to auto zone and have them check it for me.

**Grewe02** · 10-29-2007, 02:18 AM

I vote TPS. When you're at a stoplight, do the RPMs jump around randomly?

Gabe · 10-29-2007, 09:54 AM

nope, it idles fine.

does anyone know how i can check it for fuel pressure?

**cheesycook** · 10-29-2007, 11:48 AM

Yeah, I would check the codes first thing.

Gabe · 10-30-2007, 02:12 PM

I got these two codes:
p0171 and p0138

Ive been having p0138 for about 8 months since I got my muffler and catalytic converter replaced.
p0171 could be
mass air flow sensor
oxyen sensor defective
ignition misfire
fuel injector problem.

**cheesycook** · 10-30-2007, 03:15 PM

I will do some research and get back with you tonight.

Gabe · 10-30-2007, 03:25 PM

I'm wondering if a new o2 sensor would fix both these problems. I know for sure it isnt a TPS now.

**cheesycook** · 10-30-2007, 10:45 PM

I checked and both codes are definitely a bad reading on the O2 sensor on the exhaust manifold. I would definitely start with a replacement. My information says that if it was the MAF sensor you would be getting similar readings on both O2 sensors. If that didn't fix it I would check the fuel pressure at the rail to make sure it isn't too high or too low. This could also be a misfire issue, in which case a complete tune up would be in order. If those don't do it another not so likely issue could be the fuel injectors. If it comes to those getting injectors for a Ford 5.0L is much cheaper. There have been discussions about that in this forum before.

Good luck bud.

Gabe · 10-30-2007, 10:47 PM

on the exhaust manifold? It says sensor 2 bank 1, meaning the one on the cat right?

**cheesycook** · 10-31-2007, 09:18 AM

My bad. I was tired. It is sensor 2 after the cat.

10-28-2007, 09:40 PM	#2
cheesycook Accident Prone Bonehead Join Date: Apr 2003 Location: Hermiston, OR Posts: 2,659 Profile Gallery Classifieds My Jeeps	I would start off by siphoning some gas out of the tank into a bucket. See if there are any floaters. You may be getting some junk in the tank that is blocking the strainer. Any check engine lights? __________________ 98 TJ 4.0 Stick 30 Lock-Right/44 True-Track,4.56. Fire RED. Optima Red top. 3" Full Traction lift, Cragar 352 Street locks w/3.75 BS. 32" BFG AT's. Sailcloth top. Classic4x4 tubular fenders. AtoZ Fab rockers and front and rear bumpers. TBT sportsbar and rear spreader. VDP 6 speaker bar. 2K Intake Manifold. Tuffy Speaker lock boxes. Power inverter. Cobra CB. Magellan GPS. Bed lined tub. 3core HD radiator. Olds airbox with Hummer snokle. Besttop seat covers with heaters. All running lights LED.Steering and oil pan skids. Mile Marker PE8000 winch. Currie Anti-Rock. Olympic trunk. Tuffy Console....and Buddha on the winch. :) And a child seat stained with mud. Hermiston, ORL AtoZ Where Zach makes me toys! Stu-Offroad, because I don't have a clue, but Stu does!

10-29-2007, 11:48 AM	#6
cheesycook Accident Prone Bonehead Join Date: Apr 2003 Location: Hermiston, OR Posts: 2,659 Profile Gallery Classifieds My Jeeps	Yeah, I would check the codes first thing. __________________ 98 TJ 4.0 Stick 30 Lock-Right/44 True-Track,4.56. Fire RED. Optima Red top. 3" Full Traction lift, Cragar 352 Street locks w/3.75 BS. 32" BFG AT's. Sailcloth top. Classic4x4 tubular fenders. AtoZ Fab rockers and front and rear bumpers. TBT sportsbar and rear spreader. VDP 6 speaker bar. 2K Intake Manifold. Tuffy Speaker lock boxes. Power inverter. Cobra CB. Magellan GPS. Bed lined tub. 3core HD radiator. Olds airbox with Hummer snokle. Besttop seat covers with heaters. All running lights LED.Steering and oil pan skids. Mile Marker PE8000 winch. Currie Anti-Rock. Olympic trunk. Tuffy Console....and Buddha on the winch. :) And a child seat stained with mud. Hermiston, ORL AtoZ Where Zach makes me toys! Stu-Offroad, because I don't have a clue, but Stu does!

10-30-2007, 03:15 PM	#8
cheesycook Accident Prone Bonehead Join Date: Apr 2003 Location: Hermiston, OR Posts: 2,659 Profile Gallery Classifieds My Jeeps	I will do some research and get back with you tonight. __________________ 98 TJ 4.0 Stick 30 Lock-Right/44 True-Track,4.56. Fire RED. Optima Red top. 3" Full Traction lift, Cragar 352 Street locks w/3.75 BS. 32" BFG AT's. Sailcloth top. Classic4x4 tubular fenders. AtoZ Fab rockers and front and rear bumpers. TBT sportsbar and rear spreader. VDP 6 speaker bar. 2K Intake Manifold. Tuffy Speaker lock boxes. Power inverter. Cobra CB. Magellan GPS. Bed lined tub. 3core HD radiator. Olds airbox with Hummer snokle. Besttop seat covers with heaters. All running lights LED.Steering and oil pan skids. Mile Marker PE8000 winch. Currie Anti-Rock. Olympic trunk. Tuffy Console....and Buddha on the winch. :) And a child seat stained with mud. Hermiston, ORL AtoZ Where Zach makes me toys! Stu-Offroad, because I don't have a clue, but Stu does!

10-30-2007, 10:45 PM	#10
cheesycook Accident Prone Bonehead Join Date: Apr 2003 Location: Hermiston, OR Posts: 2,659 Profile Gallery Classifieds My Jeeps	I checked and both codes are definitely a bad reading on the O2 sensor on the exhaust manifold. I would definitely start with a replacement. My information says that if it was the MAF sensor you would be getting similar readings on both O2 sensors. If that didn't fix it I would check the fuel pressure at the rail to make sure it isn't too high or too low. This could also be a misfire issue, in which case a complete tune up would be in order. If those don't do it another not so likely issue could be the fuel injectors. If it comes to those getting injectors for a Ford 5.0L is much cheaper. There have been discussions about that in this forum before. Good luck bud. __________________ 98 TJ 4.0 Stick 30 Lock-Right/44 True-Track,4.56. Fire RED. Optima Red top. 3" Full Traction lift, Cragar 352 Street locks w/3.75 BS. 32" BFG AT's. Sailcloth top. Classic4x4 tubular fenders. AtoZ Fab rockers and front and rear bumpers. TBT sportsbar and rear spreader. VDP 6 speaker bar. 2K Intake Manifold. Tuffy Speaker lock boxes. Power inverter. Cobra CB. Magellan GPS. Bed lined tub. 3core HD radiator. Olds airbox with Hummer snokle. Besttop seat covers with heaters. All running lights LED.Steering and oil pan skids. Mile Marker PE8000 winch. Currie Anti-Rock. Olympic trunk. Tuffy Console....and Buddha on the winch. :) And a child seat stained with mud. Hermiston, ORL AtoZ Where Zach makes me toys! Stu-Offroad, because I don't have a clue, but Stu does!

10-31-2007, 09:18 AM	#12
cheesycook Accident Prone Bonehead Join Date: Apr 2003 Location: Hermiston, OR Posts: 2,659 Profile Gallery Classifieds My Jeeps	My bad. I was tired. It is sensor 2 after the cat. __________________ 98 TJ 4.0 Stick 30 Lock-Right/44 True-Track,4.56. Fire RED. Optima Red top. 3" Full Traction lift, Cragar 352 Street locks w/3.75 BS. 32" BFG AT's. Sailcloth top. Classic4x4 tubular fenders. AtoZ Fab rockers and front and rear bumpers. TBT sportsbar and rear spreader. VDP 6 speaker bar. 2K Intake Manifold. Tuffy Speaker lock boxes. Power inverter. Cobra CB. Magellan GPS. Bed lined tub. 3core HD radiator. Olds airbox with Hummer snokle. Besttop seat covers with heaters. All running lights LED.Steering and oil pan skids. Mile Marker PE8000 winch. Currie Anti-Rock. Olympic trunk. Tuffy Console....and Buddha on the winch. :) And a child seat stained with mud. Hermiston, ORL AtoZ Where Zach makes me toys! Stu-Offroad, because I don't have a clue, but Stu does!