This is the 3rd time ive posted this since ive joined the forums, ive been a member for about 5 - 6 months or so. Would really really appreciate your input!

My engine stalls to the point it wants to die, I dont let it go that far because i'd be scared it would die on me and not start back up. It happens when I let it sit at idle, whether a stop sign, red light, or just sitting there in the morning let it warm up. It ONLY happens when shes not moving. And it seems to be completely random, whether its once a month, or once a week, or once a day, I can go the whole day without noticing it, sometimes. If it does stall, once I give it gas it goes away or at times when im at a red light and it does it, ill throw it in park, turn it off, then turn it back on and it runs smooth as butter.

Ive done wires, plugs, dist. cap, rotor, cleaned the air filter, cleaned the throttle body[IAC, MAP, and the PPS]. Its a 1998 5.9L 1500 4x4, I always rune 89 Octane [Although I dont know what was ran before, ive been at least the 3rd owner].

My guesses are: 1. The engine was replaced at 121k miles, ive put 4000 miles on it so far, same size engine, with 71k was put in at the time, could they of messed up on something that im not catching?

2. Transmission had some repair work done, what exactly I dont know, but if its important in you trying to help me out I can go pull the recepit out of my files. Although I dont think the trannie has anything to do with this.

[Engine/Transmission had work done before I bought it]

3. One person responded last time, saying possibly the fuel filter, as most of you know this is NOT a fun thing to get to and change. Im trying to leave that one as a last result being it sucks ***!

Please guys im at my wits end with this, as I always state im fairly new to working on trucks n cars[Only been into it about a year], ive learned a lot through this forum and tinkering with mine and buddies cars. Anything you put out there im willing to look into. My dad seems to be a wizz with trucks, and he doesnt even know what to suggest. Most shops around here are charging 120$ + for a diagnosis, I dont want to pay that if its something simple.

Help!!! [:@]

 

It might not be the fuel filter, it might even be the fuel pump itself.

Have you had it checked for any codes? Is the CEL coming on at all? Even if the light isn't coming on, if you haven't checked for trouble codes, I would see if there are any in there. There is a DIY in that section of the forum that might work for you to get the codes (if any), otherwise you can take it to almost any mechanic and he can hook up a tool to it to get any codes.

If the tranny isn't making any funny noises, and is shifting right when the truck does run, I highly doubt its that. Another possibility is the computer itself.

 

no one said TPS yet? Same thing happens to tons of people.....for some the cleaning trick in the DIY thread works(my case) Otherwise $30 part

 

I doubt its the tranny too. I had a94' chrysler LeBaron GTCthat used to do something very similair to this, and it turned out to be the fuel filter. Have you ever ran any fuel injector cleaner through it? If not, go grab a can and add it to your gas tank, cheap, can't hurt its worth a shot.Also places like Jiffy Lube (which iHATE) can do it throughthe vaccum line and that really cleans stuff out.

 

Maybe a loose wire somewhere that is causing a bad connection somewhere, because it could explainwhy it is not a constant problem. I have a customer that bought a mid 90's model F-150 that the previos owner had done some work under the hood and left the wiring harness loose and every so often it would act up. Since you have replaced everything else I would start with checking everything electrical and make sure that everything is good and tight.

 

I'll look into getting the codes check, now that I think about it I think Auto Zone lets you do it for free if you let them hold onto your license.

Yes, ive ran fuel injector cleaner, it was Lucas, forgot to mention that, sorry. But you said places like Jiffy Lube can do it through the vaccum line? What exactly are they doing through the vaccum line?

Will look at the wiring too, see if anythings loose.

Thanks a lot guys for your input, will update you on what happens.

 

Have you tried TPS? mine was surging then sputtering till i removed couple bux for torx screwdriver and about 30 for the part. Also try Seafoam my truck had a slight vibration which i hated and ran can of seafoam thru TB and it dissappeared after plenum and various minor replacements i cant feel if its on or off. BTW 2000 ram, so go give the tps a shot i was cleaning mine but for 30 bux skipped the hassle of putting on and off.

 

i'm asssuming you can keep it running with light pressure on the gas pedal....
also assuming you have not replaced IAC or TPS.

i'd replace both, using only SMP or Mopar brand parts.
TPS should be about $40-50, IAC about $50-55 for SMP brand.
i'd avoid autozone and advance, including GP brand. I've had unbelievable bad luck with both of these. see prev posts by me.

the IAC is responsible for maintaining idle rpm, whenever the TPS is NOT telling the computer you are mashing the gas. however, don't confuse the TPS's signal to the pcm and your foot actually mashing the gas, as the tps can send false signals. typical idle rpm is between about 600 warm and 1000 cold. the IAC does this by extending/retracting a plunger into a well, which varies the amount of air that enters the intake, and which bypasses the closed tb butterfly plates.

The tps' job is to tell the pcm how much, if any, you're mashing the gas. when you do mash the gas, it opens the butterfly plates and allows air in, negating the functionality of the IAC bypass port.
also - clean the IAC port on the back of the TB.

 

Try the above TPS and IAC things 1st. But don't be too quick to discount the trans. Go check your reciept and see what was done but here is something to look out for. The shop that did the repair may NOT have replaced the fluid with +4 (synthetic) and may have used an older (non-synth.) formulation. That can cause the torque converter to grab at lower (idle) RPM's (especially if the fluid is old) and the result...stall! Not saying that's what it is, just something else to ponder.
Can't believe you got no responses to this problem on earlier attempts. Lots o' guys have had idle issues and there is a ton of info and really helpful people here. You sure you were on THIS forum. lol

 

When you ride is giving you trouble always start simple first.
For your Prob the first thing I would do is check the vacuum hoses. A crack in your vac hose can stall your engine at idle.

Jeff