Hey all,
My stock 99 L is currently stalling. It was running fine 3 days ago. I went to start it up today and it would stall out. If I give it a little gas to keep the rpm's up it would run...after I let go of the pedal...it would idle at 400rpm for about 5 sec then finally die. This is while it still in Park. At 400 rpm...it runs pretty quiet...kinda like it's only on 2 or 4 cylinders.

No DTC's (Diagnostic Trouble Codes) are coming up on the Instrument Cluster Diagnostics.


Sugguestions welcomed

Andy

 

fuel hose/fuel filter?
tell us about your mods if any

 

I didn't see or smell fuel leaking. My L is bone stock.

 

That is a coincidence. My stock 99 Lightning also started getting stalling problems about a week ago. Happened occasionally on cold starts. Would die as soon as it started as if was not getting enougt gas. Would happen two or three times in a row. Had to hold down the gas pedal to keep it running, which I normally never have to do.

Other than the stalling episodes, it runs great.

This started happening after I filled-up in another state (PA). Notice on the PA pump they use MBTE additive. Exxon gas.

Since then I filled-up with the local Shell gas I normally use and the problem has not repeated itself yet.

It was also interesting that the weather has generally been hot and very humid.

 

the hoses are a 2 into 1, inside the gas tank. some 99's has a problem with a .02 cent clamp coming loose and losing one fuel pump. you won't smell any gasoline

 

possibly a fuel pump problem, bad check valve, mass air meter(hose fell off), maybe humidity in the ignition system?

Probably something mechanical as your not getting dtc codes.

Hope something here helps.


Anthony

 

Sounds like a problem i had on my 97 V6 truck once. No codes so took it to the dealer and they reprogrammed the computer. Never had a problem after that. Hope this helps.

 

the fuel pump. or the hose's in the tank. That is what it sounds like. 99's had that problem

 

just putting in my 2 cents here. i know there are a few sensors on these newer motors now that control the idle. i think one of them is called an idle air control solenoid? and i also believe there is another little motor that kicks up the idle slightly when cold so it runs at a faster idle until it warms up and then the idle slowly comes down, im sure we all can relate to that, when u start it up in winter, it will run faster for the first 30 seconds or so. it is possible to have a bad sensor and get no check engine lights as stupid as that sounds. hope this helps.

 

dirty, caked-on oil, carbon deposits? This happens on EFI engs. from time-to-time.

Also, may be the IAC as posted by sscamaro--try cleaning it but I've had to replace more than one on earlier owned vehicles.

Dan

 

The next time it won't idle try tapping the IAC. Giving it a few good whacks will un-stick it. (They foul and stick) I don't carry tools with me so I used the jack handle until I could get it replaced.

It's located on top the motor almost directly under the right windshield wiper post. It has a hose feeding out to the left.

(When you whack it, don't forget to cuss)

If someone approaches say, "This is the last damn time I put MOPAR parts on MY truck!"

 

Thanks everybody for the tips.

When I fired up the L this morning it was about to stall again...so I held the rpms up to 2.5k for about 15 seconds. When I put it into reverse to back out of the driveway...everything seemed normal and didn't stall...so I went for a cruise around the neighborhood.

All seems well

My guess is the weather had something to do with it. We've had some really hot and humid days followed by several days of rain.

Without your replies I wouldn't have known about the clamp problem in the fuel tank, or IAC

...and yes it's time to clean my T/B again


Thanks again for the help
Andy

 

ford calls for the fuel filter replacement every 15,000 miles. Every one we have pulled off has been plugged up. Don't know for sure what is causing it but I just changed mine again, it had gone 15K, and it was really hard to blow through. Mine stalled once and I changed it and it hasn't stalled since.
noelvm

 

My Lightning starting stalling at cold start-up after the fuel filter was replaced at 15,000 miles. About a two weeks after. It could just be bad gasoline or moisture was or is causing the problem.

Also, my truck has always be a little hesitant to re-start after it has been run less than a minute or two, and then parked a few minutes before re-start. Seems like fuel starvation. Has to crank a bit to get going.