truck stalled while driving

[91stranger]

So this is the second time this has happened to me. I'm driving about 45-55 mph, no issues, smooth shifting, idling, and driving. But when I go to slow down for a stop sign it will sputter and not respond to the gas pedal and the motor sounds weak then it dies. if I try to start it back up it doesn't start. after about a minute or two it will finally start back up as if nothing ever happened. Not sure what the cause could be for this. first time it happened I was going about 70 in heavy, heavy rain so I thought something got wet that shouldn't have. now that it happened a second time without warning it makes me worried. This is on my 99 3.0 auto trans, flex fuel if that matters. Also none of my gauges show anything wrong before this happens. check engine light has been on for my purge canister sensor but that's been on for 6-7 months. Anyone have ideas? I don't have the money to just throw parts at it or take it in somewhere. if I fix it then I have to do it myself and would like the first fix to be the only fix.

 

[Craig0320]

So this is the second time this has happened to me. I'm driving about 45-55 mph, no issues, smooth shifting, idling, and driving. But when I go to slow down for a stop sign it will sputter and not respond to the gas pedal and the motor sounds weak then it dies. if I try to start it back up it doesn't start. after about a minute or two it will finally start back up as if nothing ever happened. Not sure what the cause could be for this. first time it happened I was going about 70 in heavy, heavy rain so I thought something got wet that shouldn't have. now that it happened a second time without warning it makes me worried. This is on my 99 3.0 auto trans, flex fuel if that matters. Also none of my gauges show anything wrong before this happens. check engine light has been on for my purge canister sensor but that's been on for 6-7 months. Anyone have ideas? I don't have the money to just throw parts at it or take it in somewhere. if I fix it then I have to do it myself and would like the first fix to be the only fix.

Did it act like it was flooded when trying to restart? Did it spit some black smoke when you got it restarted. I had a 99 3.0 and it was doing the same thing. The coolant temp sensor was going bad telling the computer it was 20 degrees for instance when it was 90 outside causing the computer to dump fuel and flood it out. If you have a scanner monitor your cts and see what it is saying the current temp is. It is under 20 dollars. The cts sensor for the pcm is next to the upper radiator hose where it connects to the engine.

 

[91stranger]

Yeah it kind of acted like it was flooded or not getting fuel. No black smoke or any smoke from exhaust.On my way home it stalled at a stop sign and took 30 minutes before it wanted to start back up. Once I got it home I put my stock air filter and box back on(had a cheap cone filter but its been on for 10-11 months now), checked the MAF sensor, it was clean, removed the IAC and cleaned it as good as I could get it. Removed the throttle body and cleaned that really good. Both the IAC and throttle body were heavily covered in black carbon build up. Checked my plug wires and they are all sparking good like they should while it is running. I didn't have a chance to check them while it wasn't starting. Checked my cat to make sure it wasn't glowing red or seeming plugged. Anyone have ideas? Really want my truck to be reliable again since its my daily driver and I sometimes have my kids with me.

 

[RonD]

I would still read codes in memory, maybe a new one was added.

I know its after the fact but did you hear the Fuel Pump run for those 2 seconds when you turn key off and on for restart.
It isn't quiet, I would do it now, when its working, so you know what it sounds like, and if there is a next time then you can see if its a fuel pump issue.

Electric motors don't often stop once they are running, so long shot that fuel pump is stopping randomly, but they are hard to start, to get going, and that's usually when you find out an electric motor is dead or dying.

If power was being cut to fuel pump by bad FP relay or inertia switch then there will be a code in memory for that, for sure

Also the software in some 3.0l computers would cut fuel/spark if CAM sensor pulses stopped, and that would also set a code.
You can test if your software has this by unplugging CAM sensor and trying to start engine

 

[91stranger]

I forgot to add that I disconnected the battery for a few hours and today my check engine light is off and has not came back on. Its been on for a while now but it was a code for a purge canister.

 

[RonD]

You may still have the old codes in memory, I would check

 

[Craig0320]

I also agree with rond. My uncles 2000 f150 4.2 was dying randomly. Turns out fuel pump was failing intermittently. Sometimes it would stall while driving and just not start at all. You would cycle the key a few times and all of a sudden the fuel pump would kick on. We Installed a new fuel pump the next day and its been fine every since. Purge canister is evap related code. It will return until the pcm stores it to hard memory and turns the light off like mine did. Next time it stalls listen for the fuel pump running when trying to start as ron stated. Also, this still sounds a lot like the coolant temp sensor telling the computer to dump fuel and flood out.

 

[91stranger]

Yeah so far it hasn't stalled. I had it running at idle for about 20 minutes with no issues. Lunch break I brought it in the shop and had it running, changed the oil and had it running again for another 15-20 minutes while I vacuumed the carpet. Still no issues. Cant remember if I hear the fuel pump or not last time it stalled. I was pretty mad and cussing up a storm and not paying much attention to things around me lol.

 

[91stranger]

Still no help for this? Once again the truck drove to work and my whole lunch break just fine with no issues. I then go to Mansfield to get pizza and it stalls when I turn into the pizza place. Wouldn't start back up. Too much cars driving by to hear if the pump was turning on. Picked up my food and truck started. So I hauled ass out of there and of course I get stopped at a red light a quarter mile up the road and the truck stalls again. Had to sit at a green light looking like a fool for a few minutes when it started. Got it home where I then shut it off then start it back up with no issues. Please someone give me some advice. Thanks.

 

[Craig0320]

Go get a coolant temp sensor and put it in. Get the one next to thermostat housing. I mentioned replacing it earlier. It is like 15 bux.

 

[rangerenthiusiast]

Kinda reminds me of old-fashioned vapor lock. Out of curiosity, what happens those times it’s not starting if you nail the gas pedal to the floor and hold it there (yes, I know you’re not supposed to do that with FI). Will it start, or is it still no joy?

Do you have a fuel pressure gauge that you can hook up? I think some come with a hose attachment that allows them to reach up to the windshield so you can see them while you’re cranking, if you don’t have an assistant.

PS - Ron’s advice seems pretty solid.

 

[black_demon69]

Also check fuel pressure, fuel pump relay, and electrical connections to pump.
Might also check or replace fuel filter.

Too me it is like something is getting hot and needs to cool maybe ign control module.

Check connections to CKP Sensor

Good luck

 

[91stranger]

What is a ckp sensor? Never heard of that one. Will keep everyone updated. I don't have a fuel pressure gauge though. Going to replace the IAC and the coolant temp sensor.

 

[85_Ranger4x4]

Crankshaft position sensor.

 

[RonD]

Yes, CKP is CranK Position sensor, unlikey to fail intermittently, if they go then you have a No Start until its replaced.

CAM sensors on 3.0l can cause intermittent issues

But both of these are "monitored" sensors so WILL set a code instantly if pulses are gone or intermittent