DI Stall when stop

[leadfoot]

Ok, I decided to start this thread with my problem. 1997 DI 154K. A couple of years ago, started with issues about starting when hot. It would start but verily kept idle and would not accelerate. After kicking the gas pedal several times (just to keep it from stalling) it would run normally. That was at about 135K. At that time I replaced the fuel pump, the fuel filter, the Crank Position sensor (I think that is what is called, it is in the back of the engine between the engine and the transmission on the driver's side), I cleaned intake and MAF and other things, eventually the starting issue went away, but went into high idle for a few days and then problem went away, never knew the real cause. Run good for about 18K. Now at 154K it started with the issue: runs very well, but randomly it will stall when stop. Light engine came on, checked codes and they were O2 sensor related, replaced O2s, spark plugs and spark wires with Magnecor 8mm. Check engine light went off, but the stalling issue remains the same. The car always starts right up in the morning, no matter how cold (central Illinois), but when warm, it may start and die after a few seconds, and then at some traffic light, it will die, but starts right back up. Someone mentioned the fuel pump relay, went to check and found a vacuum leak instead. Fixed the leak and took it for a ride, it died once out of four stops, but runs like a champ in between! GRRRRRRRR Any Ideas?

[Savannah Buzz]

Perhaps the fuel temp sensor is haywire, and telling the ECU the wrong info. From RAVE:

Engine fuel temperature sensor (EFT Sensor)
This is another resistive sensor. Located on the fuel
rail it measures temperature of the rail rather than the
fuel. The resistance varies with changes in
temperature. The signal is used to increase the
injection pulse time when undergoing hot restarts.
When the fuel is hot, vapourisation occurs in the rail
and bubbles can occur in the injectors. Increasing the
pulse time flushes the bubbles away, and cools the
fuel rail with fuel from the tank. The fault may not be
evident to the driver, there may be a hot restart
problem. The fault is indicated by illumination of the
malfunction indicator light (MIL) on North American

specification vehicles

But if no codes, the crank position sensor is usually number one suspect. You can also use a data reading code scanner to check the IAT (air temp into the MAF) and the coolant temp, these sensors have to "make sense" or the ECU thinks you are in Alaska at -40F or the desert at 150 F. So by looking at their values, you can see if it seems reasonable for your location.

[EricTyrrell]

Sounds like your IACV is broken or clogged. I'd clean it out well using a rag, small brush, carb cleaner, etc. New one is about $40.

[Disco Mike]

I would start by cleaning the t/body and the IAC, making sure to get all the carbon build up of the plunger and out of the manifold hole.
If that doesn't fix it, then yes, you may need a new IAC which you should have programed.

[leadfoot]

Help me here please. I am confused. You advise to clean the IACV. I've read somewhere else in the forum that if you "move" the plunger, you have to have it re-programed. How do you clean it? I got it out and it has a lot of carbon build up on the shaft, not the tip . I sprayed carb cleaner, but that is not enough to remove the carbon. How to remove the carbon without moving the plunger? Somehow I got this all wrong. Please set me straight here.

[Spike555]

Take a old tooth brush, soak it with carb cleaner, scrub the plunger.
Just do not pull the plunger in or out or twist it, thats all.
Then take some pipe cleaner and spray the port it seats into and ream it out with pipe cleaner.
Once all nice and clean put it back, plug it in and start the truck.
If you get in the habit of cleaning it once a year along with your throttle body you can avoid these simple problems.
Memorial Day weekend is a nice long weekend to do "spring cleaning" on your truck.

[Rovin4life]

and don't forget the throttle body itself, had it happen to me, would stall at idle until Icleaned the crap out of the throttlebody.

[leadfoot]

Reporting back.
Thanks guys!!!! there was no gasket on the IACV. Checked the RAVE, and sure enough it mentions a gasket for the IACV. Plus it was dirty. I cleaned all well, as instructed here, put some liquid gasket, went for test drive and no issues at all. I am not calling victory just yet. We will see in the next few days, but so far so good. Thanks again for your advise.

[Spike555]

Remember...spring cleaning.
Your wife cleans the house, you clean the cars, fair trade if you ask me.

[leadfoot]

I followed the advise someone gave here in the forum about a generic IACV from Advance Autoparts. It works great!! $52.00 It calibrated itself within a few minutes like the instructions said it would.