Truck started stalling if rpms drop less than 1000 rpms. How can I tell if it is the filter, pump, or injectors that are the problem. I didn't realize the filter and pump are in the tank.
Thanks

Are there any codes?Only way to check pump is a pressure test.How old is the battery?They will cause problems if it is weak or going bad.Rocky

No codes, it just started to stall yesterday when I would let off the gas in traffic. It drives fine till the rpms drop below 1000 and then it will stall. If I keep my foot on the gas it stays running. I work 30 miles from home and have a fear of it stalling and not starting back.

Sounds like it might be a catalytic converter issue to me.

Haven't thought of that. Is there a way to check?

Not sure but I think an exhaust shop can use a sniffer. I had one break internally on me and a similar thing happened to me. Then, it started to get worse. After a long drive, the engine started to "clog up" and before I knew it I could not go more than 25 mph. I thought it was starving for fuel so I replaced the fuel pump and still had the same problem. Had someone mention that it could be the catalytic to me. Took it to an exhaust shop and at first they said that wasn't the problem. I persisted and low and behold, that was the problem.

I put my gloved hand over the tail pipe and have someone rev it up. You can tell usually. Do it with another car or truck to get a idea of how much flow should be there. This method has not been proven or is in the factory service manuel.

Thanks, My son has the same model truck so when he gets home I will try that.

My 2002 360/auto Ram has done that exact thing on three different occasions and each and every time it was the battery cable. That paper thin strap that goes around the battery post cracked/rotted from corrosion resulting a bad connection so I would check all the cables/connections first since it's free to do. The first time it happened it left me stranded in the dark at work but a vise grip clamped tightly around that thin strap got me the 50 miles home.

I have new battery cables, but thanks for the advise

Stalling under 1000 rpms doesn't sound like fuel pressure or Cat to me.

Under 1000 rpms is when you need the least fuel or exhaust flow.

Sounds to me like a vacuum leak, problems with the idle air control valve, or possibly a bad O2 or MAP sensor.

1. Check for codes. I have people say there were no codes because the check engine light was burned out.
2. Look for obvious vacuum leaks. If it is a Magnum engine ram check for oil in the intake by looking through the open throttle blades. A common vacuum leak is when the intake pan gasket fails but it usually includes a little smoking.

3. Then start checking for Fuel Pressure, CAT back pressure, etc.

My

Hope it helps.

thanks, The engine light hasn't come on, and I went to a parts store and they can't check an 94 model truck. The truck hasn't shown any less power or drivability. It stalls when I am coming up to a light in town or coming off the highway to a stop light. I just started the truck and it idles fine. I let it run for a few minutes reved it up to around 2500 rpms and it idled back to normal just fine. The battery and cable ends are new as are the plugs.
Maybe just bad gas? The truck doesn't smoke and has 125,000 miles.

does it restart instantly? or do you have to crank a bit to get it to catch?

it does still sound like a tb or iac issue. if so it should reset after you try to restart and start fine.
I would see about cleaning it or replacing the iac motor.

the reason I say this, is under load the air requirments are different than you just blipping or reving. when you travel at highway or at speed, the iac is supposed to open somewhat based on total air load so if you suddenly have to slam on the brakes or whatever it won't kill the engine with the tb shut.

it sounds like it isn't opening enough.
so either it is too dirty(which technically would affect starting idle) or it isn't opening enough due to motor issues or whatever.

I have never looked at the numbers to compare so could be off, but that is what it sounds like to me.

It starts instantly. This is the first time it has ever acted like this. When it stalls, it starts back up like all is normal.

If you turn the key to run but do not start the truck the check engine light (oil, temp, batt, abs, etc too) should come on. If it does then the light is good. If not then replace the bulb.

On a 94 you should turn the ignition key forward to run (not start) and back 3 times, then leave it in the run position and the check engine light will flash the codes.

I theorize it is a vacuum leak. When you are off idle the ECU compensates for the extra air with extra fuel and you will not notice a difference.

When you return to idle the ECU has opens the idle air control valve to set the idle speed and suddenly you are now getting too much air and it dies.

This is my theory and speculation but I would check for a vacuum leak first.

A 94 magnum with 125K probably has a bad pan gasket IMHO. Unless it has already been repaired.

Thanks for the ideas. I will check on those in the morning and let you know what I find.

if it's not doing it anymore you probably had a slight clog in an injector. i'm not poo-pooing the suggestions above but run a quality bottle of injector cleaner through the tank at the next fill-up.

I have only started it today, not driven it anywhere, but I am going to do some checks in the morning. I really do thank you and all of the others for the ideas. The barracuda is so much more simple to work on. If it doesn't start look in the carb for gas. If you have gas then check for fire. Why did things have to get complicated?

Easy way to check if the intake pan gasket is leaking is to take the dipstick out and check for vacuum on the tube. It does sound like a vacuum leak problem to me. Also have had low trans fluid cause stalling on the trucks