My engine is stalling at idle can you help me please?

truck will not idle can you help me fix it please?

Most of the time on Fords it will be a bad idle air control valve or collapsed pcv hose. Usually when the hose collapses it will trigger a check engine light with fault code P0171 or P0174 for bank 1 or bank 2 too lean. If no check engine light on then I would lean more towards the idle air control valve.

Idle air control valve on front of intake manifold is common idle problem. The Motorcraft part is a factory Ford part and is likely better than an OEM that may not be identical to the Motorcraft part. Scan the obdII port for trouble codes or take to a mechanic for scanning. I have a 1992 F150 that had same problem until replaced idle control valve (inexpensive and easily replaced). this guide can help fix it.

https://www.2carpros.com/articles/stall-at-idle

Let us know what happens and please upload pictures or videos of the problem.

Thanks for the additional information. we are a good team.

it was a vacuum leak by the brake booster all set thanks for the guides :)

In the cold months when we would 1st start it in morning it would not stay running unless you kept your foot on the gas for several minutes. We thought it was the coils so we changed those out. It ran fine for a day we stopped and put gas in it and it started running bad again. So we changed the plugs out but that didn't help so then we changed the master air flow sensor. That didn't help either. It will crank fine but is not getting fire it seems to be getting enough fuel because we can smell the gas after trying to turn it on. We did hook up a code reader to it but it came back with no codes. Any help is appreciated, thank you.

Hello,

I would start by removing the IAC motor and cleaning it, also do you hear a strange noise when the engine is trying to idle, this could be becasue the IAC motor has gone bad and needs replacement which is a common problem with those cars.

Here is a guide that should help you.

https://www.2carpros.com/articles/how-to-replace-an-idle-speed-control-motor-iac

Please let us know what happens.

Best, Ken

1999 Ford F150, 4.6L, 195,000 miles. The engine goes to a slow idle and then dies. At idle the heater fan slow down, like loss of power.?

check ICV valve. same as IAC. are you saying idle slows fan or fan slows idle? extra draw from alterantor does put a slightly higher load on engine. if it's too lean already this could slow down idle. idle slowing down lowers output from alternator so fan itself gets less voltage and slows down.

This guide can help us fix it

https://www.2carpros.com/articles/stall-at-idle

Please run down this guide and report back.

Changed the fuel injectors and after that it started stalling and shutting down and backfiring through the throttle body. It wont idle. Got a code for oxygen sensor so changed that. Still doing the same thing but then got a code for MAF. Changed that and no difference. Now got a code for the purge canister valve. I'm at a loss on what to do.

Hi,

First, let me know what codes are present at this time. Next, were there any issues prior to the injector replacement? Were the correct injectors used for replacement?

Have you checked fuel pressure to confirm it is within the manufacturer's specs?

Here is a link you may find of interest. It discusses the most common cause of backfires.

https://www.2carpros.com/articles/engine-backfires-while-running

Let me know.

Joe

The code is p0443. I don't have the pressure tester but when I check the pressure port on the fuel rail it's getting plenty of fuel.

Hi,

The pressure needs to be regulated to a specific pressure. There is a chance it could be too high.

Is the P0443 the only code you found? That is related to the canister purge solenoid. Have you checked for a vacuum leak at that point or if something was damaged or left disconnected? It is located near the power brake booster on the firewall under the hood. See the attached pic.

Also, I need to confirm if this is a 5.4L or the 4.6L.

Let me know.

Joe

It is a 4.6.L. I know that code is for the purge solenoid. Nothing is damaged or disconnected. There are no vacuum leaks that I can tell. I'm just at a loss because it will give me a 1 code and I will fix that and then that code goes away but gives me a different one so I'll fix that and it's like a never ending cycle.

Truck will only start when the gas is held down and then will not stay running.

Hi and thanks for using 2CarPros.com. I will assume you mean you are catching the vehicle in gear. The first things we need to check are for a good spark to the plugs and fuel pressure from the pump. Here are general directions for checking for spark:

https://www.2carpros.com/articles/how-to-test-an-ignition-system

Here is a video showing how fuel pressure is tested:

https://youtu.be/peh7-pFycyc

As far as the fuel pump pressure specific to your vehicle, the first picture I attached indicates the fuel pressure specifications. The next four pictures are of flow charts if you find a problem with pressure.

If you find that fuel pressure and spark are not an issue, the next thing you will need to do is check engine compression. Here are general directions for that process:

https://www.2carpros.com/articles/how-to-test-engine-compression

Here are general reasons for low compression:

https://www.2carpros.com/articles/the-reasons-for-low-compression

Here are specific directions for your vehicle:

Gauge check
AllData Editors Note - Ford does not provide a cranking pressure specification, only an acceptable range.

Make sure oil in crankcase is of the correct viscosity and at the proper level and that the battery is properly charged. Operate the vehicle until the engine is at normal operating temperature. Turn the ignition switch to the OFF position, then remove all spark plugs.
Set throttle plates in the wide-open position.
Install a compression gauge such as Compression Tester in No.1 cylinder.
Install an auxiliary starter switch in the starting circuit. With the ignition switch in the OFF position, and using the auxiliary starter switch, crank the engine a minimum of five compression strokes and record the highest reading. Note the approximate number of compression strokes required to obtain the highest reading.
Repeat the test on each cylinder, cranking the engine approximately the same number of compression strokes.

Picture 6 is of the acceptable range of compression.If you find the compression to be lower than 110psi, that is most likely the problem.

Let me know if this helps.
Take care,
Joe

Why were the original injectors replaced? Was there a problem or was it just a maintenance issue? Do you still have the old ones?

Let me know.
Joe

I put a re manufactured motor in a 1989 Ford F150 Lariat XLT with a 5.0 efi engine. I also replaced the distributor. The motor will start but only ideals at a 500 RPMs for about 2 minutes and then shuts of and will not restart until the engine cools down. It's getting fuel but the spark plugs get fouled quickly. Seems like the vehicle is getting spark but spits and sputters when I give it any gas and will not stay running. Can anyone help or have suggestions? Thanks in advance.

This sounds like the engine coolant sensor is shorting out lets change it out and recheck please. This guide can help as well

https://www.2carpros.com/articles/stall-at-idle

Please run down this guide and report back.

it was the sensor great job I knew I came to the right site :)

Nice work, we are here to help, please use 2CarPros anytime.