01Merc
New Member
- Joined
- March 31, 2022
- Messages
- 2
- Reaction score
- 0
- City, State
- Texas
- Year, Model & Trim Level
- 2001 Mercury Mountaineer
Hello All,
I've been a lurker on these forums for awhile and always found them helpful, but this issue has been stumping me for awhile and I want to verify with others where I think my next step is. Please read through everything if you have time to understand what I have done and things I've noticed.
Info on the car for your reference: 2001 Mercury Mountaineer, 4.0L V6 SOHC.
I have had a misfire on cylinder 1 for at least a month, here is what I have already replaced: replaced the plug on cylinder 1, replaced the plug wire, and even replaced the ignition coil pack, the issue usually went away for about a 15 minute drive after each change, which might just be coincidence.
Currently, I was able to get my hands on an OBD that can connect to ForScan. I happened to be able to measure some values both with and without a misfire. I want to say it is the injector itself but I can still here is clicking or ticking, even when the misfire is occurring, so I am a little confused. Here are some screenshots of the data with a misfire and without a misfire.
Here is a still frame of the car misfiring:
Here is a still frame of the car NOT misfiring after about 5 minutes to allow for fuel trims to settle:
What I noticed is that INJ1_F is shown as "Yes" during the misfire and "No" when the engine is running fine. However, this only points that this is derived internally to the ECU that the harness, connector, or injector has an electrical fault. Maybe someone can shed some light on the accuracy of this reading.
Additionally, the LTFT during the misfire is pegged at 25%, but after the engine ran without the misfire for about 5 minutes to LTFT is sitting pretty at 2.34%
So from what I gather I know the misfire has to do with something from the ECU to the Injector itself. However, what I find confusing is that the injector still clicks with or without a misfire and I did rig up a noid light that showed when the engine was running the bulb flashed. Could the injector just be clogged, I couldn't see how that would tell the ECU there is an electrical fault though... So I am finding it hard to be 100% sure that the injector is at fault, but strange things happen so I wanted some input here from everyone.
Thanks!
I've been a lurker on these forums for awhile and always found them helpful, but this issue has been stumping me for awhile and I want to verify with others where I think my next step is. Please read through everything if you have time to understand what I have done and things I've noticed.
Info on the car for your reference: 2001 Mercury Mountaineer, 4.0L V6 SOHC.
I have had a misfire on cylinder 1 for at least a month, here is what I have already replaced: replaced the plug on cylinder 1, replaced the plug wire, and even replaced the ignition coil pack, the issue usually went away for about a 15 minute drive after each change, which might just be coincidence.
Currently, I was able to get my hands on an OBD that can connect to ForScan. I happened to be able to measure some values both with and without a misfire. I want to say it is the injector itself but I can still here is clicking or ticking, even when the misfire is occurring, so I am a little confused. Here are some screenshots of the data with a misfire and without a misfire.
Here is a still frame of the car misfiring:
Here is a still frame of the car NOT misfiring after about 5 minutes to allow for fuel trims to settle:
What I noticed is that INJ1_F is shown as "Yes" during the misfire and "No" when the engine is running fine. However, this only points that this is derived internally to the ECU that the harness, connector, or injector has an electrical fault. Maybe someone can shed some light on the accuracy of this reading.
Additionally, the LTFT during the misfire is pegged at 25%, but after the engine ran without the misfire for about 5 minutes to LTFT is sitting pretty at 2.34%
So from what I gather I know the misfire has to do with something from the ECU to the Injector itself. However, what I find confusing is that the injector still clicks with or without a misfire and I did rig up a noid light that showed when the engine was running the bulb flashed. Could the injector just be clogged, I couldn't see how that would tell the ECU there is an electrical fault though... So I am finding it hard to be 100% sure that the injector is at fault, but strange things happen so I wanted some input here from everyone.
Thanks!