Rough Idle/Misfiring - HELP! (2006 F150 5.4L v8)
01-15-2016, 03:21 PM
#21
did you ever figure this out? I have a 2010 and I'm have about the same issue and I have done a few of the same test and they all seemed to give the same results I did a fuel pressure test and it started good then my fuel pressure fell instantly when I turned off the truck to 48 then within 10 minutes went to 42 and within 30 was down to 0psi, I've read that means there is a leak, there is no visible fuel leak anywhere so people are telling I possible have a stuck open fuel injector but no one can tell me a safe way to test it without buying some high dollar tester. Ive spent 1000 dollars in OTC testing gear already I'm about tapped out.. Could it be a fuel injector stuck open
01-15-2016, 05:37 PM
#22
did you ever figure this out? I have a 2010 and I'm have about the same issue and I have done a few of the same test and they all seemed to give the same results I did a fuel pressure test and it started good then my fuel pressure fell instantly when I turned off the truck to 48 then within 10 minutes went to 42 and within 30 was down to 0psi, I've read that means there is a leak, there is no visible fuel leak anywhere so people are telling I possible have a stuck open fuel injector but no one can tell me a safe way to test it without buying some high dollar tester. Ive spent 1000 dollars in OTC testing gear already I'm about tapped out.. Could it be a fuel injector stuck open
01-16-2016, 08:12 PM
#24
Misfire codes
I had the same misfire problem just a month or so ago except only on the #2 cylinder on my 2001 f150 with a 4.2 liter v6. It turned out to just be a small vacuum hose leak. This vacuum hose leak originally caused a code of "system too lean" on banks 1 & 2. A few months after that code was cleared and the engine was running normally it rough started one morning when the ambient temperature had droppd somewhere around 30 degrees overnight. Truck came up with another code that ended up being a misfire on cylinder 2 but the vacuum hose was the ultimate problem. I had checked the intake manifold thinking that the cheap plastic may have cracked somewhere around the seal but ruled that out with the use of a cheap can of intake cleaner and noticed that there were no areas around the intake sucking up any cleaner. Turned out it was about a 1/8 inch diameter hose that had a small leak near the elbow fitting and underneath a protective jacket that was quite hard to find but ended up being near the brake booster area. My truck originally was doing the same thing where it would be rough on startup or idle but any RPMs above idle there was no issue. Check your vacuum hoses. Cold start your truck one morning and stick your head in the engine bay and listen for any hissing that is not normal engine noise. If you hear even a light hissing while your engine is running with the hood cracked open this is probably your problem.
01-17-2016, 09:36 AM
#25
I have cleaned the MAF, AND the the throttle Body, and rest the idle and shift points and replaced the plugs and the COPS. I know I'm in a different group but I'm just looking for help anywhere. I was going to do a compression test yesterday but the OTC kit I have doesn't come with the correct adaptor to connect to my truck. Yeah me. So I'll be putting the plugs back in and trying it again another day.
02-01-2016, 09:19 PM
#26
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I have cleaned the MAF, AND the the throttle Body, and rest the idle and shift points and replaced the plugs and the COPS. I know I'm in a different group but I'm just looking for help anywhere. I was going to do a compression test yesterday but the OTC kit I have doesn't come with the correct adaptor to connect to my truck. Yeah me. So I'll be putting the plugs back in and trying it again another day.
Did you find a solution to it? Or anybody?
02-14-2016, 03:05 PM
#27
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I am completely stumped here. I just bought a 2006 F150 with the 5.4l 3 valve triton engine about 5 months ago with 85K mi on it. Now at 90K the truck out of the blue starts to idle rough and shortly after the check engine light begins flashing. Pulled into Autozone and scanned P0300, P0301, P0305. Misfires cylinders 1 & 5.
Here is what I have checked so far:
-Spark Plugs (replaced)
-Coils (swapped, problem did not follow coil)
-Fuel Injectors (swapped, problem did not follow injector)
-Cam Sensor
-MAF Sensor
-Compression Check (engine has good compression)
-VCT Solenoids (replaced, problem seem to very slightly improved but still idling rough)
The misfire really is only noticeable at idle and as soon as you press the gas it's barely noticeable at all at higher rpms. There is also NO rattling or NO ticking or clicking noises during startup or any other time. This led me to believe it was the VCT solenoid instead of something like the cam phasers but apparently I was wrong. Could it be possible there are other error codes that haven't been thrown yet? Surely there has to be a little more than just two misfires - how do you work with such a vague code or am I not fully understanding them?
I'm about ready to throw in the white flag on this and take it in to the dealership - which I fear I will be told it's major $$$$. This seems to be a common problem with these trucks however every thread I find regarding this issue on any forum just dies dead in its track with no solution.
I guess my next step is to check the "real" oil pressure and see if there's any oil flow issues?
Has anyone solved this problem?
Here is what I have checked so far:
-Spark Plugs (replaced)
-Coils (swapped, problem did not follow coil)
-Fuel Injectors (swapped, problem did not follow injector)
-Cam Sensor
-MAF Sensor
-Compression Check (engine has good compression)
-VCT Solenoids (replaced, problem seem to very slightly improved but still idling rough)
The misfire really is only noticeable at idle and as soon as you press the gas it's barely noticeable at all at higher rpms. There is also NO rattling or NO ticking or clicking noises during startup or any other time. This led me to believe it was the VCT solenoid instead of something like the cam phasers but apparently I was wrong. Could it be possible there are other error codes that haven't been thrown yet? Surely there has to be a little more than just two misfires - how do you work with such a vague code or am I not fully understanding them?
I'm about ready to throw in the white flag on this and take it in to the dealership - which I fear I will be told it's major $$$$. This seems to be a common problem with these trucks however every thread I find regarding this issue on any forum just dies dead in its track with no solution.
I guess my next step is to check the "real" oil pressure and see if there's any oil flow issues?
Has anyone solved this problem?
02-15-2016, 01:02 AM
#28
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Bad CATS
I am completely stumped here. I just bought a 2006 F150 with the 5.4l 3 valve triton engine about 5 months ago with 85K mi on it. Now at 90K the truck out of the blue starts to idle rough and shortly after the check engine light begins flashing. Pulled into Autozone and scanned P0300, P0301, P0305. Misfires cylinders 1 & 5.
Here is what I have checked so far:
-Spark Plugs (replaced)
-Coils (swapped, problem did not follow coil)
-Fuel Injectors (swapped, problem did not follow injector)
-Cam Sensor
-MAF Sensor
-Compression Check (engine has good compression)
-VCT Solenoids (replaced, problem seem to very slightly improved but still idling rough)
The misfire really is only noticeable at idle and as soon as you press the gas it's barely noticeable at all at higher rpms. There is also NO rattling or NO ticking or clicking noises during startup or any other time. This led me to believe it was the VCT solenoid instead of something like the cam phasers but apparently I was wrong. Could it be possible there are other error codes that haven't been thrown yet? Surely there has to be a little more than just two misfires - how do you work with such a vague code or am I not fully understanding them?
I'm about ready to throw in the white flag on this and take it in to the dealership - which I fear I will be told it's major $$$$. This seems to be a common problem with these trucks however every thread I find regarding this issue on any forum just dies dead in its track with no solution.
I guess my next step is to check the "real" oil pressure and see if there's any oil flow issues?
Has anyone solved this problem?
Here is what I have checked so far:
-Spark Plugs (replaced)
-Coils (swapped, problem did not follow coil)
-Fuel Injectors (swapped, problem did not follow injector)
-Cam Sensor
-MAF Sensor
-Compression Check (engine has good compression)
-VCT Solenoids (replaced, problem seem to very slightly improved but still idling rough)
The misfire really is only noticeable at idle and as soon as you press the gas it's barely noticeable at all at higher rpms. There is also NO rattling or NO ticking or clicking noises during startup or any other time. This led me to believe it was the VCT solenoid instead of something like the cam phasers but apparently I was wrong. Could it be possible there are other error codes that haven't been thrown yet? Surely there has to be a little more than just two misfires - how do you work with such a vague code or am I not fully understanding them?
I'm about ready to throw in the white flag on this and take it in to the dealership - which I fear I will be told it's major $$$$. This seems to be a common problem with these trucks however every thread I find regarding this issue on any forum just dies dead in its track with no solution.
I guess my next step is to check the "real" oil pressure and see if there's any oil flow issues?
Has anyone solved this problem?
03-06-2016, 06:52 PM
#29
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does a popping backfire sound mean my cats are bad and skipping mean a miss fire
Hi, had the same issue with my truck, I replaced the spark plugs, coils, new fuel filter, air filter, took out the fuel injectors and cleaned, cleaned the MAF sensor and still having misfires, did a lot of research, find out that a bad catalytic converter can cause misfires (P0420 error code catalyst system below threshold). My solution to my problem, cut my CATS open with a grinder then took off all the **** out then welded back and my truck now runs like new. Hope this help
04-09-2016, 06:16 PM
#30
Junior Member
My 2008 5.4L XLT was misfiring slightly and then rough intermittently and threw the P2135 code once in a awhile. I replaced the TPS and it now purrs.
Incidentally I somehow installed the new TPS wrong and the sensor was engaged to the throttle upside down causing the engine to have the throttle wide open at startup and it posted multiple throttle actuator codes. So careful when installing the TPS, it can go on wrong...not mentioned in the YouTube videos.
Incidentally I somehow installed the new TPS wrong and the sensor was engaged to the throttle upside down causing the engine to have the throttle wide open at startup and it posted multiple throttle actuator codes. So careful when installing the TPS, it can go on wrong...not mentioned in the YouTube videos.
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