Engine Performance problem
2001 Ford F150 6 cyl Two Wheel Drive Manual 164, 00 miles
6 months ago I developed an engine pinging right after having the truck repainted. Mechanic said it sounded like some paint fumes got into a sensor. It should blow through. This lasted for around 50 miles and went away for a few months. It than began to happen more regularly. This began as an intermittent problem and has developed into a constant problem. Mass Flow sensor replaced(was iffy), plugs and wires replaced, coil replaced. All other sensors test good. Mainly happens during light acceleration. Not affected by temp. Happens sometimes when engine is cold or hot. Unless truck is heavily loaded, goes away under heavy acceleration. Upped octane to 89 and to 91 with no change. More persistent during street driving than highway. All throttle and air passageway have been inspected and cleaned for carbon build up. Engine computer does not register anything for fuel/air mixture problems. Developed miss on cylinder #4 just before coil was replaced.
Ok a ping is either caused by overtiming, lean fuel mixture or overheating. So with that said I would like to check for a lean fuel mixture. Now first some info how old is the fuel filter? What plugs did you put in manufature and part number. Your truck does have the V-6 right? I also need to know if you have a digital multi meter so we can test a couple of sensors.
August, 21, 2009 AT 2:49 PM
I'm not testing this myself.
Automotive M& M is Sherman Oaks Ca. Is my mechanic and has gone through the whole thing over the laste 3 months. What information can I pass on to you from him to help with a diagnosis.
August, 22, 2009 AT 9:39 AM
Ok so then tell me what has he tested. Has you check the knock sensor has he done a live scan to see if it is running lean? Has the timing been checked to see if it is out range? Has the Cam and or Crank sensor been checked? How old is the fuel filter? Get back to me with what you can.
August, 22, 2009 AT 4:53 PM
I will talk with Him first thing Monday and get a complete list of all that has been checked and tested.
August, 25, 2009 AT 12:25 PM
OK great get back to me and we will see what we can do to get the truck fixed. Let you mechanic know that as a fellow mechanic I am not wanting to step on any toes, but I do know that sometimes it is great to put heads together and share ideas of what might be causing this.
August, 25, 2009 AT 7:54 PM
Some of these vehicles have had issues with this with no real fix.
The timing can't be adjusted anymore
What kind of oil and oil filter are you running? I know Ford has had issues with the intake o-rings but that is usually a idle issue more than acceleration issue.
I've heard of some guys finding the valves not hitting right on the passenger bank on those trucks and adjusting or replacing the rockers to fix it. But another thing is to check the EGR ports. As the EGR actually has ports to each cylinder and as the miles pile on, the clog up slowly and wind up blocking up shoving more EGR flow to other cylinders.
A easy way to find out is to block and plug the EGR and go for a road test
August, 26, 2009 AT 9:34 PM
I've been out of town for a few days and out of touch with the world. Cell phone do not work when you are hicking in the back country.
All above questioned items were tested with Live Scan and all have shown with-in spec. One issue that passed live scan may be the issue. The plastic fittings that hold the throttle body arm may be broken and the throttle is not opening correctly. The arm motor passes scan but the actual arm is not moving. He is pulling the intake manifold in the morning to see if this is happening. The arm is back behind the intake manifold and can not physically be seen with the manifold in place. He has had to change these plastic fitting before and believes this may be the problem.
All sensors work and pass scan. Timing is with-in specs. Octane ratings has no effect on the pinging.
The Mass Flow Sensor was iffi, and as I said before I had him change it to be sure. I will check back in tomorrow.
August, 27, 2009 AT 10:29 AM
Ok would you have you mechanic do me a favor. Have him check the timing at idle and then have him check it at 2500 rpm I would like to know what the total timing is. I know it can't be adjusted but it will tell us what the computer is doing with it so we can see if it may be an ignition module or? Get back to me with what he finds. Thanks.