06 Freestar 4.2, under medium to hard acceleration load in any gear I am getting "ping" as dealer puts it. Sounds to me like valve float or piston knock. They tried to say octane...I use 87 as recommended, they said change gas station.....wife does not use the same station regularly. I am thinking that it is possible the intake runners fluttering as this happens exactly between max torque (268 @ 3650rpm) and max horse (201 @ 4250rpm). It is not easy to here and you have to get on it to here it.........Anyone have anything like this.........................PS bone stock no mods............

Couple of possible things to look at depending on driving habits and mileage. Could be"HIGH RPM LEAN-OUT" caused by dirty injectors. Have you run any type of quality fuel injector cleaner thru your buggy? Could also be caused by carbon buildup in the combustion chamber. This is normallycaused by constantshort drives where the engine doesn’t get to operating temperature or the engine never reaching high RPM’s. I use AMSOIL's P.I. fuel additive to keep my injectors clean (I still run 1 oz./10 gallons even on their new formulation) and my water injection eliminates carbon build up in the cylinders. But that's just me and my way.

I first noticedit around 4-5kmiles but was not able to nail down how to get dealer to repeat,now have 22k and can make it repeat if driven as instructed. The RPM range is only in the 60 to 75% range. The engine pulls strong through 5200rpm. I live in NJ and daily trips are short distance long running ie average speed for a daily drive is 20 to 30 mph and the engine does get to full temp. High RPMs are usually reach due to accelerating on and off highway.

Hmmm...got me...I'm at almost 40,000 miles on my 2004. Only noise out of my engine is fuel rail knock when the engine is cold, but that slowly goes away as the engine warms up.

Like I said I think the intake runners are oscillating as it is a the point the engines is producing peek power output and the intake runners are used to tune the intake for max performance...........

Looked in my Freestar shop manual and could not find a knock sensor which would prevent the engine from pinging so I would take the advise of the dealer and use higher octane gasoline.
Also the advise about the fuel injectors by "use common sense" no pun intended sounds sensible to me.

I have the same think on my 2006 Ltd. In reading other forums, this is not uncommon. Higher octane does not fix the issue. Bummer Ford engine design.

J

Try the fuel system cleaner like he said, stay away from discount gas, and check and see if the MAF senor is dirty(the wire.) Also , have you changed your fuel filter?

I have had the van severiced at 17k, at which time I believe the fuel filter was replaced. The van is well kept in general. If it was "knock" it would happen at any engine RPM under load correct???? This happens only between 3600 and 4200and must be under moderate to heavyaccelerating load, IE it will not do it if you are rolling 3800 RPM costant even under load. And I have dropped Lucus fuel cleaner in the van...................

If you have exhausted all other possibilities and suggestions on this forum I would look at something loose somewhere and maybe you are dealing with a rattle and not a pinging condition which as other members suggested can only occour under load. I find the intake runners fluttering a bit far fetched as there are lots of these engines and it would be a more common problem. Of course anything is possible.

Do you really drive a van in the 3600-4200 RPM range that often? If the ping is not heavy, and not present under 99% of daily driving condition, I wouldn't wory too much about it. Easy fix, keep your RPMs down.

Jakers, I believe when al is said and done it will be a weird quirk to the 4.2L V6 in the Freestar. As another psoted he had heard of the same issue, possibly had it in his, and I haveconfirmed other forums have discussed this issue. However, I have not found anyone that has determined the cause. The one thing I did come across is Helmholtz Resonance in relation to VLIM intakes http://en.wikipedia.org/wiki/Variable_Length_Intake_Manifold, it may be that it is a resonant sound due to the intake. In addition, my hope is that if someone else comes across the issue they can add their knowledge and expereinces.

94BLK5.0, You are correct, I do not usually utilize the power curve for the engine (ie peak torque 3650 and peak Hp 4250) and I am not over concerned with a major mechanical issue resulting from the sound. However,it is the wife's car, it carries my kids, and it had best bring them home safely. So with that I take it as my personal responsibility to make sure that the van provides reliable transport to the best of my ability, or I get rid of it...................

2 TSBs as of mid July 2007 dealing with the intake runner that tunes the intake. The basic I have gotten from my dealer at this time is:
1. Possible moisture entered PCM and or PCM connector,ping or knocking is one of the possible symptons of this.
2. Plastic bushings worn or damaged on runners orservo causing runners tovibrate.
I am scheduled to bring the van in the8/27/07. I will post what if any was found.

The lastest I have from the head of service at my dealer is that Ford is saying it maybe "Normal". He does not like that response and was/is looking for an 06 with a 4.2 to test it for the noise. I am also trying to get a freind of mines 06 mercury to run laps with for the same sound. If I ever get a final resolution I will post it. I apprecate everyones in put and help.
Thanks

I had a similar sound with my 2004 freestar when I first got it and I also had it with an earlier 4.0L in a ranger. This problem is just carbon build up in the combustion chamber. If this is your wife's van, she probably doesn't run it very hard, ie above 3500 rpm. This aids in the production of carbon. The fix for my van was to take it on the highway and run it in 3rd gear and accelerate hard, ie on the floor, and then let off and accelerate hard again, do this about 6-10 times and you should hear the noise get less. You need to heatup the combustion chamber to burn off the deposited carbon. The higher the revs the better and the more load you can put on the engine the better, ie up a hill. Afterdoing this with my Freestar, thepinking noise is completely goneunder allloads and rpms. The exactsame thing worked for my old 4.0 L engine. Worth a try...[8D]

I would assume that a five hour tow with an 1800lb trailer running at 3000rpmwith on and off ramp and various starts/accelerations pushing the revs between 4 and 5k would most likely clear carbon buildup of the nature you reference? Additionally, I have picked up on this noise since the van had 4000 miles or less. In addition, I havea freind witha mercury that produces the same noise under tha same conditions................

Just out of curiosity, have you tried going to a higher octane fuel to see if the ping goes away? It's possible that the PCM programming isn't correct for the timing advance at higher RPMs. It's also possible that the MAF isn't properly calibrated from the MFG causing it to readless air flow than actual causing a LEAN condition at the higher RPMs. I have a 2004 without the problem and you have a 2006 with the problem. But then again, I also run copper core plugs gapped at .48 in conjuction with water injection.

Have you checked the metal rods that connect the IMRC motor to the runners in the intake manifold? Have seen a couple of newer F-150's with the 4.2L with this concern, the rods aren't connected to the runners or electric motor causing the ping condition.

BRETM; Yes, actually there is a TSB for premature failure of the plastic bushing on the actuator links.

U.C.S.- The ECM was reflashed as one of the 1st steps, to provide the most upto date program and specs to the ECM......

Update on my pinging 06: I ran a can of Chemtool through the van and the pinging under load is gone. I'll see how long it takes to return....

Jack

It would not be your intake butterfly shuttering. think about it, if they were occalliting that fast, how would the engine be performing? I would think that it would feel like a misfire. What you have is a lean condition, possibly caused by the maf meter, or the calibration level of the software in the computor. Another thing could be the fuel, in general. Most of the fuel we process today comes from a high sulfur content.

Guys,

I have the exact same problem with my '04 F150 Heritage 4.2l. I get a pinging sound between 65 mph up under acceleration or climbing hills. It was an intermittent problem and didn't do it all the time. I tried different octane and it didn't make a difference. The check engine light came on and I took it to a dealer who said it needs IMRC bushings. I still haven't got it fixed because they didn't have the parts in stock, and wanted $1000 to fix this. I tried different brands of fuel, switching from Chevron to Shell, and thought I had cured the problem. Then, while driving on the highway with no problems, I "gunned" it to pass a car. It started pinging again and went back to it's old ways. So now the problem is back again after I pushed the accelerator pedal further than normal. With what was written here, what I have been through, it leads me to believe the IMRC valves are loose somehow, and I activated them when I accelerated hard to leave them in a loose position, and as soon as I spend $1000 to fix it, the problem will go away. So far, after 50,000 miles, this is the only problem I have had with this truck, and from what I hear, those IMRC bushings are a weak link on the 4.2L Ford motor.

Update...Tossing another wrench in this fire. I went to bring the van in to the the new service manager just after the New Year. Very cold morning just above 20 degrees. Got motor warm and could not simulate the noise in the same location as previously. The noise has been heard at tempatures over50 but who runs around with the windows down below 40?? It is mine and the new service managers opion that it is most likely a lean condition in the motor due to the programming (which will most likely not change, and yes the PCM was flashed this summer with the latest updates). The reasoning is that the only changes were air temp and of course fuel blend (winter vs summer), and that this only happens during peak performance (ie peak torque 3600 Peak horsepower 4200), with the understanding that the PCM is tweeking every once of power with the minimualist of emissions.

Your over 50° F temp just clicked in my head. I believe that theACT isn't used below 50° F.You could have a faulty ACT in your MAF since the problem doesn't exist below the 50° F.

That would tend to setoff the CEL???

2007 F150,4.2V6,18K miles
Several weeks ago my truck started pinging very bad,esp. at upper rpms.I took it into my local Ford dealer and they diagnosed it as a bad EGR valve.They replaced it and reflashed the computer.Well,that didn't fix it.Back to the dealer it went.This time they wanted to replace the IMRC bushings.Upon removal of the upper plenum to get to the bushings the tech found anexcessive amount of oil and carbon lining the lower intake plenum walls.The spark plugs were oily and carboned too.Also,the pcv valve was dripping with oil.After decarboning the intakes and upper cylinders (4 times),replacing the plugs,replacing the MAF sensor,replacing the pcv valve and hoses,they said it was fixed.For about 3 days afterwards,it was ok; then this past week it started pinging again! This time the tech and I went for a ride with his laptop plugged into my computer to record whatwas happening when the enginestarted pinging.Ford engineering will go over the techs recordings and then give further instructions on what to do next,if anything! [sm=violin.gif]