Well, I finally ended the anoying spark knock from my 2004 4.0 SOHC. I had tried new plugs, new air filter, cleaning the MAF, even SeaFoaming the engine. Nothing helped at all. I noticed a TSB for the 4.0 in regards to spark knock.... The soultion was a computer program update. I took it in to Ford today and they updated it. Fixed!!! It's like driving a new truck. It even seems to have more power at lower RPMs! Before, it would always knock on the highway (60-75mph) when going up any sort of hill. Not a bit now! I'm so excited and I hope this helps some other that are facing this problem.
Chris

 

My wife's '05 Merc Montego had a similar issue/resolution.

With all the computer controlled adjustments in vehicles these days, I bet we will see more solutions being fixed by updating the programming instead of turning bolts. Welcome to the end of the era of shadetree mechanics rebuilding their own vehicles.

 

More like Welcome to the next generation of shadetree mechanics.
With kids starting into computers at such an earlier age , it's just a matter of time before they figure how to write their own complete code for engine management.Probably running direct from a laptop and ditching the PCM altogether.

 

What did it cost you to have ford do this? my 2001 always pings when taking off from a dead stop or going up inclines and when towing my boat.

 

rangers have computer updates that need to be done? i have a 02 that i know never had this done. should it be something that i look into?

 

I don't think they all need to be updated, there happened to be a TSB for the '04 4.0 engines.
As far as price, it was $95 for a diagnosis and another $75 to flash the computer. It was well worth it to me to not have the pinging and to be able to run 87 octane fuel again.

 

hmm this could explain the miss in my 04 4.0. ill have to check into this but aint no way in hell i am gonna pay that price.

 

The price on my wife's Montego was ~$84 after taxes. There are several TSBs for the '05 and early '06 Montego/500/Freestyle with a PCM update as the solution. The TSB issues include hard shifts on the six-speed auto, RPM wandering while cruising on the CVT, headlight flicker, hard start/extended crank in cold weather (our issue), and bad breath (j/k). We did see a minor improvement in fuel efficiency after the update.

But will they run Windows, Mac, or Linux on the vehicles? Seriously though, you can get scan gauges that run from a laptop now. They are only capturing data, though, not setting shift points, etc.

You will have to see if there are any TSB's on '02s where updating the PCM is a solution. If not, you may still want to consider it, as there might be fuel efficiency (my experience) or power gains (OP's experience) from the engineers refining the logic.

 

I have a 2000 Ranger 3.0 Flex that's been pinging ever since I got it when I run Reg. If I run E85 it doesn't ping and today I put in 89 octane and no ping. I'd like to run 87 though as I drive a lot. Truck has 161K mi.

 

Does the 04 Ranger have an EGR system? If not, the timing is a lot more critical compared to engines with the EGR system. I had an 89 Ranger with the 2.9L engine. It had no EGR system and on very hot, dry days it would tend to ping. I didn't want not retard the timing and just took it easier on hot, dry days.

 

I had my 2010 flashed for being sluggish.