Jozsi55

Hi All,

I kindly ask your advise: After replacing Knock Sensor (that was suspected), but I still ha the problem:
When I stop the engine for a few (2-4) minutes only (for a sample at railway crossing) and I do not pull out the starting key, I sit in the car, the radio is on. After that, when I start the engine I experience, that the care is do not speed up so quickly as before and also I can hear the sound (from exhaust pipe) the tone is more deeper and louder.

In recent days, as we had a hot weather now (~30C), the problem arose at traffic jam. Only after getting out from that and passing around 10 km, came back the normal engine behavior. (The fun is working, the temperature meter was just a bit over the middle of the scale)

When I was watching the engine (thinking what could be the problem) I noticed a strange thing on the box of the engine control electronic: an additional aluminum plate is stick on it. Might it was damaged ... and with that plate was repaired. ?? My question is: If I were bought a second-hand control unite (module), (there are several with very same type number on eBay). Could I use it? Can it be used in a different car? (I mean: are it protected by code or not?) What impact can be expected? (Of course I suppose it's faultless)

Thanks for your feedback in advance:
BR: Jozsi55

Nuke

Without some more details, it sounds a bit like a fuel related issue. I don't know what the quality of the fuel is like in Hungary. I would try running some fuel system cleaner. Be sure to follow the directions on the bottle for the proper amount to use in your 16 gallon fuel tank. You may need to run 2 treated tanks before you see any results. If that doesn't cure the problem, let us know.

It also wouldn't hurt to replace the fuel and air filters. I would NOT attempt replacing the PCM at this point.

2005Redfire6

The deeper and louder sound makes me think you're describing the motor bogging. Like Rick mentioned I would try to replace the fuel filter first and foremost.

Jozsi55

Hi Rick,
Thanks for your recommendation, I'll replace the fuel filter. Regarding to fuel cleanness is not a real problem in Hungary, but newer know... We have Europe standard Fuel Companies and also many international ones, like Shell, Agip, OMV...
But there is an another problem: for the Mustang the (R+M)/2 octane rating of 87 fuel is recommended, but we have 95 or higher only. It's true the USA standard and the Europe standard is a bit different, the USA 87 octane is roughly equals to Europe 91, but that already phased out. So I can to use the 95. I hope not this cause the problem and the PCM unit is able to adjust accordingly...
I'll let you know about the changes after the fuel filter replacement.
bye: Jozsi (Joe)

Jozsi55

Hi Eddie,
Thanks for you too the proposals. Might you can see as I wrote to Rick, I'll replace the fuel filter.... I hope, it helps.
Bye: Jozsef (Joe)

2005Redfire6

Higher octane shouldn't hurt the car being able to run 87 from the factory. It usually causes issues when tuned to run higher octane and lower is used.

Nuke

Eddie is correct; running higher octane than what the car is tuned for won't hurt the engine but also won't add any performance over what the tune is calling for. Your PCM will not adjust to make use of the higher octane unless it's retuned.

I'd still run some fuel system cleaner. SeaFoam is my preferred product if I suspect an issue. Techron is what I use every 10,000 miles or so.

Jozsi55

Hi Rick and Eddie,

It seems the fuel filter replacement solved the problem. Thanks a lot!

Regards: Joe

Nuke

Superb.