Do the vulcan 3.0L engines have knock sensors? I was under the impression that all 3.0Ls come equipped with them, but now I'm reading where only the duratec engines have them. Anyone know for sure?

 

Hey rock.
I just check the EEC codes for the Ranger. Pre 94 has a code for the knock sensor. 95 adn newer don't. I am not sure if this helps or hinders. LOL.

 

Hey saint,

What you say is a start, and seems to support the "no knock sensor" proposition. I also heard that the sensors were "discontinued" on the Vulcan sometime in the mid 90s, which is consistent with what you found regarding the lack of knock sensor DTCs after '94.

Also, I just looked at Haynes for my '97 Taurus (3.0L Vulcan) and it specifically references the knock sensor as being used only on the OHC Duretec.

If it turns out to be true....no knock sensor on mid 90s+ Vulcans... then I have to wonder why the heck that would be? Especially with all the talk you hear about pinging in the Vulcan.

 

Your above and beyond my basic mechanical knowledge rock. I know where to look for knock sensors. But I have no idea what one actually does. Fill me in rock. Knowledge is power.

 

Hang in there and I'll post something soon.....

 

The knock sensor listens for pinging and sends a signal to the PCM when it occurs.

 

Hi Ken,

Just to add a little more.....The PCM will advance the timing to the
point of pinging, then back it off (retard) it a little. This is a constant, dynamic thing. With this kind of system, you will actually
pick up some performance by using a higher octane fuel. Most
of the European manufacturers (Saab, Volvo, VW, etc.) with
turbochargers have this type of system....In addition to timing,
the knock sensor will also determine the amount of boost
pressure.

 

Bob and Ken, glad to have you guys join the discussion! What you said about knock sensors and the way they work with the computer to combat pinging is good stuff.

Although its aimed little more toward high performance engines, here is a good article on the subject: Knock Retard

Also, here is a nice little 2 page PDF Article on knock sensors and what they do. Contains a few neat sketches and graphs, too: Knock Sensors

The question still remains in my head....why wouldn't Ford use knock sensors on the current generation of Vulcans which are known to ping?

 

Hey Rock,
Maybe they figured out how hard it was to get rid of the ping before we did. LOL. "Hey guys this pinging keeps messing up the knock sensor......" I can see he engineers grinning from here. LOL

Hey Ken and Bob thanks for the insight. Always glad to have expert opinions.

 

lol...so they left it to guys like us to figure out (on our own nickle) ....and it wouldn't surprise me to find out that some people around here (not including myself) might very well know more about how to fight pinging in the 3.0L Vulcan than the people who designed it!

 

Knowing how Ford does things I'd bet they got rid of the knock sensors to save money. With a little different programming of the PCM such as more EGR flow, less timing etc they are able to keep it from pinging without the extra sensor. The newer engine controls are more accurate than the older ones. With more accurate MAF readings etc they are better able to manage the fuel and timing curves.

 

Been looking in to this for a while. With 9.3:1 compression, the Vulcan leads the pack in compression ratio for Ford OHV engines. There hasn't been a ratio that high in years. I think that is the main issue.
Couple that with the 14lb injector thing and we are bound to ping.
The '94 ECU has an unused pin 23 labeled KS in the Ford Diagrams. Yep, Knock Sensor. My guess, it pinged regularly, they could not get it to run in the prescribed timing (for smog/efficiency), so they dropped the sensor (which the ECU sees as "all's well, keep the full timing!"). I would like to add the sensor and get it going. The 8.0"1 compression supercharged engine I'm building would love it.

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