hfm 3.5 questions concerns

[matt]

find a bosch part number somewhere on it?

[ericzz]

Anyway to test it to find out if it's the real deal ?

[matt]

120.00 shipped NIB . funny thing is I can not even find the auction on ebay of my feedback . The guy was in GA , he had a bunch of them now poof he is gone . Anyone know if the sensor is different or just the housing ?

Sensor and housing are both different.

[ericzz]

120.00 shipped NIB . funny thing is I can not even find the auction on ebay of my feedback . The guy was in GA , he had a bunch of them now poof he is gone . Anyone know if the sensor is different or just the housing ?

[Mike B.]

Things I would look at if I had knock (pinging) issues, in no particular order:

- Injectors functioning properly: delivering enough fuel? Sized properly?
- Plugs: Are they in good shape? Cracked insulators can be a source of pre-ignition. Are the the right temp range?
- Timing: what is the total advance vs. stock with your chip?
- Knock sensor: functioning properly?
- Dyno / Logging Wideband O2: I would be curious to see what my AFR's looked like.
- HFM: Doubt it's faulty since the stock size still leads to pinging.

[FredK]

How much did you pay for it? I don't think I've heard of a fake 540 HFM before!

[ericzz]

Ok many of you know I have been battling a ping issue . I had a thought could the EBAY 3.5 hfm I bought on ebay NIB for a 1/3 of the price of others be a bootleg or a regular one with only a larger housing . I just swapped a stock size s50 unit into the car and took it for a ride and I have noticed no difference in the cars performance or the Pinging . I removed the sensor itself from the housing on the 3.5 and it has no numbers on it to verify . Would this cause a ping if it truly is a regular one in a large body ? Would you try the real thing to rule this ? out . THANKS !