VH45DE KS life?

[maxnix]

OK, I have a standard G50 no TCS no CA car with NICO Stage 1 ECU.

Got down to my knock sensors to replace them and they look like new! OHM test at 552K and 554K through the harness.

Am I wasting time replacing them?

At the very least, I will keep them for back up.

Dennis, any comments? Do piezoelectric transducers age and decline in sensitivity, or do they simply abruptly fail after so many cycles?

[qship96]

I would imagine the plastic housings become brittle with age and constant heat cycles, eventually cracking and becoming non functional. Might as well replace if plenum is still off and Joe is offering them at 1/2 price. Are you replacing all hoses? The ultimate kit includes KS/harness/ALL hoses for $855.

[maxnix]

Yeah, every damn thing, although I think everything below the lower runners could go at least another 5 years, minimum.

The only way to tell the old from the new KS is the slight wear on the metal washer like surface from tightening them into the block.

Oh well, overkill is us!

[SteveTheTech]

If the resistance value is still within tolerance and the sensor and circuit are in good visual condition, both the casing and the harness contacts are clean and show no sign of corrosion. I would say there is no need to replace them,I would not personally recommend one of my customers buy them in that condition. I don't think the labor involved would be justified by my customers, I try not to recommend things I would not replace on my own car. However, if you are pulling the plenum for some other reason and you have the parts, it couldn't hurt. I really do not know how to deal with something like that, I do not think I have ever experienced someone who wants to replace their KSs.....

I too wonder what Dennis' opinion on this is.

My dealer charges so much in hourly labor that we rarely have people want to invest the money in their cars anymore. Well that's until the market tanked, then no one spends money on anything and some cars are starting to fall into disrepair or the work is performed with inferior parts and labor just to save a few bucks.

[qship96]

Brian, the only thing I can tell you is that my Q has never overheated, but the knockers went out at about 190K and were replaced at about 200K by T3- so that leads me to believe that the plastic ages due to normal underplenum heat/cool cycles- 11 years and they had fatigued and failed.Seems if you dont want to risk diving in again for another 100K, safer to swap now while it is opened up.

[maxnix]

I appreciate the information. I would think these could easily go till 190K as the sides are pliable, no hardening, no corrosion. Like I say, virtually indistinguishable from new save where they seated to the block. And on a Texas car too. Lots of intense heat cycles.

But I will replace the KS and the harness and set them aside for when they are no longer made, I guess. Thanks for the information.

It's getting kind of scary with people skipping brake jobs and using used tires out there.

[Q451990]

I replaced mine in September during my under plenum work. They ohmed fine, no codes, but the cases were cracked. That was at about 91K and 18 years in service. No known overheats...

I wonder if there is a difference in temperatures in the "valley" between the grilled G50 vs' the earlier ones?

Heath

[maxnix]

I wonder if there is a difference in temperatures in the "valley" between the grilled G50 vs' the earlier ones?

Heath

I wonder if the later grilled G50 operate cooler, because I doubt the materials on the later ones were improved substantially. Almost all my hoses are about 25% through their life cycle. Coolant has been kept fresh, though.

Thermostat was in great shape. Have to test it operationally later. Always indicated a little above midway.

[qship96]

Is this the first time the plenum has been off? Wondering why you chose to dive under if your knockers are ok?

[maxnix]

Yes. Want the 10 year service interval. VC gaskets are easier to do, and I didn't know the condition of the hoses off the Y at the bottom.

I'll probably have a walker by then anyway!