Discussion and questions related to the course EFI Wiring Fundamentals
would there be any down side to using an absolute pressure sensor for oil and coolant pressure? apart from loosing 14.7psi off the maximum?
absolutes are available locally in 1/8npt.
otherwise i will just need to run a 1/4 to 1/8 adapter witht he below:
cheaper sensor at least to offset the cost of the adapter.
No, will be fine except for the slight loss of range you've mentioned :-).
The first sensor you've linked has a silicone seal (PX3AN2BS100PAAAX)
We use stainless steel AEM pressure sensors on about everything. I'm sure they are re-branded with AEM stickers. Many years ago we used the AEM brass sensors but kept seeing the sensors fail over time and from that point on switched over to the stainless steel sensors and never had a problem. Almost every customer car I install oil pressure, fuel pressure and map sensor all stainless steel sensors. I average 2-3 cars a week with this setup.
ordered 2 off PX3AN1BH010BSAAX. from RS for $45 each delivered.
will report back when i have ran them (coolant and oil pressure, i run ethanol fuel so these cannot be used for fuel pressure. will need some MLH for fuel pressure), i realise they are 1/4" npt which will require an adapter to suit my flexible lines but in stock and cheap is hard to resist.
Good man, I look forward to hearing how they go.
I've used el-cheapo sensors from Aliexpress before, and compared them back to back with some Honeywell MLH sensors and any error was within 0.1%... However I wouldn't trust them to remain reliable!
I did some research the other day and decided the MLH was the way to go for E85 and oil. Particularly this model https://www.digikey.co.nz/product-detail/en/honeywell-sensing-and-productivity-solutions/MLH150PGB06A/480-2579-ND/1248914
Found this very informative comparison sheet somewhere online.
why did you go vented gauge (relative)?
That's how I understood Fuel/Oil pressure is measured. Absolute is generally only used for Manifold pressure.
Done some more reading; looks like you are right Josh. Sealed Guage would be the one to go for (wouldn;t be affected by engine bay temperature and if there was an overpressure event and the diaphragm failed, you would have an extra barrier stopping a fuel/oil leak)
Zac, how about a webinar about temperature and pressure sensors to clear this up?
Have thrown it into the webinar requests log we've got here, its an interesting topic for sure. I like to use sealed gauge senders where possible, as I dont want that signal moving around in relation to atmospheric pressure and temperature, as these correction factors are usually taken care of in other parts of the tuning process.
Sorry for dragging up an old thread.
I was just about to order the ones with the silicone but I see there are two materials there silicone and HNBR.
Is the HNBR suitable for oil and fuel?