Oil temp measuring

[EagleMark]

Although I did successfully test what happens when you shut the engine down with the radiator cap off.

I've done that test too! I hate when that happens...

The rest is not good news though! Guess it better to have happened to you then someone trying this and finding it break off while in oil pan! So best way is going to be a stock sensor and another fitting, just like the Corvette did.

[dyeager535]

With the nose as long as it is, anyone aware of any adapters in 1/2" that will thread into the pan, and allow you to screw the sensor to it? All I can find are 1/2" NPT, but that obviously won't work. 1/2" to 9/16" would require less thread cutting on the sender. Not sure if there was enough diameter to cut them to 5/8" or not.

[dyeager535]

So I've got a two wire CTS turned down and tapped/threaded. Looking to probably change the oil soon. Not sure the sender is going to work (tapping went pretty poorly) but willing to try it.

Resistance specs are here: http://www.gearhead-efi.com/Fuel-Inj...ull=1#post6888

How much effort is it to get the 1227165/6E/APYP to "read" another CTS? Is it even possible?

I did a bit of research, but prior to 1990 it doesn't appear the F or Y body used an oil temp sender, so it appears there is no extra position that the wires can just be run to, must be some code changing required, if it's not a physical limitation?

Eventually I'll convert to the '730/727, which had oil temp in some apps, but if it's fairly easy to accomodate with the '165, I could at least report back what happens if someone can help out with the "code" portion of adding it to the '165.

[RobertISaar]

the 7165 appears to have 11 A/D channels...

ch# pin Function
0  D8   MAP2(51K to Gnd)
1  A6   IGNVOLT
2  D7   O2VOLT
3  C11  MAP(51K to Gnd)
4  C10  CTS(348/4K to 5V)
5  C13  TPS(220K to Gnd)
6  B2   PUMPVOLT
7  A9   DIAG(10K to 5V)
8  C12  MAT(1K to 5V)
9  B11  ESC(externally filtered)
10 B12  MAFVOLTS(1K to 5V)

as you can see.... not a lot to work with.

if you want to open the ECM up, then i assume D8 at the very least won't be used in many if any applications from the factory, you could remove the 51K resistor and put either a 348 or 4K ohm resistor on the sample circuit with the other end connected to 5V and have to only patch the code to read channel 0 every once in a while and apply the 348 or 4K normalization table used for the CTS on it and it will create a linear output, save it to a free RAM location, point the ALDL stream to use it and then you've got it.

[dyeager535]

So this will actually be a physical endeavor.

I think this may have to wait until I go to the '727. :(

[RobertISaar]

unless you send it out to somebody who's willing to mod it..... i've done it ~5 times on a 16149396 to make more useful channels.

as long as you pay for shipping here and back, i would do it for a couple bucks.

that's assuming you can afford to have it down for the ~week or so it would take to ship.

[dyeager535]

I appreciate the offer. Unfortunately funds of all types have pretty much dried up for me recently, at least in the near term.

Luckily I got most of the '727 conversion stuff already, hopefully I can do that for no additional cost. If I get the '727 going, I can sell off the '165 stuff to help make ends meet. "Luckily" I have some spare MAF stuff I can sell, if anyone even wants it anymore!

The '727 conversion is just going to take awhile to complete. I need the truck running in the meantime, so I'll have to wait until I've got a good block of time to start that swap. Was why I was hoping there was some software way to get the '165 working for the OTS. Oh well. I have a sneaking suspicion its going to leak anyway, but I will have to remember to test it as a drain plug when I dump the first quart in.

[RobertISaar]

the 7727 has a bunch of unused MAT style inputs, so you'll just need to use the MAT conversion table and it's pretty much plug and play.

[RobertISaar]

a thought occurs......

are you using the voltage based MAF or a frequency based one?

if you're using the frequency MAF, then channel 10 would actually work for you as-is, just need to use the MAT normalization table.

[dyeager535]

Sory, didn't see the reply before!

I'm assuming it's voltage based...I've not messed around with anything else, it's an '88 MAF AFAIK....in the .bin the tables are based on voltage, so that's where I get my assumption. Right or wrong?

a thought occurs......

are you using the voltage based MAF or a frequency based one?

if you're using the frequency MAF, then channel 10 would actually work for you as-is, just need to use the MAT normalization table.

[RobertISaar]

i know next to nothing about the early MAF stuff. i know some were low frequency, others were just an analog voltage.

which pin is it connected to on the ECM?

[dyeager535]

B12. Looks like that unfortunately kills that great idea, eh?

I really just need to swap it over to the '7727. :)

[RobertISaar]

yeah..... that would have opened up a nice option. oh well.

here is what the 7727/7730 style inputs look like with 7727/A1 pin descriptions. other masks will be similar:

Ch0  A/C Pressure                pin C21 (51K to G)
Ch1  Ignition +12V               pin B10 (N/A)
Ch2  O2                          pin A16 (N/A)
Ch3  MAP                         pin C22 (51K to G)
Ch4  Coolant Temp                pin C16 (348/4K to 5V)
Ch5  TPS                         pin C15 (220K to G)
Ch6  Fuel Pump Voltage           pin A20 (N/A)
Ch7  ALDL Diagnostic Pin B       pin B3  (10K to 5V)
Ch8  MAT                         pin C4  (1K to 5V)
Ch9  Mux Channel                 pin XXX (N/A)
Ch10 -------                     pin B9  (10K to 5V)
Mux Analog:
Ch0  EVRV EGR Position           pin C18 (220K to G)
Ch1  Coolant Level               pin C14 (348 to 5V)
Ch2  -------                     pin C19 (2K to 5V)
Ch3  Knock                       pin A11 (100/4.02K to 5V)
Ch4  -------                     pin A14 (1K to 5V)
Ch5  -------                     pin A5  (1K to 5V)
Ch6  -------                     pin XXX (N/A)
Ch7  -------                     pin A15 (???) seems to be missing components for amplifcation

as you can see, there are 16 available pins to use, with a lot of pullups.

[dyeager535]

Just to make sure I understand....since the '7727 was used in some applications with oil temperature sender, with the proper mask/bin there will be nothing more needed than to hook a wire up to the correct ECM connector pin based on how that vehicle (in this case a Corvette) was wired? Essentially plug and play?

[RobertISaar]

should be. might have to enable an option bit too, but i wouldn't expect anything more than that.