SDL with new hyperflows, new rear o2 sensors, changed oil and reinstalled right temp

Good.

 

I have noticed this problem too with new TC vs old TC since I monitor EGT manually bypassing TCU's completely. What we need is the graph of voltage output vs. temperature. I bet that 0.5V is a significant variation on temperature. In the docs for this system you posted before I can't remember if there was such a graph.

 

Referenced to 32 F as 0 V, 2.2 V would be about 1032 F, 2.7 V about 1260 F. (0.0022 V/F)

 

That's what I thought. So new TC to Old TC there is a 200*F spread. Interestingly I have that issue right now with my manual monitoring but only a 100*F spread. I think TC aging is an important issue because this aging cuts the window down before the TCU's trigger SDL and limpmode. We will see operational ranges of 1400-1000*F and a 200*F ageing delta is significant.

It seems that all K type TC's are the same. Do you know a way or different robust K TC's like milspec or FAA certified or something to ensure consistent TC outputs? I think we would benefit from reliable inputs.

 

If it's aging the only thing that can be done is better shielding. But ultimately the wire composition and crystal structure change over repeated heat cycles leading to inaccuracy. But I don't know if this could account for a 200 degree F variation.

 

Well, all I know is that we spent another trouble free day in my 95 today. About 150 miles running around northeast CT with a lunch stop ant one of my favorite pubs.

 

You gotta love M.Y. 1995! Before my recent major service, my 1995 F355 Challenge would get a CHECK ENGINE 1-4 light if it idled for more than 30 seconds. It went off soon after picking up speed. Now both CHECK ENGINE 1-4 and 5-8 lights come on and go off within a second of each other with the same maneuver.

My car is working perfectly!!

 

I did get a couple of 1-4 flickers earlier this year. Code said O2 sensor. Ordered one from Rock Auto for $63. Not so much as a blink since I put the new one in. I have a hard time calling replacing an O2 sensor a problem. I had to replace one on my Toyota truck and it cost almost twice as much as the 355 sensor. I guess my 355 is as reliable as my Toyota. The Toyota unit was also from Rock Auto. It was cheaper to fix my 355 than my Toyota pickup. See 355s are not expensive to maintain.

Oh, and yea, what is that TC doing in the by pass loop on an OBD car? 95's don't have it.

 

It simply looks for a temperature when the bypass should be open. To tell if the bypass is working correctly or the cat in the bypass pipe is OK as the post cat TC's do to tell you the big cats are working.

"emission controls"

 

If any part of the emission catalyst monitoring system shows an over heat mode it will throw a SDL putting it into a limp mode. If any part stays out of perimeter it will throw a CEL stating the Emission System is malfunctioning, check it

After the engine gets to 163 degrees the fuel trim runs off the 02 sensors
Load vs coolant temp vs throttle position vs rpm vs coolant temp triggers the fuel trim amounts. Did I say coolant temp? That seems to be all over for calculations and a very important thing you have a most excellent cooling sensor and connections


Were still mapping the ECU, at this time it appears
These two seem to be on separate circuits.

Now what did I say? LOL

 

Bob,why can't you get the proper nut from the TC manufacture? Drilling out an existing thread and re-tapping a different thread over it is less than ideal, and depending on the existing thread, it might not be possible.

EDIT - I meant compression cap - not nut.

 

I'm not understanding, Bob. You mention nut is correct but need to tap compression cap - can you post a picture please?

 

OK, I was confused because you stated above: "and the nut has the correct thread to fit the cat thermocouple fitting on 355s and 550s." Then you stated you needed to drill and tap it.

If I'm missing something, let me know.

 

If the need was high enough, we could bang out 100 or 200 of the nuts in my shop for a pretty affordable price and then they would not need alteration and the plating would not get cut away from tapping them. Even better, we could make them from stainless steel so not plating would be required.

 

That's good.