Fan switch sensor removal??? (Page 3/3)
Skybax OCT 12, 04:48 PM

quote
Originally posted by fierofool:

I wholly agree with Patrick on using the 195 thermostat. It allows the engine to run in its proper temp range and go into closed loop. In open loop the ecm is feeding a much richer fuel mixture.




That's a popular misconception, with 180 stat the engine still runs at proper temps, the system only in OPEN LOOP until following:

1) The O2 sensor has a varying voltage output, showing that it is hot (600 degrees F) enough to operate properly.
2) The coolant sensor is above a specified temperature for CLOSED LOOP (usually 135 to 150 degrees F).
3) A specific amount of time has elapsed after starting the engine (usually 2.5 minutes).

Like I mentioned in my original post above, there is very little difference between 180 and 195 stat...

1) The 180 stat will open a little sooner than 195 after its in CLOSED LOOP (150).
2) While it opens at 180 temp, it will only run "slightly cooler" operating temps (190 to 200 in summer, 185 to 195 spring/fall) under normal driving conditions.
3) Engine runs only "slightly richer" which is exactly what I want on my 36 year old engine with 80k carbon on combustion components (acts like sponge).

NOTE: Engine temps will climb in hot summer weather sitting at red light regardless if you have 195 or 180 stat, that's when 210 fan switch kicks fans on at 215 and turn off at 205 instead of the factory 235 switch, which again is exactly what I want on my 36 year old engine with 36 year old head gaskets. In regards to the 210 fan switch bottom portion being larger in the coolant passage than original 235 switch, there is still plenty of room/flow around it, somebody posted a photo 18 years ago but its probably in the black hole of the internet now.

I was an engine tune-up technician for all makes and models in the 80's when you had points/condenser, computerized carburetion, and modern SFI/DI systems all on the road at the same time (the only decade in over 100 years of automobiles to have that triple combo). That was my full-time occupation 60 hours a week, setting up engines to run optimal (using those old SUN Engine Analyzers) to maximize performance and fuel economy (job title: Engine Performance Specialist). The 3 GT's that I've personally owned including my current one are all meticulously tuned to perfection to high standards, and they all run better than new averaging 22 mpg on hilly suburban/country roads with lots of shifting and stop signs/lights and all run 180 stats (86 GT V6 4-sp originally rated at 17 mpg city and 24 mpg hwy) so it is impossible for all of them to be running too rich to provide those stellar results.

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PS: On a loosely related subject while I'm thinking about it, for those looking for insight/suggestions on optimal oil, I only run Valvoline Max Life "High-Mileage" Syn/Dino Blend 10w30 in my old original 2.8 V6 engine for many reasons (one of the best oils out there, check out bobistheoilguy)...

1) 10w30 is unaltered unlike 5w30 and 10w40
2) The 10w30 gives a little better protection for hot summer weather on older higher mileage engine
3) Valvoline Max Life "High Mileage" has the proper balanced higher phosphorus/zinc (600/800) ideal for Fiero 2.8 V6 flat tappet camshaft with catalytic convertor, because the "non-high-mileage" levels are too low. Older pre-1974 flat tappet camshaft engines without catalytic convertors (especially high performance) need closer to 1200/1400 ppm so popular oil choices are Brad Penn (PA green oil previously known at Kendall GT1 and now known as Penn Grade 1) or Valvoline VR1. But those 1200/1400 levels are too high/harmful for catalytic convertors and overkill for Fiero 2.8 V6 and most modern oil levels are too low, making the Valvoline Max Life "High-Mileage" Syn/Dino Blend 10w30 ideal for an old Fiero L44 V6. Specs... https://pqia.org/valvoline-...tic-blend-motor-oil/

I realize oil is heavily debated, so basic info above is just a friendly gift to Fiero owners who want good/correct oil for their old 2.8 V6 without 100 hours of research.

[This message has been edited by Skybax (edited 10-12-2021).]

Xenoblast OCT 12, 06:32 PM

quote
Originally posted by Skybax:

The 3 GT's that I've personally owned including my current one are all meticulously tuned to perfection to high standards, and they all run better than new averaging 22 mpg on hilly suburban/country roads with lots of shifting and stop signs/lights and all run 180 stats. (86 GT V6 4-sp originally rated at 17 mpg city and 24 mpg hwy

...

1) 10w30 is unaltered unlike 5w30 and 10w40




I run the 210 fan switch with the 195 stat and I get 21 mpg, which is me driving calmly to work in town and also shifting at 5k on mountain roads. Also with the 10w30 is unaltered, what do you mean by that? I run 5w30 and couldnt imagine running any thicker because my oil pressure gets up to 70 psi when cold. Of course my guage could be wrong

[This message has been edited by Xenoblast (edited 10-12-2021).]

fierofool OCT 12, 07:13 PM

quote
Originally posted by Skybax:


That's a popular misconception, with 180 stat the engine still runs at proper temps, the system only in OPEN LOOP until following:




When I installed a 180 in the 86SE with the crushed pipes, my fuel economy really dropped. It went back up with the 195 thermostat. Maybe It's just me.

pmbrunelle OCT 12, 08:13 PM
I like the 195 thermostat on the Fiero V6.

I tried a 180 thermostat, and at that temperature the engine seemed to need more accelerator pump, and was less eager to rev.

YMMV.
Patrick OCT 12, 09:10 PM

quote
Originally posted by Skybax:

That's a popular misconception...



I very much appreciate your very well written comment(s) on thermostats and oil ... but I still challenge you on your following statement, as you've got no feasible way of knowing.


quote
Originally posted by Skybax:

...most folks use a 180 stat with that 210 fan switch



Replace "most" with "many" and there's no issue.


Perhaps it's in cooler climates where the advantages are more readily experienced with a 195° thermostat over a 180° one.
Skybax OCT 12, 10:05 PM

quote
Originally posted by Xenoblast:

Also with the 10w30 is unaltered, what do you mean by that? I run 5w30 and couldnt imagine running any thicker because my oil pressure gets up to 70 psi when cold. Of course my guage could be wrong




Simple answer = less viscosity improvers and better high temperature high shear (HTHS).

Most Fiero's today are summer weekend hobby cars, not daily drivers that see winter use. 10w30 is good to 0 F on cold start, my non-heated attached garage never goes below 45 F in winter. With a 36 year old 2.8 engine known for rod bearing failures I'm more confident with the MaxLife 10w30 High-Mileage specs.

The specific oil needs for every engine is very different (original design, modifications, age, mileage, etc). My daily driver is a 2005 Ford 2.0 Duratech that uses whatever 5w20 is on sale. My 67 Mustang has a modified 289 with 300 horsepower that was built in 1983 with 9000 miles on it, so I use Valvoline 20w50 VR1 in it because that is the ideal oil for that specific engine... https://www.youtube.com/watch?v=EWw_BDJd8FI

Back to the Fiero 2.8 V6, you can spend hundreds of hours reading oil chemistry, its endless, here are just 2 quick examples...

https://bobistheoilguy.com/...344948/#post-5862959

https://bobistheoilguy.com/...w30-vs-10w30.336060/

Sorry to derail, oil is a very deep science, back to your regular scheduled programming...

[This message has been edited by Skybax (edited 10-12-2021).]

branger OCT 12, 11:05 PM
Good topic, wish parts were also more available in Canada.

[This message has been edited by branger (edited 10-12-2021).]