I recently installed a PFC, and I've been thinking of getting rid of my boost and water temp gauges and just getting those readings off the PFC commander. I wanted to know what your opinions are about doing that?

I'm concerned about visibility, whether it's to annoying to read off the commander. And also gauge accuracy, idk if the PFC or the gauges would be more accurate. If it's simply better to use regular gauges I'll just keep using them, otherwise I'd like to clean up the interior and just have what's necessary.

 

Many people usually get rid of their Water temp and keep their boost. Each have their opinion on this. I personally would like to keep the boost for better viewing and diagnostic. As for water temp, I only check it to make sure the engine is warmed and hot before I drive it off or boosting it.

-AzEKnightz

 

I have deleted all aftermarket gauges on my car except wideband. Set the PFC Commander to monitor in 1 or 2 channel and it will be easier to see. You may also want to look into the new Commander screens which are supposed to be much easier to read.

One thing though: if you have a stock MAP sensor with the stock calibration, the PFC will read boost a little low. The water temperature reading should be fine but the sensors do lose accuracy if they are original and can read too high/too low. A new sensor isn't that expensive.

 

The Commander is a PITA to read most days, impossible when the sun is just right. I keep both those perameters displayed, but mostly for peak values.
The only aftermarket gauges I have are boost and temp and I kept both. Can't imagine deleting them. Readable under all conditions and the analogue is easy for me to glance at. And the boost is also in line of sight of my tach.
If Apex'i ever re-designed the commander display....maybe. But until then I like my gauges.

 

^ Commander was redesigned to EL and now has a much better screen. Check it out

 

The New commanders look legit, they match the stock 93 dash lights s well, easy to read, and adjust... I just wish they could update the PFC to have a few more modern features... either way, always a good buy....


I use my PFC to watch boost and water temp right now, I want a separate boost boost gauge (soon enough) and few others, but for now, it works...

just make sure the screen is in good line of sight


J.

 

most of the time you are only looking for peak value anyway

 

No I'm not. Primary boost, vacuum, temps at cruise, temps after hard boost, temps at idle etc.
Maybe it's a generational thing...I'm old(er) and just prefer the analogue gauges.

I'll definitely check out the new commander though. Not sure how I missed a re-design.

 

I have a boost gauge but I use the PFC for water temps. It's saved my *** a couple of times in 3 years when I ripped up the radiator hoses.

 

video of the new Commander:

http://www.youtube.com/watch?v=jRcvmFWVk-8

 

It seems as the new commander would be worth the investment if it's going to be the primary display.

So for now I think I'm going to end up removing my water temp gauge but leave the boost gauge. What I want monitored is water temp, boost, and wideband. And I want to mount them on a dash pod. So the AFR gauge is a must, and I guess the other gauge I would use is the boost gauge, and I would read water temp off the PFC.

 

When I had my powerfc I saw a difference of up to 10 deg between it and my Autometer. The Autometer sensor was put in the stock water temp location on the rear iron. It seemed to be more accurate than the PFC.

 

which sensor (and where) does the PFC take its coolant temp reading off of.... I know the stock location is the rear iron (as posted above) I have also seen a significant difference in what the PFC reads and the rear iron sensor..


J.

 

I'm gonna have to check the differences in readings better. Perhaps like arghx said, if you're still on the original water temp gauge, it could lose it's accuracy and give wrong readings.

 

I use both the Commander and an aftermarket water temp gauge. The PFC sensor on mine still comes from the rear iron, and the water temp gauge comes from the top rad hose, so you can see the temperature accurately at two distinct points in the system, often up to ~10 degreees C apart, which is helpful diagnosing any problems.

Most importantly, with an analogue gauge you can see at a split second glance not only the approximate reading, but also in which direction its moving (ie climbing suddenly, which is obviously bad). With a numeric readout like the Commander, you have to look, read, let your brain translate the numbers and work out whether they're increasing or decreasing and then let your conscious mind in on the secret. This is why aircraft still use analogue readouts, its the quickest way to assimilate information for the pilot.

Finally, the new Commanders illumination is great, but the old skool LED ones are crap. Any hot sunny day and you just get the "Black Block Of Death" where the whole screen overheats and turns into a huge black square making it really hard to read anything. Since I believe Miami tends towards being a bit warm, maybe worth bearing in mind lol

 

the pfc reads water temp off the thermosensor at the water pump housing, the coolant right there is a little bit cooler than it is by the time it reaches the rear iron(more accurate temp reading location).

the rear iron sensor is used for the dash gauge ONLY.

 

I've seen at least 3 original OEM water temperature sensors (2 wire sensor on back of waterpump housing) read "off" compared to a trustworthy aftermarket gauge. One read a little low, one read very low, and one read very high. In all three cases a brand new OEM sensor fixed it immediately.

Whether you are using the Commander as a temperature gauge or not, it is important to check and/or replace the water thermosensor on any car. This sensor's reading is used to affect cranking fuel, cold engine idle speed control logic, cold engine fuel enrichment, cold engine ignition retard, cooling fan control, hot engine fuel enrichment, and hot engine ignition retard. If the sensor is off it can have a noticeable effect on driveability and even engine safety, depending on whether it is reading too warm or too cold and how far it is actually off. For example, if it is reading 20C too cold you are going to be wasting fuel during cranking and warmup, and your hot engine ignition retard table will be for the most part ineffective.

 

Whree to get, and how much?

What holder is that?

 

I don't understand why folks don't use the stock water temp gauge with the "lineralization" mod. It works great and you can use the PFC to adjust the pot in the circuit to put the stock gauge needle where you want it at normal operating temp. It also allow you to adjust if your sender is a little high or low.

I have the instructions for the mod (I am not the author). Too big to upload. PM me if you want a copy.

arghx - I don't think that the temp thermosensor you cautioned about is in the Fan Circuit. The fan switch is a seperete sensor that most replace with the one from a S5 second gen. They are both next to each other in the back of the water pump housing.

 

Also why I think the throttle-body coolant line is a good source for real-time accurate readings. It takes them right after the coolant has passed the combustion chambers of both housings. It also explains why, especially during warm-up, my gauge responds marginally quicker than the PFC.

 

The #2 and #4 fan relays are triggered by the ECU, whether it's the stock computer or a PFC. The ECU switches them on based on the water temperature signal from the thermosensor in the water pump housing. The ECU controls one of the three fan speed "steps." The other two are controlled by the A/C circuit and the fan thermoswitch.


See Dale's thread or my thread: https://www.rx7club.com/3rd-generation-specific-1993-2002-16/why-engine-so-damn-complicated-part-3-cooling-fan-controls-876767/

The ECU's temperature reading is in some ways the most important because it is a factor in calculating fuel, timing, idle control, and fan control.

 

Bad news on the new commander. It retails for $350. The cheapest I have seen is $315.

 

^That's about what I saw them for too.
With my gauges it's not real high on priorities at that price, but they do look really nice. Maybe in the spring.

 

ewww.

There should be a upgrade discount.

 

There was a GB. Price was $300.