Dashhawk AFR Monitoring

DaleNixon

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2001 Miata, 2011 Mazda 2
Apologies if this has already been covered. I've been logging a bit of data with my Dashhawk and trying to keep an eye on my AFR.

My car seems obsessed with keeping the AFR at 14.69:1 for idling and cruising. I've seen it go as rich as 10.10:1 during hard acceleration/boost.

Out of 7 logs I ran I did see a small bit of knock retard for a brief moment in one. One registered at 0.4 and one was at 0.7.

I'm pretty sure my stock BPV is leaking as I wasn't able to break even 15PSI under full throttle (not even a spike that high). I'll post some logs in this thread later. I plan to remedy that with a Forge BPV anyway.

I guess the point of this thread is that I've recently installed my HKS SRI and would like to know what would be recommended parameters to log and keep an eye on to make sure my car isn't running too lean and/or experiencing excessive knock. What AFR's should I keep an eye out for under what conditions? Thanks.

Edit: I haven't seen any CEL's or anything; I'm just trying to mod responsibly.
 
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My car seems obsessed with keeping the AFR at 14.69:1 for idling and cruising.

All cars run 14.7:1 at idle and cruise - most efficient for catalyst. At low speeds (rpms) and load there isn't a threat of pre-detonation. Cylinder temps and pressures are low

I've seen it go as rich as 10.10:1 during hard acceleration/boost.

Don't see too many wideband's in stock systems. Usually ECUs go open loop at WOT - so unless we have a wideband o2 sensor, I wouldn't trust that. But this also isn't the first post that I've seen people referring to the stock O2 sensor as wideband.
 
Yeah, the MS3 comes with a wideband O2 meter, stock.

I have my Dashhawk to view the following PID's:

- Intake Air Temp
- Boosted Air Temp
- Knock Retard
- Engine Load
- AFR
- DI Fuel Pressure

I've also got alarms set for Knock Retard at 1*, 2* & 3*

Just what I'm paying most attention to right now. IMO, the DI fuel pressure is going to be more important to watch under WOT, as any pressure drops below 1600 psi is going to lead to a lean condition.

Couple of things that I noticed. I definitely get random Knock Retard on heavy throttle, but usually around 1.1* or so. Nothing major (not that I'm not looking to eliminate it). However, I have gotten much more significant Knock Retard when the Boosted Air Temps are > 150* or so (heat soaked). Highest that I've seen in those instances was 5.4*, which IMO is an issue!

Typically, my Boosted temps will be @ 100-110 when I'm cruising, but in heavy traffic, I've gotten as high as 160*. Worse, if I park for a few minutes, then get back on the road, I've seen intake temps as high as 180 degrees! The b**** knocks like crazy when that happens! I really need to get rid of this damn stock IC...

Just my .02 cents BTW...
 
Your AFRs are plenty rich for a 10.10 ratio. Really anything above 12.5 I would freak out about...but stock cars usually don't ever go that low at WOT. When I was stock, mine went as rich at 9.3 or so...

After I tuned mine, it now flat lines at 12.0!!!! (2thumbs)

The only three things you really need to worry about with this engine is DI Fuel Pressure, AFRs, and Knock Retard. Everything else is pretty much out of your control...

Make sure you got fuel, that your mixture is ideal, with no knock...

Oh and anything under 1.0 of knock is OK...nothing to worry about. Over 2.0 (really 1.0) I would lift off the throttle. Set your DH to alert you at anything above 1.0 or 2.0...
 
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I haven't found any PID for monitoring Knock. All I see is a Timing ADV PID under Spark/ignition. Where can I find this PID. Sorry for ressurecting this thread.
 
I haven't found any PID for monitoring Knock. All I see is a Timing ADV PID under Spark/ignition. Where can I find this PID. Sorry for ressurecting this thread.

Actually, this is better than starting a new one! :D

Check under Mazda specific PID's; under spark; it's called "spark knock retard". If you don't see it, you might need to go to the most recent version of the dashhawk software...
 
Alright...I have the latest software update, now were can I get the drivers to install on the computer so the computer and dashhawk can communicate to each other. Usually when you connect a USB device, it will install drivers, but my computer cannot find any on the device.
 

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