Found this under the hood of the Ratty Tundra. Not sure what it is. Mechanic buddy thinks it is some kind of dealer-finance department tracking device. Anybody want to venture a guess? It's the device on the MAF meter between the air filter and the intake.
It's wired to a relay in the top right corner of this fuse box (edit: starter relay) with the fuse box cover notched - and a power lead out the side and across the top of the engine.
This is how the connector splices into the airbox (edit: IAT) sensor.
Gray loom is Toyota. The black loom with the jumper harness is "mystery device".
wae
SuperDork
5/15/18 6:38 p.m.
It's not something to somehow fiddle with the MAF signal, is it? Or is that hooked up to a IAT?
Here is another photo from the windshield side. Power comes to this device that's glued on the back of this box between the air filter and the intake. (Edit: the uh, MAF meter)
Then the wires run across and splice into the IAT sensor wiring.
The factory IAT sensor wire runs underneath this device on the side if the MAF sensor in this photo.
Factory Service Manual identifies the relay as the ST (starter) relay.
I unplugged the mystery device (but not the power wire) and re-connected the original IAT sensor wire, and the truck started up just fine.
So I'm still puzzled about what the extra contraption does/did. It doesn't seem big enough be a GPS tracker like a buy-here-pay-here lot might install (in my imagination anyway - I have no real basis for saying that.. but the device is small).
Part of a removed alarm system?
In reply to Dr. Hess: maybe.
I just got it and the only previous owner died. The Carfax has a bunch of entries that only say "tuneup" or oil and filter change, so all I have.. is a mystery.
I think its one of those Ebay universal ECU chips that basically makes the IAT read low to dump extra fuel, or may clamp the MAF signal or something equally inane.
Certainly wont hurt to deep 6 it - quality install for sure.
93gsxturbo said:
I think its one of those Ebay universal ECU chips that basically makes the IAT read low to dump extra fuel, or may clamp the MAF signal or something equally inane.
Certainly wont hurt to deep 6 it - quality install for sure.
Any idea what those are called?
Now I'm more curious to see how the truck re-adjusts to having that disconnected. Also curious how that little device interacted with the MAF - if at all... It seems to be glued in place and I didn't really want to break it.
Edit: nevermind. Dr Hess may have nailed this.
93gsxturbo said:
I think its one of those Ebay universal ECU chips that basically makes the IAT read low to dump extra fuel, or may clamp the MAF signal or something equally inane.
Certainly wont hurt to deep 6 it - quality install for sure.
I agree.
Edit: which on further review makes us both wrong.
I did find one emissions test failure on the Carfax. This may have been the "fix"....
WilD
Dork
5/16/18 8:34 a.m.
Does it have aftermarket exhaust? My only experience with air injection is from motorcycles, and it's removal eliminates truly obnoxious popping when you put louder muflers on your Triumph...
Dr. Hess said:
Your Google-Fu is weak.
https://www.ebay.com/itm/Toyota-Lexus-05-07-2-7L-Secondary-Air-Injection-System-Bypass-Kit-Plug-Play-/232020772972
What is the purpose of that lil guy? I mean - I get the big picture. Why is it installed?
Seems the purpose is to defeat a broken secondary air system (emissions voodoo) to pass emissions tests. Linky
Last night, unhooking it appeared to do nothing at all. Today after work I was greeted with a check engine light. And a sincere hope that the "off-road only" parts on my less ratty truck don't butt berkeley me (next May) when I have to go for emissions testing.
So it will stay! Thankfully, re-connecting the device and disconnecting the battery to reset the ECU successfully removed the CEL.
Dr. Hess said:
Your Google-Fu is weak.
https://www.ebay.com/itm/Toyota-Lexus-05-07-2-7L-Secondary-Air-Injection-System-Bypass-Kit-Plug-Play-/232020772972
Clearly my description wasn't. I'm baffled, amazed and pleased that you were able to track this down!
This place is unreal.
I just googled up the numbers scratched on the top of the thing and "Toyota". Easy-Peasy.
