EDIT: Pics are on Page 3!


Ive just finished the 3.4 swap and It runs but wayyy to rich.
Pushes black smoke, missfires, backfires so I picked up an OBD2 reader and hooked it up.

Nothing..

Not one code was shown. There should atleast be a couple missfire codes and o2 sensor codes but WTF?

Any idea's why the OBD2 says everything is good!?!?

 

Do you have any vacuum leaks? After I did mine, it ran like a small block Chevy with solid lifters. Lumpy, lumpy idle. Turned out that one of the vacuum lines that I didn't use wasn't capped. After that, runs like a charm.

And are you sure your OBD2 port is hooked up correctly? I don't know, since I haven't gotten mine yet. Recyclers allegedly have it for me, but it has never shown up.

 

You need more that just an OBD reader, you need to see the sensors as well.
If you have a laptop or PDA, then get either the BR-3 or Auterra so you can see what's really going on.

 

Did you make sure your igniter box thingy is grounded?

It will sometimes take a complete warm-up and cool-down cycle before a code will be thrown. If you disconnect the battery cable it will take even longer to throw a code. Did you do the wiring harness? Are you sure the ECU is seeing power with the ignition off? If not, it may never throw a code.

 

Im pretty sure I found the problem. Hooked up the OBD II and took a freeze frame one of the reading was.

Air intake temperature:-40C

Wtf it thinks its minus 40 outside? then I realise I have no IAT sensor to speak of. I gotta track one down and ill update once I have

 

Yep, that's exactly what your issue is.
The IAT sensor should be on the MAF though so maybe it's wired wrong.

 

Whaat? The IAT should be on the AFM?
Do you mean inside?

I found the really weird looking sensor that just looks like a grey plug thats near the afm but not on it

 

Are you using the 5VZFE MAF or the 3VZE AFM?

 

the early style 96-98? 5vzfe MAF

 

wtf is this?! the grey plug I was talking about [IMG][/IMG]

Sorry for the huge pic

 

dont know what that is but the MAF should have a Built in IAT

 

Can you see or clean the built in IAT?

 

I have a '96 3.4 sitting in my garage right now. Going over wiring diagrams and trying to figure out what my next step is.

My MAF loom has the mysterious gray plug taped to it as well. My wiring diagram seems to call it an "idle air control valve"... at least tracing the wire colors on the diagram.

I of course could be way off. Regardless though, I'd make sure your is plugged in and getting it's signal to the ECM.

Wiring diagrams and just about everything else you'll ever need:
https://techinfo.toyota.com/techInfo....toyota.com%2F

$10 for 24 hour access... but you can download and save during that time as much as you want for future reference.

 

I know it isnt the idea air control valve but you say your loom has the gray plug too?? Then I guess its supposed to be there...

Right now im just trying to figure out why my truck thinks its -40C outside

 

You in Alaska hehe , like the previous post said I think also .......if its not hooked up no telling what the ECM is liable to think it is and then again if the ECM is getting a bad signal (polarity problem maybe) then who knows again , I guess go back to the FSM for that motor and trouble shoot Air Temp sensor and see if you get a idea where to look.

 

I'd quote that pic but that is huge.

That is your noise filter, should have been plugged in close to the MAF.

-40 is the default for an open circut, have you checked it electrically?

What are the part numbers off your ECU and wiring harness?

 

the tag from the harness has been ripped off and the ecu is off a 97 4runner for sure

also the wiring harness was done by ORS

SO youre saying that the gray plug is supposed to be there? YAY! Now I have no idea where to look

 

The only lead I have is that its throwing 2 codes

Air Intake Temp Sensor
MAF sensor

 

Could you post a front on pic of that plug so I can see the pins?

 

there are two flat pins about 1mm wide and about 5mm apart