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Ali i noticed your temp sensor is on your turbo inlet pipe. wouldn't it get a more accurate reading mounted on the intake manifold itself or is there a benefit for having it before the turbo? there is probably a temp difference between the two points so i am curious. im looking for a place to stick mine
yeah it was a lazy move on my part I didnt have time to get a bung welded and I am not tapping it straight into the intake manifold because I don't want it to heatsoak. The toyota ecu is not as sensitive to the IAT as a standalone would be, but yeah I would put it on the last intercooler pipe before the throttle body, that is where I am moving mine when I get a chance.
Generally the IAT will only make the ecu trim the fuel a little bit, I am not sure if it even trims timing.
Since I have it stuck in my turbo intake pipe I should be seeing hotter values than after the intercooler and not on a hot pipe, so right now it should inject less fuel, but the funny thing is my AFR's are always really rich in the 10's-11's so I wonder on this ecu how much it even matters. When I move it to the other pipe it should read colder and thus give me more fuel... so I hope the AFR's don't move too much and the coils can keep up with that. I am guessing its not going to change how it runs much with the stock ecu, it probably zeroes out the trim above 70-80 degrees anyways. usually they add in fuel when its cold and zeroes out up top.
I remember the old school supraforum members used to never run an IAT and just stick in a resistor that puts it at operating temp. I Think this way you get no trims which is handy if you have a vpc or something like that. some used to leave it hanging in the engine bay, cause at first the engine bay is not hot, but as the engine heats up the engine bay temp rises sort of similarly and this is close enough that the ecu thinks its normal that you went from cold to heatsoak... I think mine is just a neater version of that. IT works well enough the car doesn't skip a beat but yeah I will be moving it to the throttle body area as its more accurate =)
Well the igniter pins were fun, also they are different colors than the posts I have seen so I went based on there location 1-5 I think it was correct because the +b was actually a black/white wire with a bright green gromit.
As soon as I saw a pale green wire I knew something was off.
the locations on that diagram for the stock coil is not accurate I don't think.
the b+ I thought was always black/orange on toyota/lexus. it will be the 1 wire that is thicker than the others.
maybe post a picture.
this is what the one on a 95 supra looks like. the wire colors are different but it does mention the pin numbers
looks like the black white on this one is the tach...
I updated post 1 with the above info and also the wiring for the o2 sensor. thanks eblick99 I borrowed it when you it please confirm for me its right, thanks!
this is what it looks like on a stock 4 wire car (95 USDM Supra TT first o2 sensor of 3 shown)
That's how I wired up my 4-wire O2. I've got all my ECU wiring and bay wiring done except the IAT and MAP sensors. The wires are run and all is ready, I am just waiting on an intake pipe to use so I can mount the IAT and then wire it up. I ran all the wires through the stock loom, it looks totally stock in the bay, I can't wait to get it all done and fire it up! Valve covers have been sand blasted, drilled and tapped 1/2"npt and 5/8" barbs installed, painting them now.
Sounds like you are making alot of progress which is good. you ran it all in the stock loom.. that is going above and beyond I still have some wires separate but it will look good that way, way to go, it will look cleaner and protect the wires better. can't wait to see it hopefully you will post up some pics when you are done.
Also for those using the USDM ecu, I forgot to mention you guys need to use 2 o2 sensors on the downpipe.
here is a pic of my FFIM, the two bungs you see in pic on the side are mounts for the tb cable bracket. two more ports on opposite side (not visible) are for vacc hoses. i might put the IAT on the ffim, is this a bad idea? you mentioned heat soak so maybe ill try and put it on IC pipes.
also i noticed i have two cans under my lower intake runners, circles (2) and (3), and the upper has a connector maybe (1). not sure which is which, i need a mirror to see under there better. if i can remove either thatd be nice, although im not sure i can reach them
also what do i do with the two heater hoses that used to go up over the motor?
ill do the wiring for the 12v fuel mod and the 4 wire O2 sensor on thursday, if i have the ffim installed by then i will fire her up as well and see how she does. hopefully it runs well and not a big turd.
well the stock IAT is on the intake manifold, so its not a bad idea just not where I wanted to put it.
I rather have it on the intake pipe just so its not permanent its easier for me to change the intake pipe then the intake manifold if I need to access it or whatever.
FFIM looks interesting, in to see the results.
your picture is sort of too small I can't make out what that is but might be the vac canister I was talking about a few posts back, its like a brown color and has a brown vsv on the top of it. its held on by 2 nuts at the top (stick camera phone down there and take a picture to see). I have done it enough times to reach it by feel but you can see it from different angles. Just make sure you are not messing with the starter which is also canister shaped but much much lower on the engine (all metal looking).
also to note if you have trac control you may have some extra stuff in that area, I do not have trac control so can't say what exactly but I have had a car that had it and there was extra metal canister and stuff, do not remove those without looking it up, its not very easy. the vacuum canister I am talking about is brown and plastic and has vacuum lines coming off of it (rubber ones). not metal lines like the trac control would have.
for the last pic, yeah that is what I did I put bolts that were a tight fit and then used hose clamps on top of them (not the factory ones but better ones) to keep it from leaking at all. has held up fine. I actually have a spare drivers side waterneck.. if you follow the hose back to where it comes out of the waterpump on the drivers side, there is a nipple on the waterneck thing where that hose attaches, and if you try you can remove the nipple easily with vice grips just clamp down and keep twisting it and itll work itself right out.. (toyota press fits all of these they are not welded or anything). once you are left with just the hole you can actually tap that hole for 1/8 NPT fitting, and you can plug it or put a spare coolant sensor on there instead of having that hose coming out. IF you wanted in the future you could also put in a 1/8" hose barb and put the hose back. so that is how I would delete the drivers side if you felt like going all the way. You can also just get it welded shut obviously instead of tapping and stuff, but tapping and fittings I can do at home, welding I have to drive down to where the welder is.
for the passenger side to get rid of it, the line comes off a hardline towards the rear of the motor, and so you cannot drill or tap that. really its got to come off the motor to get welded or maybe braze a plug or fitting on. I have not gotten around to either of these as I don't want to drain my perfect toyota red coolant thats in there just for doing that, but next time I drain the coolant both those are getting deleted.
Btw I have had it over a year with the bolts and clamps and not a single drop, but do realize its not the most permanent solution in the world. I will post a picture of the drivers side neck I modified later on. Its in my box o parts that need to make its way on to the car eventually...
Here's how she sits right now, harness is all done except wiring up the IAT and MAP sensors and the O2 sensor. Still waiting on a quick disconnect plug to come in for O2 and the intake pipe to come in for the IAT.
I am still using the vacuum canister and fuel stuff, but removed all EGR stuff. There is a green connector right behind the power steering pump and below the intake runner that I cannot remember what it connected to. I know the black connector for the EGR VSV is on top with the fuel rail, that one can hang loose. Any ideas about the green connector though (it's not showing in that pic, I can take one when I get home though)?
looks like you are getting there. what ffim did you get you may need to relocate the power steering reservoir if its the kind like mine.
green connector sounds like the coolant temp sensor it should be sticking out the side of the head by runner 1. there will also be a grey one close to that which is also a coolant temp sensor. the green one is for the ecu 2 pin, and the grey one is a 1 pin for the cluster. the black one yes that is for the egr it can hang if its not on the motor.
Do you mean the charcoal canister for the fuel tank? I left that and the vsv and lines for it. There is a line from the tank to vsv, line from vsv to intake, and there is also a "Tee" and a check valve with a line going to the throttle body I think. you can see it on the underhood vacuum diagram (or look at the stock intake you just removed and copy) and just run new lines cause normally it goes through the metal hardlines under the stock Y piece which you are removing (which is where the check valve is underneath, its blue/black, you can borrow that one for your new lines).
very interesting heater switch delete you have there. did you just put a valve inline so you can turn it off? I guess in texas you wont need the heat except for a bit of the winter.
also is your harness or motor from a supra, normally the diagnostic port is by the valvecovers on the SC. where it is on the firewall actually seems like a better place to have it.
I didn't do a heater switch delete, that is a hookup to flush the coolant system. I actually bought a new hose to replace that, it leaks on my valve covers and I don't like that... And yeah, I actually have a 95 Supra, I'm here because you guys have all the get-your-hands-dirty knowledge and mindset, and have been super helpful!
On that green plug, that was my first thought too and now that I think about it I know what happened... I got a new one to replace it and then saw how much of a pain in the butt it will be to change out and decided against it. I'll be pulling the head later on when I upgrade the hg anyway, I'll do that crap then.
yeah if it works I would leave it. its just a coolant sensor. I usually break them when I try and remove the clip, although I have gotten a little better each time.
i never found a maroon cannister, there is a black plastic can right under the lower runners with two bolts. i removed it, toyota part 90910-12124 vaccuum cannister valve? if i can get rid of this ide rather not reinstall it everything else is completely done except ic piping. ide post pics but my iphone wont let me.
09-11-14, 10:23 PM
everything else is completely done except ic piping. ide post pics but my iphone wont let me.
