Project LOLTRAC, or ST185 BS - a USDM Alltrac restoration

alltracman78":22diqo69 said:

It's an older style Toyota intake temp sensor. Our cars have the intake temp sensor in the AFM. Looks like for whatever reason they cut the one in the AFM out and used one they installed in the intake tube.
Also, it looks like that AFM connector is a regular one, not a homologation one. Post up a pic of the AFM itself.

The homologation engine is almost 100% identical to the regular 185 engine. Aside from the AFM connector you can take that engine and stick it right in a regular 92/93 185 and the harness will connect right up. You can run either engine with either ECU.
You can even run either AFM with either ECU (I've done it out of curiosity, not for an extended period of time. But it accelerated and ran fine. No codes, no stumbling, nothing.). I'm not suggesting you should, just that it's doable.

The different stuff is due to JDM vs USDM stuff and not homologation vs non homologation.

That "device next to the MAP sensor" is an electronic AC idle up. USDM uses a vacuum one.
The vacuum lines are slightly different for the EVAP and lack of an EGR.

Click to expand...

MAF did not come with the motor, unfortunately, so no pics of that...

So how difficult is it going to be to hook up a JDM motor in a USDM car and have all of the accessories and everything work? Like can I wire in the electronic AC idle up? or am I basically stuck disabling that feature?

If you swap over all your USDM accessories and harness to the JDM shortblock I'd think it'll work just like a USDM motor.

The accessories are all the same. They hook up just fine to the US harness [assuming you have the same revision. If not just the alternator harness is different, and you can use the one from your engine.].
Either ECU will work with the harness and engine. The homologation ECU will need 1 extra wire added and ran to ground or it will throw a code for the intercooler. I don't remember which pin but it's in the body harness connector to the ECU. Also, ideally you want the homologation AFM to go with the ECU. It's larger than the regular one.
The problem is if you use the JDM ECU it doesn't work correctly with the US AC computer. The AC should turn on but the engine won't idle up [not because of the VSV]. Coldiron ? should have a pretty detailed thread about it.

There are a few extra VSVs and things on the JDM engine that you won't need. That AC idle up VSV, the VSV for the charcoal canister and the EGT sensor after the cat.
You can just leave the EGR connector hanging. And take a close look at the vacuum tubing, they're slightly different for the emissions stuff.

That's all I can think of off the top of my head; been a while.

Problems abound! The turbo impeller doesn't turn freely, and when turning it by hand it begins oozing oil mixed with coolant.



So I looked up the ECU part number, and it's not a Celica ECU at all! It's from an MR2 SW20. Would explain some of the wiring harness fuckery.

I'm contacting the seller, going to see about sending it back, as this is way too sketchy for what I paid.

Okay update time.

I found the source of one boost leak. The power steering idle up valve was broken off the pump and left dangling by some past mechanic... where it eventually snapped off the connector to the manifold. So I was able to fix that at least.

I found more issues though.

Firstly, and maybe I just don't understand how this is supposed to work, but...



Any pressure I put into the intake is lost unless I plug this hose up here. This recirculates back into the intake after the MAF but before the turbo. If I plug that hose, I can build pressure with the boost leak tester. I'm not sure what this is supposed to be, but I'm relatively sure it isn't supposed to be dumping boost out of it.


It seems to be connected to the AC idle up valve and then runs back into the mess under the manifold somewhere.


When I pinch this hose I don't hear/feel any hissing, so I presume the boost is escaping from somewhere else.

Any ideas? Or is this 'normal' with the motor not in operation?


This device, whatever it is, is shown to be leaking also via the smoke test. Anyone know what it is or where I'd get a replacement?

I can also hear a hissing sound coming from the EGR valve as I build boost. Is that normal or does it need to be replaced? can it even be replaced? seems the part is discontinued and ebay shows nothing.

Last bit of bad news is the gas tank is leaking somewhere up near the top, and I can't find any info on replacement gaskets I'd need to take it down and look at it.

EvilStig":20cjghlk said:

Any pressure I put into the intake is lost unless I plug this hose up here. This recirculates back into the intake after the MAF but before the turbo. If I plug that hose, I can build pressure with the boost leak tester. I'm not sure what this is supposed to be, but I'm relatively sure it isn't supposed to be dumping boost out of it.

Click to expand...

Sounds like crankcase vent. The pressure is bypassing piston rings and coming out that tube but shouldn't be much flow, especially when running, if it seems like a lot is coming out i would do a compression test if you haven't already. If there's any valve overlap with where the engine rotation ended up there could be pressure going out the exhaust too.

Sorry I lied, the hose closer to the front of engine connecting to valve cover is crankcase vent. The other one goes to idle up as you said and IAC valve under TB and somewhere else too i think. So if the IAC is still open at all then that's where the pressure was going. Im not sure when if ever the IAC is supposed to be 100% closed. The manuals have lots of testing procedures for the EGR valve etc. and probably the IAC, maybe that's related to your idle issue? I may have missed it but i didn't see any details about your idle issue, does it never seem to change it as it warms up?

A Major Milestone Reached! The hard part is done, and she runs and drives!


You'll have to forgive just a couple recycled photos in this post, since I'm just ecstatic with how well this came out and I wanted to show it off. This one's fresh though. Drove her to work this week.


Close-up of the beautiful carbon fiber hood. I really just don't have the heart to paint over it to make it match.


Latest good picture of the engine bay. I think the best description I can come up with for it is "a nightmare difficulty 3D Factorio game." Last weekend I took it out for a drive, and the power steering idle up vacuum switch backed out again. I had to get it towed back to the house, where I safety-wired it back in before driving it to the shop, along with a new A/C compressor, pump, and vacuum switch. My local Saint installed it all for me and had it ready for pickup the same day. I spent the remainder of the week making fine adjustments to the dual-port BoV and EBC. It will ramp to fuel cut at 15PSI quickly if I turn it up above 40% gain. I have performance mode set to 14 PSI with an alarm at 13.5 so I know when I've pegged it. The butt dyno approves. Daily mode I've got at a more conservative 10.5 PSI


Interior is looking and feeling like home. I love how it came out, and I especially love the new pedals. They're helping immensely with my heel-toe training.


Slightly older photo of the interior showing off the nice leather seats from a better angle.


plastic blank plate over where the ashtray used to be holds the turbo timer and EBC interface. The shifter boot panel features a commemorative placard dedicating the car to Behruz Shahrivar, without whom this restomod never would have been.


And that's where we're at now... and I'm enjoying driving it around while saving up the dosh to get it painted, which will be the next step. I found a local guy who runs a shop called Apex Autobody in San Jose, and he's quoted me ~$6k for all the body repair work and a full repaint including original bumper and hood.

further issues abound and I've burned out an o2 sensor and the wideband AFR. Ended up throwing a code again, and that one cylinder is still struggling with compression. I'm calling around for quotes on a full upper/lower rebuild, or to find a replacement motor to swap in.

I also have my sights on a full brake and suspension overhaul with Feal 441+ and whiteline parts, hypergram wheels, R1R tires, and Hawk HPS.... and my trigger finger is getting itchy.

I came across this thread while searching for information on Behruz. I'm honestly stunned that this car is still on the road and would love to see it in its current state one of these days.

Obviously I don't know the entire history of the car, but from what I do know, you gave an abridged version of it. I recall one of the previous owners having blown an engine due to a technician at Steven's Creek Toyota not properly fastening something vital (it's been a long time, can't recall exactly). The owner had to argue back and forth with them a bit before they provided a crate block that they half-assed the installation of, to say the least. That was where Behruz came in, and while I may have handed him a tool or two, held a hose or two, etc., he was truly the brains of the operation and without him the car would never have been able to get off the jackstands it sat on for nearly as long as either of us had known the car's owner at that point.

Seriously, good job on keeping this car running. All the more impressive that you've made it look good while doing it.