1984 Toyota 4x4 Pickup Dilemma!!! 7MGTE Conversion Shout out to Supra Techs!!!
Hi, I appreciate all of you. You have taught an 42 years on the job mechanic a few things. My problem is different than everyone else here because I'm not looking for more horsepower, just to fix someone else's transplant. This 1987 7mgte is actually in this pickup that is itself special. Briefly, this truck is an '84 Toyota 4x4, owned by the same man that bought it new in '84. He actually picked it up from the dock in California when it was delivered from Japan. He took it straight to a fab shop, had the frame extended 3+ feet, and made into a king cab. Added a pop up camper with a walk thru. Drove in for the next 20 years, had the camper removed then the back of the cab resealed. I'm looking for a piggyback setup that will tie into the stock ecm and allow me to read what's doing what and make basic fuel/air adjustment.
I guess about 8 years ago the 22R grew tired and he asked this mechanic if he could add more power. I should note that the owner knows nothing about cars. Well this other mechanic jumped right on installing the 7mgte. He got it up and running, but the owner said that he had problems with the controls that were installed in the dash, and he didn't know how to use them and everything kept going out of adjustment and it wouldn't run right. So he took it back to the mechanic and told him he didn't want the controls, just everything where he could just drive it. Well, it was there a year when the mechanic called him and told him he had to come get his truck, that he lost his shop. So he towed it home and it sat in his garage for another 4 years, with a full tank of premium fuel. He found me a few months back and it was towed here.
What I found was the 7mgte under the hood, disconnected plugs and vacuum lines. an ecm on the floorboards unplugged, more wires. Dash apart, stereo on the seat. The numbers on the ecm decoded to a 1987 Supra, manual. I installed a battery, drained/cleaned tank, the strainer on the pump had rotted away. Replaced the fuel pump, strainer, lines, filter. The hoses were all hard. Plugged in the ecm, changed oil, fresh fuel. Sealed off the open vacuum lines. Couldn't get power to the pump, ran a new wire off the circuit opening relay. It actually fired up and ran, but rich. There was no CEL, no wires run off the ecm. The dashboard wasn't stock because it has the tach and green light that says turbo. Owner said that it had been replaced with the engine. I figure that the dash is outta a 1987 Toyota pickup with the 22RTE because it's the only pickup made with a turbo.
He got some temp tags so I drove it up to emission testing place. It was hard starting all the time but we needed tags. They opened the hood and didn't test when they realized the swap. I had to get an inspection but the state. So.... took it home, paid my tow guy to tow it there. He noticed it was running rich, too and told me to fix that and to ad a charcoal canister. Brought it home. Found the ESRM online manual and started checking stuff out. The way the engine sits in here, there's no way to see the egr and I could hear an exhaust leak in that area. Pulled the manifold and found 1, no line to the cold start injector, it's port in the fuel rail plugged. Also, something he didn't do right during the install. The pipe that bolts to the intake from EGR was missing one of the 2 bolts and the gasket. The remaining bolt was loose. Black carbon coating all of it.
So replaced manifold, new gasket, found a cold start injector feed line and banjo bolts. Later found later that the seal and bypass valve were missing from the ISC valve. I chased down the lead (w) that powers the Check engine light, and the other one is suppose to connect the the gauges fuse. There is not a fuse to the gauges, found it was the 7.5amp fuse for the ecm, though connecting a 12v light in line and it lit. But when I did the jumper wire for diagnostic and turn on the ignition, it didn't flash a code.
Oh, I found that the oil I had replaced was gas soaked. found leaking injectors, found what I thought were direct replacement injectors were not - they were high impedance. So I deleted the resistor, replaced the original connectors with the ones included with the set. Solder and shrink wrapped everything. Found a used ISC valve plus seal and bypass valve. Parts are impossible to find, and nothing new. Compression checks out good. Didn't want to flood the holes so I tested the compression with only about 3 complete revolutions each and got straight 120, figuring limited revolution plus being at 5300' above sea level made up the difference.
It started and ran good for one day. Even with close to the best Snap On diagnostics, Modis Edge 18.4, I can't read the computer. I've done all this plus 1,000 other things. Oh, and the 1 other thing I found was this is missing the high altitude compensator, and the TSRM On-line is from a 1990. I have memorized the every wire and color code, component and ecm pinout test volts and ohms. And after I installed the seal and bypass valve on the IAC, tried starting and nothing - the fuel pump relay had quit, I bypassed it.
I never figure out what he had for engine management. By the open lines off the turbo it appears it had a boost gauge. And this was done like 5-7 years ago.