Help! Supra doesn't run right
- Thread starter Abe's 1987
- Start date
Check Craigs for multimeters, too. I got an old Fluke for $40 or something. 10 years later it's still in my toolbox. Paying full retail for a good name-brand multimeter can be hard to swallow for the average DIY'er. Craigslist is a great place to check to get good stuff at a steep discount.
Harbor freight is great for some of that stuff, too. I've gone through 3 timing lights in my life. 1 was a name brand and lasted 1 year. The replacement lasted another year or so. I bought a harbor freight out of desperation as I needed something immediately and it's lasted me ~8 years and still going strong. Sometimes the harbor freight stuff is just fine.
Harbor freight is great for some of that stuff, too. I've gone through 3 timing lights in my life. 1 was a name brand and lasted 1 year. The replacement lasted another year or so. I bought a harbor freight out of desperation as I needed something immediately and it's lasted me ~8 years and still going strong. Sometimes the harbor freight stuff is just fine.
Question, is there a third party company that sells new afm other then toyota or the toyota afm are the only ones?
Sweet but has anyone here used them, are they good?
Tested all grounds to ecu and to all sensors, all comes up good. Block, head, turbo, intake manifold, tranny, and radiator are all grounded.
Ecu should arrive to my place by Friday. Will install it and see if it makes a difference.
Tested all grounds to ecu and to all sensors, all comes up good. Block, head, turbo, intake manifold, tranny, and radiator are all grounded.
Ecu should arrive to my place by Friday. Will install it and see if it makes a difference.
So having a old camaro z28, in the world of the camaro nuts, the camaro community cuts a door in the trunk in the area of the fuel pump as a easier access to the fuel pump instead of dropping the tank. Ive been contemplating if i should do this with my supra. It would make easy access to the fuel pump if I'd ever need to get to it. What do you guys think about this?
Ive done it before but was thinking of easier ways of working on the it. After all we are getting older day by day, need to take care of ourselves.
Got it. Will test it as soon as I get the meter and let you guys know the data I get. Will most likely get the meter tomorrow.
Also wanted to let you guys know I really do appreciate everyone's help and patience. I'm learning as I'm going along getting the supra running. As a supra community I can say once the car is running it is not just me who got it running but all of us.
Agreed. This site is literally why I got into the MK3 and why at 20 years old with almost no mechanic experience beyond basic driveway oil changes I didn't hesitate to tear into the transmission and engine immediately after buying a mk3. If you're willing to put in the time to research on here and ask thoughtful questions you can do anything with these cars. The community, although thinning out, is awesome.
That kind of thing is why I'm not a "Camaro Guy", haha. No, don't cut a hole to make it marginally easier. Do it right.
Dropping the tank isn't fun, but it's not terrible - especially with a buddy to help hold things in place. Plus, you can clean it up and hit it with a fresh coat of paint or something before it goes back up.
Ok new updates. So I bought the meter today. Hooked it up to ks and e2 backprobed to the ecu. At idle of 1600 rpms it is reading at 0.08 kHz, when gas peddle is fully engaged fast it tops out at 2100 rpms and reads at 0.37 kHz, when throttle is slowly pressed in to wot it tops out at 3800 rpms and reads at 0.30 kHz. After running I smelt a burning smell from the engine or maybe exhaust can't tell as the car sits in the garage reversed in with garage door opened.
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Can the high idle be caused by the afm or ecu or is my tps still not adjusted right? I know I followed the TSRM when adjusting the tps and did exactly as written. The idle adjusting screw on the top of the tb is screwed all the way in yet it still idles at about 1500 rpms.
Good, AFM appears to be working. I would check fuel next. Checking the fuel pressure on this car is not easy, but you may need to do it. You need an adapter for the cold start injector. First, is the AFPR vacuum line hooked up as shown here.
http://www.cygnusx1.net/Supra/TechTips/vacuum_hose.aspx
It is designed to idle pretty fast when cold. But you can check that the IACV is working by shutting the engine off and listen for the IACV to be stepped fully open (it will click for a few seconds after shutoff).
High idle can come from two places. Either the throttle valve is not closing fully, or the IACV is frozen open or not being commanded by ECU. You can eyeball the throttle valve is closing. The IACV you can unbolt and disassemble/clean it. But if the engine is cold the idles speed will be high, so I wouldn't worry about this for now, its not your main problem. That adjusting screw is (was) factory set and never needed to be touched ever. Too late now though.
Note, a pirate air leak will not cause the speed to be high, because its unmetered air and no fuel will be added to match the extra air.
http://www.cygnusx1.net/Supra/TechTips/vacuum_hose.aspx
It is designed to idle pretty fast when cold. But you can check that the IACV is working by shutting the engine off and listen for the IACV to be stepped fully open (it will click for a few seconds after shutoff).
High idle can come from two places. Either the throttle valve is not closing fully, or the IACV is frozen open or not being commanded by ECU. You can eyeball the throttle valve is closing. The IACV you can unbolt and disassemble/clean it. But if the engine is cold the idles speed will be high, so I wouldn't worry about this for now, its not your main problem. That adjusting screw is (was) factory set and never needed to be touched ever. Too late now though.
Note, a pirate air leak will not cause the speed to be high, because its unmetered air and no fuel will be added to match the extra air.
Ok good on the afm. I will swap the ecu first as it already bought and on its way and see what happens. Shipping got delayed but will be here soon enough. I think I have to readjust the tps as I read a more in-depth write up compared to tsrm and think I might be slightly off. Where can I get a fuel pressure gauge, not wanting to spend $100 as I'm seeing most places.
You need this or equivalent to measure fuel pressure. It replaces the banjo at the CSI. https://actron.com/content/banjo-bolt-m1215
Should be 36 psi with the vac line off and plugged.
Easy test for fuel restriction is a snap throttle test. YOu can find videos on how to do it, but here is a summary
First, if the vehicle has a vacuum-controlled pressure regulator (constant volume system), disconnect the vacuum source at the regulator. This keeps the regulator from adjusting the fuel pressure during the test. Next, snap the throttle wide open (WOT) and watch the pressure. It should not drop more than 1.5 psi. If the pressure does drop more than 1.5 psi, there's a fuel delivery problem. No need to do that messy fuel volume test or the test drive.
Should be 36 psi with the vac line off and plugged.
Easy test for fuel restriction is a snap throttle test. YOu can find videos on how to do it, but here is a summary
First, if the vehicle has a vacuum-controlled pressure regulator (constant volume system), disconnect the vacuum source at the regulator. This keeps the regulator from adjusting the fuel pressure during the test. Next, snap the throttle wide open (WOT) and watch the pressure. It should not drop more than 1.5 psi. If the pressure does drop more than 1.5 psi, there's a fuel delivery problem. No need to do that messy fuel volume test or the test drive.
Just ordered the banjo now I need to find a fuel pressure gauge to hook up to that. Does autozone loan them out , cant remember? Rather buy one if the price is right.