1986 1st Supra Running Poorly

MA70-3.0GT · 03-13-2010, 11:57 PM

First off welcome and i hope you find the forum as much use as i have. I cant see the pics as im on mobile atm but if you suspect the intake may be leaking post AFM that would cause high idle and iffy power so thats first on your list. Before you buy parts though check the pas idle up valve connection under the intake pipe, its 1/2" approx rubber hose leading from the intake to a round valve on top of the pas pump then from that to the steel vac pipe that runs across the front of the motor under the water pump. If that and the intake pipe checks out and you still hear a vac leak the tsrm has great diagrams of all vac hose routing, maybe someone on a pc could post a link?
Failing all that the idle control valve could be sticking, although that would usually cause more distinct issues. I'm tired and my phones being funny so am gona post quick an if i think of anythin else il get back.

dlfred · 03-14-2010, 12:30 AM

Thanks for the post that is some stuff I didn't even think of, Thank you. I may have to get some more details I will check it out. Sounds like you are going to be sleeping soon but the Supercross is coming on TV at 7:30 est. I will be in the "Supra Web Search" mode for the next 3.5 hours while watching. So a Honda 500 Custom, those CX motors are tough, cool.

dlfred · 03-14-2010, 12:35 AM

Just to save someone some time I have scored the diagrams mentioned. Awesome stuff that online manual, allot I pulled from the search option.

btwilson86 · 03-14-2010, 04:48 PM

Looks like you may not need a knock sensor, that green one wire connector is your knock sensor wire. IIRC, it should plug in to a fairly large knock sensor a little closer to the front than half way down the block on the intake side of the engine.

dlfred · 03-17-2010, 12:45 AM

Quote:

Originally Posted by MA70-3.0GT

First off welcome and i hope you find the forum as much use as i have. I cant see the pics as im on mobile atm but if you suspect the intake may be leaking post AFM that would cause high idle and iffy power so thats first on your list. Before you buy parts though check the pas idle up valve connection under the intake pipe, its 1/2" approx rubber hose leading from the intake to a round valve on top of the pas pump then from that to the steel vac pipe that runs across the front of the motor under the water pump. .

Removed the throttle body and was able to route the KS wire down between the manifold. Should be able to connect it tomorrow. This thing is nasty up inside the mani. Now I have tough decision of cleaning it all up now or get the car running correctly to be sure there aren't any major deals with the motor, then disassembling it to clean again later.
The steel line that runs across the front of the motor, it sure looks beat up, It looks a little dented and bent. Should that be a problem? Should I assume it's bad and replace it? What do you think?

dlfred · 03-17-2010, 02:01 AM

This is the BVSV, it has nothing connected to it? Does it need this in the loop to run correctly?

cre · 03-17-2010, 03:02 AM

Yeah, run the charcoal canister's purge to the BVSV and from there to the TB. It's a flow control which prevents the charcoal canister fro providing extra fuel when the engine is below a certain temp.

dlfred · 03-17-2010, 03:30 AM

The BSVS has one of the nipples broken off. Is there a fix or just get another?

Nice info link at the bottom of your last post CRE.

Thanks folks

cre · 03-17-2010, 04:45 AM

The BVSV's are very expensive new and I don't know of an aftermarket solution. The best bet is to hit up a salvage yard and grab a couple off any Toyota's of a similar vintage. Most will fit and operate at a similar temp.

Thanks, I really need to update some things and add a couple new wiring diagrams, but you know how it goes... other priorities and all that.

dlfred · 03-19-2010, 12:17 PM

Have everything out of the way and was able to plug in the KS. Now I have to be able to check the vacuum line routing and connections. I guess I can understand the lack of clean up for a flat rate mech, but man it sure was nasty in there. What causes that much intake goo? It looked like mud/grease all though the intake plenum and box. It is now much cleaner.
There is a small 2 hole bracket with vacuum line hook ups, on the drivers side below the intake. Any ideas on what those 2 bolt holes line up too? This thing has been good to work on so far. Thanks

03-13-2010, 11:57 PM	#1
MA70-3.0GT 12psi boost Join Date: Oct 2009 Location: Crewe, England Posts: 356	First off welcome and i hope you find the forum as much use as i have. I cant see the pics as im on mobile atm but if you suspect the intake may be leaking post AFM that would cause high idle and iffy power so thats first on your list. Before you buy parts though check the pas idle up valve connection under the intake pipe, its 1/2" approx rubber hose leading from the intake to a round valve on top of the pas pump then from that to the steel vac pipe that runs across the front of the motor under the water pump. If that and the intake pipe checks out and you still hear a vac leak the tsrm has great diagrams of all vac hose routing, maybe someone on a pc could post a link? Failing all that the idle control valve could be sticking, although that would usually cause more distinct issues. I'm tired and my phones being funny so am gona post quick an if i think of anythin else il get back. __________________ '89 MA70 Supra GT aero 3.0turbo JDM, Rebuilt motor, K&N intake, 3" stainless turbo-back. New turbo and braided line kit... '89 Honda NC27 400, NC23 cams, open pipe, PC36a shock & possibly Showa USD forks... '83 Yamaha 29R XJ750E-II, number 69 off the line, only runner in the country? Original except Koni shocks '95 Honda PC26 CB500R, Winter hack, hateful, trying to sell it I'm not paranoid, they really ARE after me!!!

03-14-2010, 12:35 AM	#3
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	Just to save someone some time I have scored the diagrams mentioned. Awesome stuff that online manual, allot I pulled from the search option. Attached Thumbnails

03-14-2010, 04:48 PM	#4
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	Looks like you may not need a knock sensor, that green one wire connector is your knock sensor wire. IIRC, it should plug in to a fairly large knock sensor a little closer to the front than half way down the block on the intake side of the engine. __________________ 1989 7MGTE R154 Targa Top White Package w/Blue Interior Driftmotion 57trim CT26, Upgraded Intercooler, 2.25" Hard Pipes, 3" Turbo Back Exhaust with Test Pipe, HKS VPC w/GM 3 bar MAP sensor, APEXi S-AFC, Walbro 255lph fuel pump, ProSport EVO Series Boost / Fuel Pressure / AFR gauges, Lotek a Pillar Gauge Pod, HKS Type 0 Turbo Timer, Eibach Lowering Springs, Tokico Illumina II TEMS struts, custom powder coated Motegi Racing TrakLite wheels

03-17-2010, 02:01 AM	#6
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	This is the BVSV, it has nothing connected to it? Does it need this in the loop to run correctly? Attached Thumbnails

03-17-2010, 03:02 AM	#7
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Yeah, run the charcoal canister's purge to the BVSV and from there to the TB. It's a flow control which prevents the charcoal canister fro providing extra fuel when the engine is below a certain temp. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

03-14-2010, 12:30 AM	#2
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	Thanks for the post that is some stuff I didn't even think of, Thank you. I may have to get some more details I will check it out. Sounds like you are going to be sleeping soon but the Supercross is coming on TV at 7:30 est. I will be in the "Supra Web Search" mode for the next 3.5 hours while watching. So a Honda 500 Custom, those CX motors are tough, cool.

03-17-2010, 03:30 AM	#8
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	The BSVS has one of the nipples broken off. Is there a fix or just get another? Nice info link at the bottom of your last post CRE. Thanks folks

03-17-2010, 04:45 AM	#9
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	The BVSV's are very expensive new and I don't know of an aftermarket solution. The best bet is to hit up a salvage yard and grab a couple off any Toyota's of a similar vintage. Most will fit and operate at a similar temp. Thanks, I really need to update some things and add a couple new wiring diagrams, but you know how it goes... other priorities and all that. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

03-19-2010, 12:17 PM	#10
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	Have everything out of the way and was able to plug in the KS. Now I have to be able to check the vacuum line routing and connections. I guess I can understand the lack of clean up for a flat rate mech, but man it sure was nasty in there. What causes that much intake goo? It looked like mud/grease all though the intake plenum and box. It is now much cleaner. There is a small 2 hole bracket with vacuum line hook ups, on the drivers side below the intake. Any ideas on what those 2 bolt holes line up too? This thing has been good to work on so far. Thanks

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