Just Got A MK3

Codelicious · 02-07-2010, 07:45 AM

Hey everyone, I'm new to the forums abd just purchased a 1986(.5) Supra MKIII. Drove great for the first couple of days and still does except sometimes when I start the car it does this "auto rev" thing where it revs from 1k - 2k repeatedly. Also it doesn't go away when driving the car, I drove it for 3 minutes and everytime I push in the clutch it starts again.

Our initial response was the head gasket but the oil looks fine so we think it could be the vacuum hoses? Today while looking under the hood I noticed one wasn't plugged in and I don't know where it goes..

Any help would be appreciated!

Cyto · 02-07-2010, 08:21 AM

It doesn't have an auto rev thing lol. Sounds like your vacuum system is screwed up. Do you have a pic of this hose that's unhooked?

Codelicious · 02-07-2010, 09:26 AM

Sorry I didn't mean to imply that there was an actual auto rev thing. It is just Reving itself up on it's own.

I dint have any pictures of it but I will take some tomorrow and post them up. Thanks for the quick reply. I'm hoping it's something simple like a vacuum hose leak.

hopesanddreams47 · 02-07-2010, 06:08 PM

I've seen that type of thing multiple times in other cars the surging is almost in every case that i have delt with ended up being vacuum, or a tps. have you put your finger over the hose to see how much vacuum its pulling?

Codelicious · 02-08-2010, 06:01 AM

Here are some pictures. Hope these will help you guys help me! lol

--This one is on the left side of the engine bay (passenger side) and comes out by the Fender, I have no idea what it goes to. The other end isn't connected to anything..

--This is about in the middle of the engine bay and had nothing attached to it so we just put a cap over it for now..

--This is just below the first picture I posted, if I remember correctly the hose on the other side leads to the canister.. we put a cap on it because nothing was connected to it..

Started the car up today and it ran just fine.. it only revs itself up on occasion. Hopefully finding the right spots for these will fix it.

btwilson86 · 02-08-2010, 06:42 AM

Can't quite see what I'm looking for in pic 1.

IIRC, the line in pic 2 goes to the BVSV (two pronged vacuum valve on the thermostat housing, they're common to break so yours may be non-existent at this point). The line in pic 3 that runs off of the MAF Sensor should connect to the other end of the BVSV. If there is no BVSV, you may be able to hook the MAF Sensor directly to that nipple on your intake, but then there would be no regulating when the unburnt vapors from your charcoal canister are allowed in your intake.

Codelicious · 02-10-2010, 03:44 AM

So I'v been having problems with my 1986.5 MKIII reving itself up and we thought it was just a vacuum leak.

Tonight when I got home I ran a diagnostic lke cygnusx1.net says to and it came up with the code 43.

Code 43:

Starter Signal

Diagnosis - No "STA" signal to ECU until engine speed reaches 800rpm with vehicle not moving.

Trouble Area
- Ignition switch circuit
- Ignition switch
- ECU

Anyone ran into this problem? I hardly know anything about cars so I don't even know where to start... maybe my $800 Supra was $800 for a reason.. lol

cre · 02-10-2010, 04:07 AM

Code 43 has nothing to do with your idle issues...

Code 43 can indicate an issue when the engine is cranking (which may explain your difficulties when starting the car) or it could appear simply because the car was push started (aka: pop started or dump started). It's not uncommon to see this code just because the car's been started by dumping the clutch while rolling.

Clean your ISCV. You haven't tried to clean the AFM have you? They break very easily. Air filter clean?

BTW - do NOT just make a new thread to post more info... it makes it hard for others to follow and makes it hard for others to find answers to past problems when searching the board. I'm going to merge this with your other thread.

Codelicious · 02-10-2010, 05:33 AM

Sorry about that, didn't think about it not making it easier to help solve the problem.

Thats good to hear because the car was clutch started the other day..

Is the part # for the ISCV 22270-43010.. if so I know where it is and can take it off. I looked at one of the links you posted about removing it. We listened for it to click but didn't hear anything. I don't know if it is good there is no click or bad.. like I said I am clueless about cars right now, this is the first car I have had to work on..

Also what is a AFM?

cre · 02-10-2010, 07:07 AM

Yes, that's the part number for the ISCV (that's Idle Speed Control Valve). Here's the information on testing it: http://www.cygnusx1.net/Supra/Librar...ction=FI&P=106

AFM = a Toyota specific acronym for Air Flow Meter (a certain class of air measuring devices... no not all air measurement devices are an AFM)... You'll VERY commonly see people refer to them as MAF, although that is not accurate.. a MAF (Mass Air Flow Meter) is a term that's specific to another class of device, such as the GM "hotwire" MAF. It's not a huge deal, but it bugs me when a newbie posts back that they can't find the MAF in the repair manual... or better yet, because they bought an actual MAF and can't figure out who to hack the wiring.

There are two different types of air flow meter used in the 7M equipped MKIII... these are:
Karman Vortex (KVAFM) used in the 7M-GTE (NEVER try to clean one with any cleaning solution or solvents!!! These are optical devices and you'll just destroy it.)
Vane (VAFM) used in the 7M-GE. The Vane is a more durable device, but it doesn't age as gracefully due to the use of moving parts and it imposes a certain degree of restriction on the airflow.

02-07-2010, 07:45 AM	#1
Codelicious Stock Join Date: Feb 2010 Location: Oregon Posts: 15	Just Got A MK3 Hey everyone, I'm new to the forums abd just purchased a 1986(.5) Supra MKIII. Drove great for the first couple of days and still does except sometimes when I start the car it does this "auto rev" thing where it revs from 1k - 2k repeatedly. Also it doesn't go away when driving the car, I drove it for 3 minutes and everytime I push in the clutch it starts again. Our initial response was the head gasket but the oil looks fine so we think it could be the vacuum hoses? Today while looking under the hood I noticed one wasn't plugged in and I don't know where it goes.. Any help would be appreciated!

02-07-2010, 08:21 AM	#2
Cyto 3" Exhaust Join Date: Jul 2009 Location: USA Posts: 103	It doesn't have an auto rev thing lol. Sounds like your vacuum system is screwed up. Do you have a pic of this hose that's unhooked? __________________ Proud owner of a 1988 Toyota Supra Turbo, 105k Miles, and great condition. I might have to sell it to help pay for school so here's the link. http://www.toyota-supra.info/forums/...html#post72357

02-08-2010, 06:42 AM	#6
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	Can't quite see what I'm looking for in pic 1. IIRC, the line in pic 2 goes to the BVSV (two pronged vacuum valve on the thermostat housing, they're common to break so yours may be non-existent at this point). The line in pic 3 that runs off of the MAF Sensor should connect to the other end of the BVSV. If there is no BVSV, you may be able to hook the MAF Sensor directly to that nipple on your intake, but then there would be no regulating when the unburnt vapors from your charcoal canister are allowed in your intake. __________________ 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

02-10-2010, 03:44 AM	#7
Codelicious Stock Join Date: Feb 2010 Location: Oregon Posts: 15	I did a diagnostic test.. So I'v been having problems with my 1986.5 MKIII reving itself up and we thought it was just a vacuum leak. Tonight when I got home I ran a diagnostic lke cygnusx1.net says to and it came up with the code 43. Code 43: Starter Signal Diagnosis - No "STA" signal to ECU until engine speed reaches 800rpm with vehicle not moving. Trouble Area - Ignition switch circuit - Ignition switch - ECU Anyone ran into this problem? I hardly know anything about cars so I don't even know where to start... maybe my $800 Supra was $800 for a reason.. lol

02-10-2010, 04:07 AM	#8
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Code 43 has nothing to do with your idle issues... Code 43 can indicate an issue when the engine is cranking (which may explain your difficulties when starting the car) or it could appear simply because the car was push started (aka: pop started or dump started). It's not uncommon to see this code just because the car's been started by dumping the clutch while rolling. Clean your ISCV. You haven't tried to clean the AFM have you? They break very easily. Air filter clean? BTW - do NOT just make a new thread to post more info... it makes it hard for others to follow and makes it hard for others to find answers to past problems when searching the board. I'm going to merge this with your other thread. __________________ 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 ---> Last edited by cre; 02-10-2010 at 04:09 AM.

02-07-2010, 09:26 AM	#3
Codelicious Stock Join Date: Feb 2010 Location: Oregon Posts: 15	Sorry I didn't mean to imply that there was an actual auto rev thing. It is just Reving itself up on it's own. I dint have any pictures of it but I will take some tomorrow and post them up. Thanks for the quick reply. I'm hoping it's something simple like a vacuum hose leak.

02-07-2010, 06:08 PM	#4
hopesanddreams47 Stock Join Date: Feb 2010 Location: sacramento, ca Posts: 2	I've seen that type of thing multiple times in other cars the surging is almost in every case that i have delt with ended up being vacuum, or a tps. have you put your finger over the hose to see how much vacuum its pulling?

02-08-2010, 06:01 AM	#5
Codelicious Stock Join Date: Feb 2010 Location: Oregon Posts: 15	Here are some pictures. Hope these will help you guys help me! lol --This one is on the left side of the engine bay (passenger side) and comes out by the Fender, I have no idea what it goes to. The other end isn't connected to anything.. --This is about in the middle of the engine bay and had nothing attached to it so we just put a cap over it for now.. --This is just below the first picture I posted, if I remember correctly the hose on the other side leads to the canister.. we put a cap on it because nothing was connected to it.. Started the car up today and it ran just fine.. it only revs itself up on occasion. Hopefully finding the right spots for these will fix it.

02-10-2010, 05:33 AM	#9
Codelicious Stock Join Date: Feb 2010 Location: Oregon Posts: 15	Sorry about that, didn't think about it not making it easier to help solve the problem. Thats good to hear because the car was clutch started the other day.. Is the part # for the ISCV 22270-43010.. if so I know where it is and can take it off. I looked at one of the links you posted about removing it. We listened for it to click but didn't hear anything. I don't know if it is good there is no click or bad.. like I said I am clueless about cars right now, this is the first car I have had to work on.. Also what is a AFM?

02-10-2010, 07:07 AM	#10
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Yes, that's the part number for the ISCV (that's Idle Speed Control Valve). Here's the information on testing it: http://www.cygnusx1.net/Supra/Librar...ction=FI&P=106 AFM = a Toyota specific acronym for Air Flow Meter (a certain class of air measuring devices... no not all air measurement devices are an AFM)... You'll VERY commonly see people refer to them as MAF, although that is not accurate.. a MAF (Mass Air Flow Meter) is a term that's specific to another class of device, such as the GM "hotwire" MAF. It's not a huge deal, but it bugs me when a newbie posts back that they can't find the MAF in the repair manual... or better yet, because they bought an actual MAF and can't figure out who to hack the wiring. There are two different types of air flow meter used in the 7M equipped MKIII... these are: Karman Vortex (KVAFM) used in the 7M-GTE (NEVER try to clean one with any cleaning solution or solvents!!! These are optical devices and you'll just destroy it.) Vane (VAFM) used in the 7M-GE. The Vane is a more durable device, but it doesn't age as gracefully due to the use of moving parts and it imposes a certain degree of restriction on the airflow. __________________ 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 --->