1986 1st Supra Running Poorly

dlfred · 03-14-2010, 06:52 PM

Thanks BTWilson I was hoping someone would tell me where that went. Would there be any reason someone selling the car would disconnect it? It could be he couldn't see where it plugged up once he put most of that area together.

Can anyone tell me what he may have done in order for it to run without the knock sensor hooked up? Would this explain the low power as well?

And to Green7mgte, Thanks for the welcome.

dlfred · 03-15-2010, 12:15 AM

Found a brass nipple with a red o-ring on the side of the block below the intake manifold. Because of the current routing of the wire it looks like I will have to remove the manifold in order to reach the sensor. Any hints or tips on this. It might be a good idea for me to recheck this repair anyway. What do you all think, what would you do?

Thanks

MA70-3.0GT · 03-15-2010, 01:06 AM

Thats the ks with the red seal. It was probably forgotten when the mani was refitted, i'd pull the thing and reconnect (drain the coolant as it runs thru the mani, also fit new mani gasket for the same reason).

Oh by the way, the cx is a eurosport (ec)! It just soldiers on, all ive done is oil, tyres, cables etc.
Oh and one time the temp gauge was running in the red for 2 weeks or so, i thought it was the gauge regulator which is a common thing, except when i opened the rad to change antifreeze it was dry! (never found the cause, no leaks) So yeah they are tough motors with a capital T!

dlfred · 03-15-2010, 01:54 AM

Okay, well I guess I was looking for a good excuse to a redo, there are some things left hanging. Should I do anything with the injectors while I am there? The car sat several years but it ran. Any other stuff I should take care of let me know, for sure i will take care of the exhaust manifold gasket. I really liked Honda's Turbo CX's. My family owned a Honda dealership in the 1980's and early 90's.

dlfred · 03-15-2010, 09:55 PM

Is there a section of the online manual that covers removing the intake manifold? Knowing what is necessary to remove in order to do the job. I have looked for it but do not see it. Do I separate the manifold assembly or remove it as one piece? Does the alternator need to come off ? You get the idea, I just am used to motorcycle factory shop manuals. Thanks

cre · 03-16-2010, 01:23 AM

Hey, got your PM... sorry, been exhausted and busy...

Have you checked for diagnostic error codes?

An intake leak may be causing the high idle, but I'd also check to see if the TPS is properly aligned and that the throttle plate is closing ALL THE WAY when the throttle is released. The throttle bypass screw should also be tightened all the way... it's not used, but for some reason everyone's gotta screw with it (pardon the pun

).

If the car is sluggish until around 4000RPM you should inspect the ACIS system, but it should be kicking in well before 4800RPM unless the TPS is WAY off. The ACIS system modulates the intake's air flow using a butterfly in the middle of the surge tank. If you look down between the forks of the Y pipe you'll see a metal can style diaphragm that's connected to a rod entering the surge tank... this should move when you rev the engine high.

What you need to remove to pull the intake's going to depend on just how much you're planning on pulling... the only trick bit is the coolant hoses which route through the throttle body and through the idle speed control valve and back under the lower intake plenum. Most of the bolt locations and torque specs are in the TSRM under the "Engine Mechanical" section.

dlfred · 03-16-2010, 02:21 AM

No worries CRE, thanks for the additional input. It is great all the solid info that has been given. The code was a 52 and the KS is unplugged and incorrectly routed. In order to connect it and to check all these other things given I am going to disassemble down to the valve cover. I think that the ex. mani is leaking and a possible vaccum leak. I am not sure yet which screw you are talking about but I am sure the previous mech messed with it trying to compensate for the unplugged KS. Did you see the picture with the distributor bolt? Does that look to far off center for the norm? Hopefully I can get busy tommorrow. Still open to suggestions as to where to but OEM parts such as the 45 Intake boot and intake mani gaskets, etc.
Thanks All
When in Doubt...Gas it!

03-15-2010, 01:06 AM	#3
MA70-3.0GT 12psi boost Join Date: Oct 2009 Location: Crewe, England Posts: 356	Thats the ks with the red seal. It was probably forgotten when the mani was refitted, i'd pull the thing and reconnect (drain the coolant as it runs thru the mani, also fit new mani gasket for the same reason). Oh by the way, the cx is a eurosport (ec)! It just soldiers on, all ive done is oil, tyres, cables etc. Oh and one time the temp gauge was running in the red for 2 weeks or so, i thought it was the gauge regulator which is a common thing, except when i opened the rad to change antifreeze it was dry! (never found the cause, no leaks) So yeah they are tough motors with a capital T! __________________ '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!!!

03-15-2010, 01:54 AM	#4
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	Okay, well I guess I was looking for a good excuse to a redo, there are some things left hanging. Should I do anything with the injectors while I am there? The car sat several years but it ran. Any other stuff I should take care of let me know, for sure i will take care of the exhaust manifold gasket. I really liked Honda's Turbo CX's. My family owned a Honda dealership in the 1980's and early 90's. Last edited by dlfred; 03-15-2010 at 01:56 AM. Reason: Punctuation

03-16-2010, 01:23 AM	#6
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Hey, got your PM... sorry, been exhausted and busy... Have you checked for diagnostic error codes? An intake leak may be causing the high idle, but I'd also check to see if the TPS is properly aligned and that the throttle plate is closing ALL THE WAY when the throttle is released. The throttle bypass screw should also be tightened all the way... it's not used, but for some reason everyone's gotta screw with it (pardon the pun ). If the car is sluggish until around 4000RPM you should inspect the ACIS system, but it should be kicking in well before 4800RPM unless the TPS is WAY off. The ACIS system modulates the intake's air flow using a butterfly in the middle of the surge tank. If you look down between the forks of the Y pipe you'll see a metal can style diaphragm that's connected to a rod entering the surge tank... this should move when you rev the engine high. What you need to remove to pull the intake's going to depend on just how much you're planning on pulling... the only trick bit is the coolant hoses which route through the throttle body and through the idle speed control valve and back under the lower intake plenum. Most of the bolt locations and torque specs are in the TSRM under the "Engine Mechanical" section. __________________ 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 --->

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03-14-2010, 06:52 PM	#1
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	Thanks BTWilson I was hoping someone would tell me where that went. Would there be any reason someone selling the car would disconnect it? It could be he couldn't see where it plugged up once he put most of that area together. Can anyone tell me what he may have done in order for it to run without the knock sensor hooked up? Would this explain the low power as well? And to Green7mgte, Thanks for the welcome.

03-15-2010, 12:15 AM	#2
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	Found a brass nipple with a red o-ring on the side of the block below the intake manifold. Because of the current routing of the wire it looks like I will have to remove the manifold in order to reach the sensor. Any hints or tips on this. It might be a good idea for me to recheck this repair anyway. What do you all think, what would you do? Thanks

03-15-2010, 09:55 PM	#5
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	Is there a section of the online manual that covers removing the intake manifold? Knowing what is necessary to remove in order to do the job. I have looked for it but do not see it. Do I separate the manifold assembly or remove it as one piece? Does the alternator need to come off ? You get the idea, I just am used to motorcycle factory shop manuals. Thanks

03-16-2010, 02:21 AM	#7
dlfred 3" Exhaust Join Date: Mar 2010 Location: Georgia Posts: 66	No worries CRE, thanks for the additional input. It is great all the solid info that has been given. The code was a 52 and the KS is unplugged and incorrectly routed. In order to connect it and to check all these other things given I am going to disassemble down to the valve cover. I think that the ex. mani is leaking and a possible vaccum leak. I am not sure yet which screw you are talking about but I am sure the previous mech messed with it trying to compensate for the unplugged KS. Did you see the picture with the distributor bolt? Does that look to far off center for the norm? Hopefully I can get busy tommorrow. Still open to suggestions as to where to but OEM parts such as the 45 Intake boot and intake mani gaskets, etc. Thanks All When in Doubt...Gas it!