Smog help!!!!!

87-POSupra · 12-22-2010, 04:36 AM

i have an 87 supra. i put a 91 motor in and a new catalytic converter. its a non turbo automatic with no mods. it passes perfectly at idle but off idle it fails, not by much but it does. my first thought is to change the ECU considering that the intake manifolds are different which could cause a different air fuel mixture. what are your thoughts????? another tid bit of info is that the car is originally from washington. not sure if it makes a difference but any info you could give is much appriciated. thank you.

btwilson86 · 12-22-2010, 04:43 AM

Do you have the emission printout? I'd be curious to see how it failed and by how much. Off the top of my head, high NO numbers could be a faulty EGR system and therefore not necessarily be catalytic converter related

cre · 12-22-2010, 04:56 AM

If you've got a different manifold on one of the engine's then it's from a difference model Toyota. Swap over all of the different components from your old engine.

BT, you may be right, if it's a Cressida 7M the EGR system probably isn't even there.

How is it failing? Which levels are too high? NOx?

Sonyps307 · 12-22-2010, 10:09 PM

Yea if the intakes r different then it's a Cressida motor the intakes on the supra nonturbo always been the same From 86-1/2 to 92

12-22-2010, 04:36 AM	#1
87-POSupra Stock Join Date: Jan 2008 Location: washington Posts: 16	Smog help!!!!! i have an 87 supra. i put a 91 motor in and a new catalytic converter. its a non turbo automatic with no mods. it passes perfectly at idle but off idle it fails, not by much but it does. my first thought is to change the ECU considering that the intake manifolds are different which could cause a different air fuel mixture. what are your thoughts????? another tid bit of info is that the car is originally from washington. not sure if it makes a difference but any info you could give is much appriciated. thank you.

12-22-2010, 04:43 AM	#2
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	Do you have the emission printout? I'd be curious to see how it failed and by how much. Off the top of my head, high NO numbers could be a faulty EGR system and therefore not necessarily be catalytic converter related __________________ 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

12-22-2010, 04:56 AM	#3
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	If you've got a different manifold on one of the engine's then it's from a difference model Toyota. Swap over all of the different components from your old engine. BT, you may be right, if it's a Cressida 7M the EGR system probably isn't even there. How is it failing? Which levels are too high? NOx? __________________ 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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12-22-2010, 10:09 PM	#4
Sonyps307 Lexus & 550's Join Date: May 2010 Location: Baltimore Posts: 526	Yea if the intakes r different then it's a Cressida motor the intakes on the supra nonturbo always been the same From 86-1/2 to 92