performance result from wrong injectors

cre · 04-09-2013, 12:17 AM

You need to fix the code 52 BEFORE anything else. It changes the way the ECU handle a lot of things in a MAJOR way. Look in the MKIII FAQ section for a thread about code 52 and knock sensor rewire. Often the wiring just needs to be replace with better wiring and a new connector is recommended. The knock sensors are very pricey so try the rewire first.

Make sure the TPS is for the right year. There was a change mid '89 and the interface tabs are clocked 90? different from earlier years. This will hold the throttle plate open, but I think it hold it open to a much greater degree than you're seeing.

bitsoknittles · 04-18-2013, 05:41 AM

Thanks CRE. that will be my next section of the motor to work on. I am presently removing the whole intake (from the throttle body to the block) and using carb cleaner to clean all the sludge/gum from the bad gas that had been sitting in it. I do have a question on the N/A; if air were forced into the intake/throttle body, what would happen to the performance? would it increase the power (using cooler air from the front of the vehicle, not the warmer, under-the-hood air) or just the gas consumption? If it would increase the performance, I have an idea....

cre · 04-18-2013, 06:38 AM

The factory intake is a cold air intake. It's not restrictive either as long as you use a GOOD filter element in it. Removing the passenger side footlights and making sure all of the under covers may increase air pressure when already driving at speed but even with an elaborate duct you're not going to see any massive increases in power. Keep the helmhotlz resonator and don't increase pipe diameter as it reduces air velocity which is more important on a non-turbo. I've written a lot about all of this on here before.... might be in the. FAQ thread about cold air intakes.

bitsoknittles · 05-24-2013, 01:44 PM

Thanks for the previous info on the emissions CRE; I recently did a retest and the NOX passed (barely, 2.23 of 2.5), but the CO and the HC still didn't. HC was at 3.96 of allowable 1.6 and the CO was 117.31 of allowable 15.0. The idle is still a little high, but it seems to be running rich. Any ideas? The timing is at 10@ BTDC, and I have checked and set the TPS, checked the ISC and the air flow sensor settings, etc, according to the factory recommended settings/values. Any help would be appreciated as to where to look/ what to fix/reset/replace. Thanks!

04-09-2013, 12:17 AM	#1
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	You need to fix the code 52 BEFORE anything else. It changes the way the ECU handle a lot of things in a MAJOR way. Look in the MKIII FAQ section for a thread about code 52 and knock sensor rewire. Often the wiring just needs to be replace with better wiring and a new connector is recommended. The knock sensors are very pricey so try the rewire first. Make sure the TPS is for the right year. There was a change mid '89 and the interface tabs are clocked 90? different from earlier years. This will hold the throttle plate open, but I think it hold it open to a much greater degree than you're seeing. __________________ 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 --->

04-18-2013, 06:38 AM	#3
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	The factory intake is a cold air intake. It's not restrictive either as long as you use a GOOD filter element in it. Removing the passenger side footlights and making sure all of the under covers may increase air pressure when already driving at speed but even with an elaborate duct you're not going to see any massive increases in power. Keep the helmhotlz resonator and don't increase pipe diameter as it reduces air velocity which is more important on a non-turbo. I've written a lot about all of this on here before.... might be in the. FAQ thread about cold air intakes. __________________ 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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04-18-2013, 05:41 AM	#2
bitsoknittles Stock Join Date: Mar 2013 Location: Phoenix, Az Posts: 5	Thanks CRE. that will be my next section of the motor to work on. I am presently removing the whole intake (from the throttle body to the block) and using carb cleaner to clean all the sludge/gum from the bad gas that had been sitting in it. I do have a question on the N/A; if air were forced into the intake/throttle body, what would happen to the performance? would it increase the power (using cooler air from the front of the vehicle, not the warmer, under-the-hood air) or just the gas consumption? If it would increase the performance, I have an idea....

05-24-2013, 01:44 PM	#4
bitsoknittles Stock Join Date: Mar 2013 Location: Phoenix, Az Posts: 5	Thanks for the previous info on the emissions CRE; I recently did a retest and the NOX passed (barely, 2.23 of 2.5), but the CO and the HC still didn't. HC was at 3.96 of allowable 1.6 and the CO was 117.31 of allowable 15.0. The idle is still a little high, but it seems to be running rich. Any ideas? The timing is at 10@ BTDC, and I have checked and set the TPS, checked the ISC and the air flow sensor settings, etc, according to the factory recommended settings/values. Any help would be appreciated as to where to look/ what to fix/reset/replace. Thanks!