ecu malfunction?
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ecu malfunction?
92 4runner 3vz-e 4x4 manual transmission
I have been having troubles with high idle on my runner since I've owned it, checked for vac leaks and done all sorts of tune up projects. About a week ago, my ect pwr light switched on on my dash and I found it odd since my truck is manual. I then considered a short in my dash making the light illuminate, but have since found out that it is a check engine light ( I jumped the two test terminals and got a code reading of 21... O2 sensor).
In theory, the idle issues and minor "bucking" in 2nd gear could be a result of a malfunctioning ecu, but could it in fact throw on the wrong light? I'm hesitant to replace the O2 sensor right away in the case that the ecu is bad, I'd hate to screw up the new one. Any ideas or thought? Thanks.
I have been having troubles with high idle on my runner since I've owned it, checked for vac leaks and done all sorts of tune up projects. About a week ago, my ect pwr light switched on on my dash and I found it odd since my truck is manual. I then considered a short in my dash making the light illuminate, but have since found out that it is a check engine light ( I jumped the two test terminals and got a code reading of 21... O2 sensor).
In theory, the idle issues and minor "bucking" in 2nd gear could be a result of a malfunctioning ecu, but could it in fact throw on the wrong light? I'm hesitant to replace the O2 sensor right away in the case that the ecu is bad, I'd hate to screw up the new one. Any ideas or thought? Thanks.
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#4
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Use the FSM to test the ecu. There is a link in my sig
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1990 4runner, 22re, R151, 4.7, 5.29s, E-locker front, Lock-Rite rear, 37" MTRs, 51" rears all around
Trail Reviews http://www.gentryoffroad.com
Toyota Factory Service Manuals http://ncttora.com/fsm/index.html
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1990 4runner, 22re, R151, 4.7, 5.29s, E-locker front, Lock-Rite rear, 37" MTRs, 51" rears all around
Trail Reviews http://www.gentryoffroad.com
Toyota Factory Service Manuals http://ncttora.com/fsm/index.html
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I do not know much about the 3.0. I have heard if it is running really rich it can foul an 02 sensor, but I do not know if it is true or not. When you replace your O2 sensor use a denso. You can buy them for a reasonable price at http://www.sparkplugs.com
Denso OE identical O2 sensor $66.51
Denso OE identical O2 sensor $66.51
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Don't know on a 3.0 Here is a link to the trouble shooting guide in the factory service manual. http://ncttora.com/fsm/1990-1995_4Rn...e/troubles.pdf
On my 22re I have had it from air flow meter and o2 sensor. I have read that the throttle position sensor, coolant temp sensor and cold start system can also cause this but I don't know if it applies to the 3.0
I would try the o2 sensor first. If that doesn't do it go threw this with a volt/ohm meter.
http://ncttora.com/fsm/1990-1995_4Rn...e/troubles.pdf This tests the computer and makes sure the efi components are working correctly.
On my 22re I have had it from air flow meter and o2 sensor. I have read that the throttle position sensor, coolant temp sensor and cold start system can also cause this but I don't know if it applies to the 3.0
I would try the o2 sensor first. If that doesn't do it go threw this with a volt/ohm meter.
http://ncttora.com/fsm/1990-1995_4Rn...e/troubles.pdf This tests the computer and makes sure the efi components are working correctly.
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I intend on testing the ecm soon, but with a VERY pregnant wife, my time is extremely limited. I'm getting the o2 sensor tonight, just hate the idea of fouling it and needing to buy another down the line. Thanks again for all of the input, everyone on yotatech is full of valuable info.
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