Engine code 25 and 26
07-19-2008, 05:55 AM
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Engine code 25 and 26
I finally got an engine code.... 25 and 26.
The manual says its (for 1995 V6 4Runner):
Here is my symptom.. Lack of power on the interstate... or lack of power in general.. I'm guessing its MAF or some fuel related..
What I've done so far.. All new ignition wires, sparks, cap, etc..
New fuel filter, old one was ok.. Timing belt was changed 30K miles, Everything works only lack of power..
Check the Cat and cats fine. I guess it could be the O2 sensor...
Anyone with similar problem and could give me a better idea what part might be bad?
The manual says its (for 1995 V6 4Runner):
Here is my symptom.. Lack of power on the interstate... or lack of power in general.. I'm guessing its MAF or some fuel related..
What I've done so far.. All new ignition wires, sparks, cap, etc..
New fuel filter, old one was ok.. Timing belt was changed 30K miles, Everything works only lack of power..
Check the Cat and cats fine. I guess it could be the O2 sensor...
Anyone with similar problem and could give me a better idea what part might be bad?
07-19-2008, 06:08 AM
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yep... it's got a list of probable causes of the two conditions, so there's a starting point.
but considering you're getting both lean and rich errors, I'd say start with checking the AFM and then the O2.
but considering you're getting both lean and rich errors, I'd say start with checking the AFM and then the O2.
Last edited by abecedarian; 07-19-2008 at 06:12 AM.
07-20-2008, 10:56 AM
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I've got same issue.
Had it since dealer worked on my car (head gasket recall), but car was always running lean. Anyway, I replaced both O2's (one was bad), but it didn't help. Been playing around with everything. VAF (Volume air flow) sensor reads a little low, but not too far off. I tampered with it according to the instructions on the Downey web site, and it helped a little, but gave me the rich code. From recent fiddling, and some improvement, I think it may be an intermittent vacuum leak. More air leaking in would cause lean condition. One possible source is the idle air control valve which is part of the throttle body. The FSM is not clear about how to test this.
Other possibility: bad fuel pressure, as the book says. Unfortunately, there's no easy way to test it without a special adapter to hook up the gauge. You can test the fuel pressure regulator VSV (vacuum servo valve), which I did. Before you do, listen for a pulsing sound coming from the fpr, which is good. I also tested the cold start injector time switch and the coolant temperature sensor with an ohmmeter. These are hard to reach.
My next step: replace PCV with oem unit and a new hose, to eliminate that as a possible leak or malfunction. It's cheap. Hope this helps a little.
Question: Does anyone know a way to test the fuel pressure without buying special Toyota adapters?
Other possibility: bad fuel pressure, as the book says. Unfortunately, there's no easy way to test it without a special adapter to hook up the gauge. You can test the fuel pressure regulator VSV (vacuum servo valve), which I did. Before you do, listen for a pulsing sound coming from the fpr, which is good. I also tested the cold start injector time switch and the coolant temperature sensor with an ohmmeter. These are hard to reach.
My next step: replace PCV with oem unit and a new hose, to eliminate that as a possible leak or malfunction. It's cheap. Hope this helps a little.
Question: Does anyone know a way to test the fuel pressure without buying special Toyota adapters?
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