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- #21
I didn’t remove it I probed the wires and ran the engine, saw the vincease as temp went up steadily
80 series bad idle, sluggish acceleration when cold (2 Viewers)
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- #22
Just found out…… that I can check codes when it isn’t showing a CEL! I am getting 24 and 31 which is VAF and IAT!! And getting 21 and 28 which is o2 sensors, but no CEL while driving!
Will start my investigation here
Will start my investigation here
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- #24
Not for 20min just for 5 or so! I will pull it now for 20!
there are some obd 1 scan tools, I use my launch and snap-on regularly for OBD1 Toyota. There are much cheaper options that would be good for a DIYer like toyocom or I'm sure there are others out there. There is a few tests you can do with a multi-meter on the obd1 port too. Breakout box is nice but you can do all the same tests with back probing at the ECU too.
Something may have happened to the connections at the airflow meter.
Moving the lid around could have affected those 31year-old wires.
Moving the lid around could have affected those 31year-old wires.
ok, so it would seem the codes are current, and still active, since they are unable to be cleared. I'd be looking at your VAF again. These are notorious for being problematic, especially after being cleaned or disconnected, given their age. Do you have access to another? (I know, it's a long shot)
For codes 21/ 28 are usually the heater circuit inside the oxygen sensors. Iirc 6 ohms is the spec. Also check for voltage for both heaters. Repair this first and then go after the other two. For 24/ 31 sounds like you're going to need a AFM, Make sure the boot is not torn or cracked between air flow meter and throttle body.
Having a similar issue myself and will be/have been trying several things mentioned.
Truck was running fine and had Code 26 (Running Rich) show and the same stuttering and RPM issues mentioned began. I changed the O2 sensors with 89465-69115 that the previous owner gave me. The wire connector plastic had two ridges that didn't match the receiving end of the connector but I wiggled it in eventually. Truck ran perfect afterwards for about 2 weeks. Then the code comes back intermittently along with the idle and RPM issues. Sometimes the code will pop about 5 minutes into driving and the side effects begin but then will go away after 10 minutes. I will also mention the first time the code came on it had gotten really cold and has been really cold since. I do notice when the temp jumps up for a day or to that the issues seem not as bad or don't show at all.
If anyone has any other suggestions please let me know.
Truck was running fine and had Code 26 (Running Rich) show and the same stuttering and RPM issues mentioned began. I changed the O2 sensors with 89465-69115 that the previous owner gave me. The wire connector plastic had two ridges that didn't match the receiving end of the connector but I wiggled it in eventually. Truck ran perfect afterwards for about 2 weeks. Then the code comes back intermittently along with the idle and RPM issues. Sometimes the code will pop about 5 minutes into driving and the side effects begin but then will go away after 10 minutes. I will also mention the first time the code came on it had gotten really cold and has been really cold since. I do notice when the temp jumps up for a day or to that the issues seem not as bad or don't show at all.
If anyone has any other suggestions please let me know.
I would double check your O2 sensors. I went through 2 sets of Denso 95 spec an NTK that was supposed to be for a 93-94 and it still ran poorly. I ended up buying NTK sensors off Amazon that fixed my problem. Check the O2 sensor voltages and make sure they are switching properly.
What year is your cruiser?
It's a '94
Will do. That is next on my checklist, thanks for the recommendation.
Old Nick
GOLD Star
I would buy oem O2 sensors and relocate them to the manifold. That sorted out rough running and codes in my wife’s 94.
Leave the current bungs in place and pull the connectors into the engine bay. Wrap the wiring in heat/fire proof wrap, install the new oem sensors.
The relocation requires delete of the PAIR system. So, if you have yearly smog, this probably won’t work for you.
CharlieS
GOLD Star
Good luck finding genuine OEM O2 (NTK) sensors for a '94. I looked for a long time and failed. I have a set on the shelf from Amazon that are allegedly NTK, but I'm convinced that they're knockoffs. I compromised and the Densos have worked well for me.
You can check the oxygen sensor signal right at the diagnostic box on the firewall, OX1/OX2 to ground around 1500 RPM and engine coolant temperature 185 F, that would be my other question, do you happen to have a thermostat that's operating correctly 185F.
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Old Nick
GOLD Star
Only one of the oem sensors for the ‘94 is still available. I can’t recall if it was the long or short one. But Toyota still has them. When I relocated the sensors to the manifold (recently), I used the oem sensors and that still available x2.
The remaining OEM sensor can be used in both of the original locations.
