Newbie needs an answer! Please.

Hey guys! Brand new to board and seeking information. Have a 95 2.4 tacoma that has a disturbing idle issue. It's related to the times when the AC is on and the compressor comes on. When it does, hold on, cause the idle is WAY too high and the truck surges. On an old Corolla, I was finally able to locate a little device on the firewall that could be adjusted to that when the idle kicked up upon engagement of compressor, you could not tell the idle was increased and the ride became pleasant and not so dangerous.

I can't find the same device on the Tacoma. I thought it was the VSV (vacuum switching valve?) towards the firewall with the white painted adjuster that has a hex fitting. Moved it, nothing.

Someone knows how to do this. I've cleaned the throttle body, new gaskets including the Idle Air Control, so I'm certain that this is not it. Great improvements to drivability and idle, but the AC compressor surge thing persists.

Thanks so much!

JBeechcraft

 

Fast idle compensating for power loss incurred when the compressor was engaged, gonna be kinda hard to get around this one

 

Does it only do it for a minute or two or deos it do it constant as long as the AC is on?

 

How high of a rpm change?,,is it way out of spec?

 

Thanks for the responses! I certainly has to be out of specs in that when the A/C compressor kicks on, I have to hold tight on the brake to keep from hitting the vehicle in front of me. With AC off, the idle is just fine. Don't know what the actual rpms are as there is no tach in this base model.

I'm certain the functionality is fine, just need to set the idle back down to only compensate a little bit for the power loss when AC compressor comes on, rather than increase so much. It's not undriveable, just annoying and increases the risk for hitting someone/something when the AC compressor comes on.

All my prior Toyotas including a 22re and 2001 Corolla have some device that allows adjustment of the idle speed when compressor comes on. I just don't know where that device is on this truck.

Thanks for all the help so far!

 

I had a 91 4 runner it had a adjustment on the right front inner fender well. It was a small vacuum switch with a few small vacuum hoses on it with a small plastic knob on top of it to adjust the a/c idle.

 

Ok now I understand what your issue is because mine did that too....I think its normal. Mine does it with just the damn defrost turned on. Ill be at a red light and once it kicks in, i lunge forward about 3 feet. My RPM goes up to 3k - 3.5k but then it drops back down after 20 seconds more or less. My problem though was my brakes. I had to get my brakes re-bled because I had air in the brake lines. After that, no more forward lunge -but my rpm still jumped to 3.k + or - when defrost kicked in. Just my 2 cents hope this helps.

 

Yes Pakrat, you're getting close. All the previous Toyota vehicles I've owned had some form of device that permits you to adjust and compensate for the minor power loss from the AC compressor kicking on. When adjusted properly, the compressor can kick on and off with no discernible change in RPM. As it sits, when the compressor kicks on the truck lunges forward because the setting is too high. This is NOT the AC amplifier switch behind the glove box on similar 22RE motors. This is a different to me Tacoma with 2.4 and actually the same year as my 22RE truck. Personally, that 22RE truck in my opinion, is the best darned truck make. I've had probably 10 of them over the years and this is the first Tacoma which is a bit quirky to me. Assembled in Canada I guess. Love the Japanese models - the quality is amazing!

Thanks to all who have attempted to help. Someone knows this and where the device is located. I'll just have to be patient. I can't seem to find anything on the Internet either and it's not a deal breaker, but very annoying.

Thank you!