Aloha All,

I recently added some R134a freon to my system and did everything correct. Gauge in the green and the A/C blowing cold. The problem im having is that when im driving and start pressing on the brake or come to a complete stop, the engine starts to surge...

But when the A/C is not on, the truck idle is perfect and no surging what so ever. The last couple days i have been driving, I just click the A/C button off when coming to a stop lol.

My question is, has anyone experience this??? and if so, how did you fix it?

As far as im concerned everything is original and was retro fitted to r134a. A/C hasnt ran in this truck for atleast a couple years until I just added freon.

Any tips, tricks, or advice will help! Also I know i will probably have to replace the full ac system, anyone knows where I can buy a full kit?

Mahalo!

 

I've seen problems with the adjustment of the Idle up valve on the intake. (idle set too high) Also surging caused by the IAC valve sticking. But stepping on the brake makes me suspect a vacuum leak at the booster or hose. Turning off the A/C making the problem go away kind of rules this out though. Look into these three things I mentioned. Good luck with it and please follow up with what you find.

 

I have read many threads on this and still I have the same thing since I installed AC, booster isn’t leaking, no vacuum leaks. Same issue, brake pressed it surges with AC on but mine only does it when cold and warming up, once it gets warm all is good, which makes less sense I guess

I did have the surge all the time until I messed with the idle up adjustment, you may try that as suggested above as it’s the easiest thing to start with.

 

Whats up guys,

So this morning I did a cold start and immediately blasted the ac on high. No surging what so ever. I had it going for about 5 minutes before i noticed the ac clutch starts turning off and on (completely normal). Whole time ac is blowing cold.

Once the rpms went to normal, I pressed on the brakes and here comes the surge lol.

I went ahead and located the black knob which is the ac idle up valve. I went to turn it counter clockwise and noticed it was kinda seized/stuck. So i just wiggle turned it a few times and it budged. From its original position I turned it a couple times counter clockwise... went in the truck and pressed on the brakes. It kept doing the surge.

Then I turned it back clockwise to the normal position and pressed the brakes again... still surged.

I gave it three full turns clockwise and boom.... pressed on the brakes and the surging disappeared.

Turned it one time counter clockwise after. Pressed on the brakes and the surge is not there. Closed the hood, went for a quick 2 mile drive, stopped a few times, pressed on the brakes, and the idle is now perfect and no surge.

Basically gave my idle up valve two full turns clockwise.

Thank you discombobulated and aztoyman for the tips🤙 Now i can enjoy some cold A/C in this hot weather here in Hawaii.

 

Glad you got it sorted, I’ve learned to live with mine surging until warm. One day I may really dig into it…….one day

 

Thanks Discombobulated! Well when you get a chance to really dive into it I'd love to read about your diagnostics and learn from it.

On a side note, I can't imagine what it's like to have an old rig in the cold. Trying to get thee ol 22re to warm up must take awhile lol.

 

Its only when I have the AC on so it’s not a huge deal, these warm up pretty quick for their age, the fuel injection is a bonus on the super cold days and the cab is so small the heater turns atomic

Where you’re at do you ever need the heat? Man Hawaii is a pretty place, I went a very long time ago when I was 5 and I’ll never forget it!!!

 

Ahh I see! I also noticed that you you have yours garage kept so that must be really nice not having to shovel snow off the truck and stuff lol. How's the rust situation in the snowy areas? Here in Hawaii the salt water kills the yotas.

And never... you should come visit sometime! some of the old school yotas we have out here are insane. people do all kinds of builds. I have an 85 that i been wanting to swap to a 3.4 v6 engine from a 2004 tacoma