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Ps ans Ac Idle up 1HDFT


New Member
Apr 15, 2023
Country Flag
Hi there everyone! New member here. This is an old thread but help would be appreciated.

I own a 1HDFT H151f 80 series. The car was stalling a lot, especially at stops and stationary turning of the wheels. I did some research and checked my PS and AC idle up calibration. To my surprise the AC idle up vacuum hose had been unplugged, I plugged it back in and immediately the rod pulled back in and my idle went up to 850. So it all went well!

I drove the car with the Ac on and it didn't stall however turning the steering stationary caused it to stall. I checked the PS vacuum hose at the opposite end of the AC hose and it felt like it was there. I traced my finger along it and I turns out the hose had been cut off and it was squeezed so tightly that there wasn't any vacuum leak.

If you've read this far please bear with me.

1) I don't know where to plug this end of the hose to. So any help would be great help. I've looked at the 1hdft vacuum diagram but im guilty of not being wise enough to understand.

2) Secondly I blocked this hose off with a screw to prevent any vacuum leaks but now my AC idle up isn't working anymore either, as in the rod isn't pulling itself back anymore.

There is vacuum in the VSV, there is vacuum at the opposite open end of the PS incomplete hose. But it isn't still working. Any thoughts?

Any help would be of great value and cheers in advance to anyone willing to help out