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High Idle + no Brake

1708 Views 4 Replies 2 Participants Last post by  lisekpl
2 Questions,
So I started the engine today after the timeserts and right upon startup it idles at 2 - 2.5k rpm and it doesn't go down. Does that mean I have a vacuum leak somewhere, and which hoses should I check?

and I think that this may have to do something with the vacuum leak, but I received a "Brake Booster Problem" message and I noticed that while pumping the brake pedal I feel no brakes. I know that the brake lines were disconnected but its as if the brakes are completely dead.
Again this is a 99 motor in a 96 body. Thanks in advance. Chris
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Is the vacuum line from the brake booster connected? That would cause no brake assist and a large vacuum leak.
Is the vacuum line from the brake booster connected? That would cause no brake assist and a large vacuum leak.
Yes, that is the first thing I checked. It's on there tight and I don't see any rips in it either. I know that when I first disconnected it I heard it hissing, but now when I disconnect it I hear nothing.
It's not getting any vacuum for some reason if it is silent when you pull the hose. Is there vacuum at the hose?
Ok, update. The vacuum leak was caused by a torn plastic boot on one of the vacuum hoses that run from the valve covers to the throttle body. The idle dropped maybe 500 rpm but still lingered around 2 k. In the end it turned out to be a defective IAC sensor valve, I extracted the little cylinder in it all the way out and the RPMs dropped to 1 k. I then adjusted it with the screw ro 750. For now it runs good, lets hope that that was it. Will check the vacuum booster tomorrow after the brakes are bled.
Again thanks Ranger for your input.
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