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Discussion starter · #21 ·
You sure? Because if I put the car in drive and I turn on the headlights the rpm goes up and down like it's losing power. Also, for my model I don't think I have a brake booster. Or where is the brake booster located?
 
On the firewall directly on the opposite side of where the brake pedal is.
 
You sure? Because if I put the car in drive and I turn on the headlights the rpm goes up and down like it's losing power. Also, for my model I don't think I have a brake booster. Or where is the brake booster located?
Yes I am sure and it makes a lot of sense. I believe you have a bad booster or a vacuum leak associated with the line running from the manifold to the booster. Your brake fluid reservoir is on the master cylinder and that is attached to the booster which is mounted on the back engine firewall (bulkhead).
A vacuum leak would also explain why the engine falters when the alternator resistance increases under load (light on, etc).

I would change my strategy. Start with the intake manifold. Check the hose running to the booster and go from there.

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Discussion starter · #24 ·
My egr valve is on the left-hand side of the car and my brake fluid cap is on the right-hand side. I'll check to see if there is a brake fluid line. I did had 2 codes that were p0401 I changed the egr valve and that went away. I also had p2187 system too lean at idle. I blow smoke in a vacuum line and smoke was coming out where the oil dipstick is. I changed the dipstick cleared the code and the code didn't show up again.
 
Discussion starter · #27 ·
I will smoke it out again. Thanks for your advice. I appreciate it. I will check the brake booster line to see if there are any cracks. Question if I smoke it out shouldn't smoke come out of the intake manifold?
 
I don't think I have a bad booster because before I start up the car I keep pressing the brakes and the brakes get hard and when the car starts the brakes go down easily.
He said booster problem, not a bad booster, so the HOSE can be bad. Smoke wont come out cause its under vacuum, not pressure.
 
Discussion starter · #29 ·
I have done extensive checks with the brake booster hose. I sprayed soapy water on it to see if there were any bubbles. I check the hose for cracks I saw no cracks. I started the car and then shut it off and press brakes and hold the brakes for 30 seconds and the brakes didn't go up. I pump up the brakes to get hard and started the car and it gradually went down.
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I heard the hissing, but didnt detect any difference in the tone in the first vid.
 
Discussion starter · #34 ·
The first video it sounds like it's jumping when I turn on the headlights and I don't know if you can see the rpm slightly going up and down. On my scan tool it can go from 700 to 580rpm up and down. But when I turn off the light it's in the range of 650 to 700rpm.
 
Something occurred to me earlier, are you doing all these measurements at idle? Alternators put more out while driving than at idle. The 1st Gens dont have the variable voltage the 3rd Gens do.
 
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