97ranger11
Member
- Joined
- Aug 2, 2013
- Messages
- 65
- Reaction score
- 2
- Points
- 8
- Vehicle Year
- 1997
- Make / Model
- ford
- Transmission
- Manual
Does anyone have a wiring and vacuum diagram for hvac?
Cliffs through post 4,
CLIFFS
I'm thinking blend door actuator is not routing air through evaporator causing low side pressure to rise till switch disengages clutch. And a coincidink of a bad pressure switch.
97 2.3l ranger
So, I've traced all the heater related vacuum lines from the intake manifold to the dash and can't find any visual issues, however if I soak the area just to the passenger side of the EGR valve Idle bumps from 800rpm to 900-950rpm, so I imagine there is a small leak in that area.
So this truck has always had a rev hang. I just let it be, with all of the current issues I suspect it's vacuum related. A few months ago air started stopping coming out of the vents at random. It'd happen then fix itself repeat etc. I never checked but I assume it defaulted to defrost. That's got a lot worse recently, only it only happens when I have it set to heat (so when cold in morning). Haven't had it do it with the AC in a while.
Now the real problem, AC stopped working. Well now it doesn't work at all, before it worked some of the time gradually decreasing to none of the time. The one time I got gauges on it when it came on (recently that is) the low side pressure spiked up to 100+ psi before kicking off the compressor. High side didn't excede 150psi I don't think. The clutch coil isn't getting power, fuses are good, and I don't suspect wiring issues. A year ago it got a new compressor, condensor, orifice tube, accumulator, and a good flush and has been ice cold since. I don't suspect a leak. I immediately think pressure switch given everything I replaced, but can't help but wonder if it is vacuum related.
Thoughts?
Edit: thinking about it, I wonder if it is not diverting air over the evaporator causing the low side pressure spike? Doesn't explain why the compressor is no longer kicking on at all though.
Cliffs through post 4,
CLIFFS
- air sometimes only blows through defrost vents
- a.c went from working to working intermidently to not working at all
- when the ac would come on just before it stopped coming on at all, low side pressure would spike see https://youtube.com/shorts/FMTw_N00IUs?feature=share
- 2 years <1k miles on new compressor, condensor, accumulator, evap flush
- relay socket getting constant and trigger power, tried swapping relays
- both switches 14v in/out
- clutch coil not getting 12v
I'm thinking blend door actuator is not routing air through evaporator causing low side pressure to rise till switch disengages clutch. And a coincidink of a bad pressure switch.
97 2.3l ranger
So, I've traced all the heater related vacuum lines from the intake manifold to the dash and can't find any visual issues, however if I soak the area just to the passenger side of the EGR valve Idle bumps from 800rpm to 900-950rpm, so I imagine there is a small leak in that area.
So this truck has always had a rev hang. I just let it be, with all of the current issues I suspect it's vacuum related. A few months ago air started stopping coming out of the vents at random. It'd happen then fix itself repeat etc. I never checked but I assume it defaulted to defrost. That's got a lot worse recently, only it only happens when I have it set to heat (so when cold in morning). Haven't had it do it with the AC in a while.
Now the real problem, AC stopped working. Well now it doesn't work at all, before it worked some of the time gradually decreasing to none of the time. The one time I got gauges on it when it came on (recently that is) the low side pressure spiked up to 100+ psi before kicking off the compressor. High side didn't excede 150psi I don't think. The clutch coil isn't getting power, fuses are good, and I don't suspect wiring issues. A year ago it got a new compressor, condensor, orifice tube, accumulator, and a good flush and has been ice cold since. I don't suspect a leak. I immediately think pressure switch given everything I replaced, but can't help but wonder if it is vacuum related.
Thoughts?
Edit: thinking about it, I wonder if it is not diverting air over the evaporator causing the low side pressure spike? Doesn't explain why the compressor is no longer kicking on at all though.
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