Notices
86-95 Trucks & 4Runners 2nd/3rd gen pickups, and 1st/2nd gen 4Runners with IFS
Sponsored by:
Sponsored by: DashLynx

No high idle with AC on?

Thread Tools
 
Search this Thread
 
Old 08-28-2015, 05:45 PM
  #1  
Registered User
Thread Starter
 
lethe's Avatar
 
Join Date: Mar 2006
Location: everett wa
Posts: 133
Likes: 0
Received 1 Like on 1 Post
No high idle with AC on?

I recently lost high idle when i turn on the AC in my 91' 3.0 4runner. I installed a ebay special air intake and it seemed to have stopped working shortly after that. The compressor clutch still engages so i'm assuming that isn't the issue. Does anyone know controls the high idle function on these?
Old 08-28-2015, 10:32 PM
  #2  
Registered User
 
horunner1x's Avatar
 
Join Date: Oct 2014
Posts: 96
Received 4 Likes on 4 Posts
There's supposed to be a separate idle screw I think. There's one on the 22re so I figure one should be on the 3.0 too. Both same years and whatnot. The ones on the 22re are a black box with an idle screw coming out of it with vac lines. Look around for that.
Old 08-28-2015, 11:33 PM
  #3  
Registered User
 
AKHeathen's Avatar
 
Join Date: Aug 2015
Location: Anchorage, AK
Posts: 435
Likes: 0
Received 1 Like on 1 Post
the vsv is located on the passenger side fender well, below the diag connector i'm not 100% sure which one it is for the ac, but you should be able to determine by wire color.
Old 08-29-2015, 06:08 AM
  #4  
Registered User
Thread Starter
 
lethe's Avatar
 
Join Date: Mar 2006
Location: everett wa
Posts: 133
Likes: 0
Received 1 Like on 1 Post
I'll take a look in a bit. Since it was working fine an then stopped suddenly i was thinking it was electrical?
Old 08-29-2015, 08:15 AM
  #5  
Registered User
 
scope103's Avatar
 
Join Date: Sep 2007
Location: San Francisco East Bay
Posts: 8,254
Likes: 0
Received 822 Likes on 649 Posts
Originally Posted by lethe
... I installed a ebay special air intake and it seemed to have stopped working shortly after that. ...
The ECU actuates a VSV when the AC clutch is actuated. http://personal.utulsa.edu/~nathan-b...23vacuumho.pdf The VSVs are mounted on the right apron: from the back they are PAIR, FPR, EGR and AC. If you have ADD, there are two more VSVs forward and to the right of the AC VSV. The manual gives the testing procedure, and the drawing of the actuator will help you locate the correct VSV.

The AC (and Power Steering) idle-up gets filtered, atmospheric air from the "resonator"' below the VAF. I don't know what an "ebay special air intake" is, but if it's what I think it is, loss of AC idle-up is just the beginning of your problems.
Old 08-30-2015, 05:44 AM
  #6  
Registered User
 
AKHeathen's Avatar
 
Join Date: Aug 2015
Location: Anchorage, AK
Posts: 435
Likes: 0
Received 1 Like on 1 Post
it didn't happen to delete the side chambers and piping with the new kit, did it?
Old 08-30-2015, 07:16 AM
  #7  
Registered User
Thread Starter
 
lethe's Avatar
 
Join Date: Mar 2006
Location: everett wa
Posts: 133
Likes: 0
Received 1 Like on 1 Post
This is a random internet picture but it looks similar to this except the pcv is vented to atmosphere and there is a second air hose pre maf connected to the hard line that's capped in the picture.


Old 08-30-2015, 09:53 AM
  #8  
Registered User
Thread Starter
 
lethe's Avatar
 
Join Date: Mar 2006
Location: everett wa
Posts: 133
Likes: 0
Received 1 Like on 1 Post
Originally Posted by scope103
The ECU actuates a VSV when the AC clutch is actuated. http://personal.utulsa.edu/~nathan-b...23vacuumho.pdf The VSVs are mounted on the right apron: from the back they are PAIR, FPR, EGR and AC. If you have ADD, there are two more VSVs forward and to the right of the AC VSV. The manual gives the testing procedure, and the drawing of the actuator will help you locate the correct VSV.

The AC (and Power Steering) idle-up gets filtered, atmospheric air from the "resonator"' below the VAF. I don't know what an "ebay special air intake" is, but if it's what I think it is, loss of AC idle-up is just the beginning of your problems.
There are still air lines connected from the air intake to the hard lines at the manifold. They are pre maf/vaf though. Maybe it's not enough air flow? The a/c switch is working and sends power to the vsv plug. I'm thinking it's either a air flow issue or the vsv is bad. I'll check the vsv as it describes in the link you posted.
Old 08-30-2015, 11:06 AM
  #9  
Registered User
Thread Starter
 
lethe's Avatar
 
Join Date: Mar 2006
Location: everett wa
Posts: 133
Likes: 0
Received 1 Like on 1 Post
Update: Checked the vsv and it is working properly. I checked it by connecting it straight to the battery and with it connected to the harness. It's open and closed when it should be and air flows freely through it when it's open.

The air line coming off the air intake pulls vacuum when the vsv is activated so i'm not sure what the problem is. Adjusting the black knob on the vsv does nothing.
Old 08-30-2015, 03:33 PM
  #10  
Registered User
Thread Starter
 
lethe's Avatar
 
Join Date: Mar 2006
Location: everett wa
Posts: 133
Likes: 0
Received 1 Like on 1 Post
I used some left intercooler piping and couplers from a past project and moved both air lines from pre vaf to post vaf. High idle now works again when the ac is turned on.

After learning how the how idle works on this engine i realized that having the air lines located in front of the maf was pulling un metered air into the engine. Which probably explains why it would have a bit of a rough idle before i switched the line location around.
Old 08-31-2015, 05:06 AM
  #11  
Registered User
 
AKHeathen's Avatar
 
Join Date: Aug 2015
Location: Anchorage, AK
Posts: 435
Likes: 0
Received 1 Like on 1 Post
cool beans, that smaller hose in the pic is post vaf, and the larger (capped off) in the resonator, pre-vaf
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
tomczaksdiesel
86-95 Trucks & 4Runners
0
07-26-2015 10:35 PM
Cbr954ryder
Newbie Tech Section
0
07-25-2015 06:32 PM
greenbuggy
3.4 Swaps
4
07-23-2015 11:51 AM
luckypig44
Newbie Tech Section
4
07-19-2015 11:25 AM
kyletbert
86-95 Trucks & 4Runners
3
07-17-2015 11:39 AM



Quick Reply: No high idle with AC on?



All times are GMT -8. The time now is 08:52 PM.