Shaggy_TSi Posted March 22, 2008 Report Share Posted March 22, 2008 Didnt want to post it on Virtual Mechanic cuz i dont think its that important Anyways, whats the black little motor (that i think its vacuum) behind the coolant bottle? again(same as the A/C compressor) its still on even with the car turned off. Thanks Link to comment Share on other sites More sharing options...
JAinsworth Posted March 22, 2008 Report Share Posted March 22, 2008 It is the vacuum pump. Should have a line running frm it to the cannister near the ABS. Jimmy Link to comment Share on other sites More sharing options...
Shaggy_TSi Posted March 22, 2008 Author Report Share Posted March 22, 2008 Hmmm ill check if a vaccum line got loose... think thats whats making it not turn off? Link to comment Share on other sites More sharing options...
Shaggy_TSi Posted March 22, 2008 Author Report Share Posted March 22, 2008 yup, thats what it was... found the line, now it turned off Thanks Jimmy! Link to comment Share on other sites More sharing options...
shift1313 Posted March 23, 2008 Report Share Posted March 23, 2008 hey jimmy, is the vac pump only used for the cruise control? i cant remember Link to comment Share on other sites More sharing options...
JAinsworth Posted March 23, 2008 Report Share Posted March 23, 2008 And a/c iirc. Jimmy Link to comment Share on other sites More sharing options...
Laodicea Posted March 23, 2008 Report Share Posted March 23, 2008 Oh so that is why i get no ac or heater in vents on boost. Link to comment Share on other sites More sharing options...
mikec Posted March 23, 2008 Report Share Posted March 23, 2008 The vac pump is for the cruise control only. It only gets power when: 1: cruise control system is turned ON via the steering column switch 2: pressure sensor in the back corner of the firewall (next to wiper motor) senses low vacuum and/or boost pressure. The sensor trips a relay that in turns powers the vac pump. The dash vent vacuum circuit is isolated from the cruise circuit via 2 little white check valves. These are located in the vac hose maze/mess near the wiper motor. One allows vacuum into the vent actuators and the cruise circuit; this valve is basically hooked into the main source of vacuum: the port on the throttle body below the row-of-three. The other check valve isolates the cruise from the vent circuit. Air should flow only one way through the check valves - basically towards the intake manifold vac port. For the dash vents, the vacuum collects in that black tank/canister next to the ABS claptrap. With the engine off, remove the vac hose on the top of the tank. Did you hear a "whoosh" of air filling the vacuum in the tank? If not, you've probably got a vac leak under the dash. The "face/foot" actuator commonly develops a leak. Crawl under the dash, on the driver side. Remove the carpet panel on the console (next to the stereo) and the "knee panel" underneath the driver side of the dash. You'll see a maze of wires, the ducting for the heater/vent airflow, and a couple gold colored actuators attached to the white plastic housing of the heater/vent system. One actuator will be mounted vertically - and will be closer to the firewall. That's the defrost one. The other is mounted horizontally, closer to the stereo. Look at the pushrod coming out of it (pointing towards the firewall) and you'll see a rubber bellows on it... that bellows splits/tears and causes a vac leak. As long as the engine is running off-boost (i.e. vacuum is present) this actuator does its job... but on-boost the "trapped" vacuum in that black tank/canister holds the actuators. If the actuator leaks though, the canister runs out of capacity (it's a vacuum reservoir) and the face/foot actuator drifts. To remove the actuator: have plenty of time & light available... it's a pain the first time. On the pushrod end, undo the two itty-bitty screws. Very soft heads... and very tight screws. Don't be surprised if the heads want to strip out. Do NOT follow the linkage and figure "I'll just undo it at that phillips screw with the white collar" - it looks so easy... a whole slew of linkage parts and springs will fly out. You'll have a puzzle if you remove that one stinkin' screw. Once the two itty-bitty screws are out, undo the two screws holding the actuator to the mounting bracket. You might need needle-nosed vise grips to break them free, or an offset/racheting screwdriver. These screws are also soft-headed (like all Mitsu's gold screws used on interiors... they suck) and tend to be really tight. Then undo the two vac hoses (one on each end) of the actuator. Don't loose them; and mark them so they go back the same way they came off. With the actuator in hand, examine the bellows for splits/tears. If the tear is small - and concentrated in one groove of the bellows - you might get lucky with 2-part epoxy. Clean the bellows completely, and then wipe it with alcohol followed by water to really clean it. Mix up a little two-part epoxy and smear a bead across the split... wrapping the bead all the way around the bellows. A "ring" of epoxy seems to grip longer than a small split-filling blob. By the way, that actuator is not available new any longer - or so I've been told. It's worth grabbing decent ones from parts cars or junkyards. mike c. Link to comment Share on other sites More sharing options...
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