any suggestions? I tried a whole can of foaming engine degreaser, and it didn't seem to fix a thing.

update - tried getting the master cylinder replaced but couldn't disconnect the hydraulic line . . . I figure I'll try some liquid wrench for a couple days. If that doesn't work I may just have to cut the line, and get a replacement.

Still trying to get the AC fixed. Can't find the tube NismoPick was talking about. Do I have to take apart the dash?

 

Looks like you are going to have to get your hands dirty with that engine bay. Spray and scrub and scrub some more

Pull the radio console out of the dash, the vacuum lines are right in that area.

 

There is one vacuum line that goes from the vacuum canister at the engine bay light, through the firewall by the battery. Look for the grommet in between the battery tray and cylinder head. ( I drew a line on your pic of where it is).

As for degreasing... I use the cheap Autozone stuff (http://www.autozone.com/autozone/acc...fier=7710_0_0_)

Spray it on a warm (not hot) engine, let it soak in, and spray it off w/ water. Repeat until clean. For heavy grease areas, you will need a tooth brush / gasket scraper.

Before starting the car, disconnect the TPS plug & blow dry. Do the same w/ the distributor cap.

 

update again . . . with lots of pics.

trying to fix the high-idling issue and the A/C are perhaps just making things more confusing.

So, I looked at the A/C vacuum tank and this is what greeted me:


from what I can tell from the FSM, #1 is supposed to connect with something called the vacuum selector. #2 is supposed to go to the intake manifold. #3 is supposed to go somewhere else on the intake manifold. The problem? I don't know what a vacuum selector looks like or where it is located. #1 ends up here:

and I couldn't find it inside the car. I am really inept... I don't know what the vacuum selector looks like.

#2 has nothing but a broken off piece of vacuum hose. I have a replacement hose, but I have no idea where in the intake manifold I am supposed to plug it in. #3 ends up here, where it splits:


and ends up plugging into something to do with cruise control:


and nowhere

Again, I have extra hose, but I don't know where in the intake manifold it is supposed to go.

Also, I replaced the CHTS, but the car is still idling high. around 1300 when cool, about 1500-1700 when warm or hot. I tried to find the screw to adjust the idle speed, but . . . I couldn't. According to the Haynes manual picture, it should be here:

but I didn't see anything that looked like their picture. I will search in the forums and see what else I can find about high-idling. I was really hoping it was just a bad CHTS.

The good news? the engine bay looks a little better after 4 cans of degreaser!

 

Indeed that engine bay looks a lot better.

The vacuum selector is your a/c / heater vent selector on the dash board.

Notice the doubled up hose that I circled in your pic? Both of those are for the vacuum tank. The lines connect to those intake ports.

 

I am once again in awe of your knowledge.

That explains why I was not able to find anything on the intake manifold that didn't have a hose attached to it. So, those aren't supposed to be connected to each other at all? (I mean except through the vacuum tank). Is the vacuum tank supposed to be connected to the cruise control as well? Or is that just another creative connection from the previous owner?

 

Check page 212 in the Haynes manual (lower fig 10.20). That is the vacuum diagram for the engine bay... it's not 100% accurate (missing the 2nd intake port & the line to the a/c). The a/c vents & cruise control are both fed by the vacuum tank. You can run vacuum right from those manifold ports, but at full throttle, there is no vacuum in the intake, so your a/c vents will flop closed to default (defrost & floor).

 

Thank you for pointing out that diagram!! I tried to find something like that, but never thought to look in the cruise control section. Between that page and HA-10 of the FSM, I was able to get things hooked up correctly (I think). I really think the last person to work on the system just started plugging vacuum hoses wherever they wanted.

However, I still have the problem with the vent switching to floor at full throttle. Honestly, I'm just happy at this point to have it blowing on me most of the time. I think I will try to upgrade to R134a to get it a little cooler.

Also, I am not sure it is related to switching around the vacuum hoses or just an improvement from the new CHTS, but my idling RPMS have also dropped a bit. Today it was down to about 1000 rpms when cold and 1100-1200 rpms when warm. hopefully this helps my gas mileage. I will be checking the air regulator next to see if it is working correctly.

going back a bit to the hazard flasher. I found what I think is the wiring for the hazard relay, but it just doesn't match the part I got from autozone. I will try to upload a picture of the connector I think it is.

 

I wouldn't convert to R134a if your R12 system is still working. R134a is less efficient (creates more heat). You might want to pull the vacuum canister & check for cracks.

 

well, the A/C was blowing out of the vents just fine until today. Now it is blowing maybe 1/3 out the vents and 2/3 out of the floor vents. I'll recheck that the tubes are connected correctly. I saw in another thread the recommendation to cut vacuum lines back about a half inch and reconnect them. That might be my next course of action.

Also, I looked over the vacuum canister and didn't see any visible cracks.

 

You can check to see if you're not getting enough vaccum just by disconnecting the line and sucking on it and see if the vents line up properly. If they don't then there is a leak inside the climate control system - either a cracked line, loose fitting, the vaccum switch, vaccum servo, etc....

 

And now there is a new issue. I was sick for a couple days, so the zx was just sitting. Went to start it this morning and the battery was mostly dead. I had to get jumper cables just to get it started. anything that is a notorious slow power leak that I should keep an eye out for?

 

Could be a weak battery... can you see on the sticker when it was produced?

The only "classic" drain problems would be from a stuck door pin, radio wired direct to battery, or some random mis-wiring.

 

I've noticed that the voltmeter on the dash is usually right below the red when the car is running. Is that fairly normal?

I had the battery tested and deep charged right after I purchased the car, so it shouldn't be dead already. I will double check the date to make sure.

There was a radio wired directly to the battery, but that was removed before I purchased the car. I removed the wiring for the radio a couple weekends ago. The door pins seem to be fine. The light turns off when the doors are closed.

I guess it is just a random mis-wiring then... that should be fun to try and track down.

 

Should be @ 14V when running. If not, your alternator isn't charging or the battery wiring is corroded / faulty. Might want to stop by AutoZone and have them do a free alternator load test.

 

I will have to do that tomorrow. in the meantime here is a video of the voltmeter.

http://www.youtube.com/watch?v=TddAWwdTDwQ

also, I noticed when the A/C turns on, the RMPs drop by about 200RPMs temporarily, and the voltage drops at the same time. I don't know if it is related, but there is that odd sound when the A/C is turned on and off. I'll update again tomorrow after the alternator load test.

 

Maybe your voltage regulator in your alternator is faulty. My Z's have never read past 14 while running. So hopefully when you have it tested at Auto Zone. They will find the culprit for you. Good luck man.

Of course since I installed the hand clock (analog) The volt gauge always reads 12volts, while the car is running. I find that strange, but am thinking either the clock takes more juice to run. Or my gauge is faulty.

 

Just watched that video... I thought you meant the "low" side red. Your alternator might be putting out a bit too much juice, but it still looks okay to me. We'll see what AZ says.

As for the noise when the a/c is turned on, that's either a vacuum port noise on the intake manifold, vacuum canister, or it could be the expansion valve (under the dash). Have somebody turn it on & off while you listen, so you can pinpoint the location.

 

Get a real volt meter and check it. The stock one can easily be out by a fair amount..

 

Took the car to Autozone and did the alternator load test. They said that it passed just fine. I haven't had the problem since, so I am hoping that it was just a one time problem.

@ FricFrac - the reason I've been trusting the voltmeter in dash is that I have compared it to a real one before when I was first working on the car, and it was always pretty accurate. That is always a good thing to check, though.

 

So, I went and replaced the vacuum lines in the engine bay to try and get the A/C and vents to work correctly; I ran into some more issues.

Current rundown.

A/C still blows cold air. this makes me happy. But if you put the A/C on the dash vents, it blows on your feet 100%. If you put it on the foot vents, it blows 100% on your feet. On A/C mixed vents, it blows 95% out of the dash vents and 5% out of foot vents. I am fine with this for now. I mostly just keep it on the mixed vents.

The real issue, in my eyes, is that I can't get the defroster vents to work. No matter what I set the selector to, It will only blow out of the dash vents or the foot vents. Any suggestions? Or do I just need to take apart the dash and replace ALL of the hoses?

Engine is still idling high, and I am still getting terrible gas mileage (about 15 mpg). I've got a spare air regulator and cold start valve, so I will replace those today or tomorrow. I guess the next step (if those don't work) is trying to replace/fix the fuel injectors.

I still can't get the stupid nut off of the master cylinder. I've tried PB Blaster, and WD40. any suggestions? I'm tired of refilling the hydraulic fluid every other week.

 

There is a lever on the drivers side knee panel for the floor vents. Is that open? Other than that, I imagine one or more of the vent door actuators is either stuck, or just not receiving vacuum. Or the foam insulation between couplers has fallen out allowing all the air to escape. Pulling the dash isn't hard, just time consuming. We even had a recent detailed thread on it.

Low mpg could be several things. Did you ever get the CHTS figured out?

For the master line, did you clamp on a pair of vice grips? You will likely destroy the edges, but that is about the only way to get it off / back on.

 

NismoPick- The lever you mentioned, is that the one that says something like "pull to open" and has two vacuum lines coming off? If so, the vacuum lines from the lever have come disconnected. I couldn't figure out where it was supposed to connect to, so I haven't touched it. I will try to get that figured out next. I saw that thread about the dash, and will definitely be using it if I end up having to take it all apart. I also noticed that FricFrac replaced that black disintegrated foam with some nice white insulating foam in his most recent project. I might try to do the same.

I did get a new CHTS from MSA and it helped with the RPMs and gas mileage a bit. It dropped RPMs by 300-500, and improved gas mileage from 10 mpg to 15 mpg. Still a ways to go before I hit the factory 30 mpg. When I searched the forum, it seemed like the most common suggestion after checking the CHTS was to check/replace the cold start valve and air regulator. Especially because I have also been having issues with cold starts.

Thanks for the suggestion on the master line! I will have to try this. It is nice to know that I am not the only person to have had this problem, though.

 

There's the problem (or a major part of the problem anyway).

Two disconnected vacuum lines = big vacuum leak. Vacuum leak = vent doors don't function.

Just pull that kick panel (2 phillips screws) & reconnect the lines to the ports on the switch (or block each tube, or tie them in together w/ a butt connection).

Have you pulled your spark plugs to read the tips recently?

 

Thanks for the heads up. I had no idea that the pull lever was at all related to the vacuum system. I could have worked on it for a million years and probably never gotten that. Spent a while poking around after I reconnected that one, and found that some of the other vacuum lines had come disconnected as well. Hooked everything back up, and now it works perfectly! I think I still might go in and replace the vacuum lines, though. It seemed like the one I put back on was stretched and that is why it fell off.

I swapped out the air regulator, and cold start valve. The cold start valve in my car was absolutely filthy with carbon buildup. Sadly, no real change in the idling speed, though.

I put in new spark plugs when I bought the car 500 miles ago. I haven't checked them since then.