vacuum issues,....

[rush91]

So I went to start up this Beast this morning, and it started but immediately died. I cranked her again and fired right up.......I have been getting a flashing climate control button. Which I diagnosed was a freon leak. I talked to Marc H and he said he converted the A/C for the previous owner. He said it probably is a vacuum leak. I tried to run the A/C and it just blew hot air, awesome!!! After letting it the car run for a few minutes, I shut it off and was going to start it again. but noticed as I turned the key I couldn't hear the vacuum pumps do there thing.......major issue? Or is it just tracking down the leak and simple fix??

[mgbrv8]

If you have to pull the plenum here are the pics of my pull I hope they help

https://www.facebook.com/media/set/?...1&l=8f46fa4533

Dave

[Dynomite]

Originally Posted by rush91

I turned the key I couldn't hear the vacuum pumps do there thing.......major issue? Or is it just tracking down the leak and simple fix??

One vacuum pump under passenger headlight. When you turn the key on (do not start) the vacuum pump should pump for about 3-5 seconds. Then stay off for minutes if you have no leaks. If you have vacuum leaks, the vacuum pump will cycle on and off. If the vacuum pump does cycle off for even a few seconds the secondaries will function normally.

If I understand your situation correctly

It sounds like you have an inoperable vacuum pump.

And you are mixing AC issues (you say you have R134a after the Marc Conversion) with Vacuum issues ....which the two issues have no association

Add some R134a (you might have to jumper the AC low pressure switch during the replenishment of R134a).
If you have adequate AC pressure you will hear and can see the AC compressor Clutch engage. If the AC compressor Clutch does not engage, you most likely have lost AC pressure (the reason you have to jumper the AC low pressure switch during refilling of R134a).

[rush91]

Originally Posted by Dynomite

One vacuum pump under passenger headlight. When you turn the key on (do not start) the vacuum pump should pump for about 3-5 seconds. Then stay off for minutes if you have no leaks. If you have vacuum leaks, the vacuum pump will cycle on and off. If the vacuum pump does cycle off for even a few seconds the secondaries will function normally.

If I understand your situation correctly

It sounds like you have an inoperable vacuum pump.

And you are mixing AC issues (you say you have R134a after the Marc Conversion) with Vacuum issues ....which the two issues have no association

Add some R134a (you might have to jumper the AC pressure switch during the replenishment of R134a).
If you have adequate AC pressure you will hear and can see the AC compressor Clutch engage. If the AC compressor Clutch does not engage, you most likely have lost AC pressure (the reason you have to jumper the AC pressure switch during refilling of R134a).

My bad. You are right I am mixing two issues. I could always hear the pump under the headlight turn on when the ignition would be turned on, but not started. It then would buzz about every 10-15 seconds. Now I hear nothing except the fuel pump....... should I start to see if the vacuum fuse has blown? And would the secondaries be working if the vacuum pump wasn't working? The car seemed to run just fine, the secondaries opened up under throttle.

[Dynomite]

Originally Posted by rush91

My bad. You are right I am mixing two issues. I could always hear the pump under the headlight turn on when the ignition would be turned on, but not started. It then would buzz about every 10-15 seconds. Now I hear nothing except the fuel pump....... should I start to see if the vacuum fuse has blown?

You could start with ignition key on and check for 12 v at the Vacuum Pump. If no 12 volts...then fuse or wiring....if 12 volts...then vacuum pump.
If vacuum pump....pressure sensing circuit or pump circuit.

Originally Posted by WVZR-1

Vacuum pump is a 10AMP IN-LINE fuse over near the grounds etc in the vicinity of the battery on the LH rear wheel-house panel? If you have a FSM it's in the image at 8A-201-8 in book 2.

Is that the same location of the Vacuum Pump Fuse for the 1990?

Thanks for the information......

Originally Posted by MuRCieLaGo

There it is, thanks a lot! It was blown so I changed it. Vacuum pump is now working.

Just inside and to the rear of the Drivers Side Front
Wheel House Panel almost directly below the Brake Cylinders

Originally Posted by MuRCieLaGo

Vacuum pump is now working.
However, it turns on every 2 seconds or so when key is on. Vacuum leak?

Yes...you have a vacuum leak

Finding A Vacuum Leak

[rush91]

Originally Posted by Dynomite

You could start with ignition key on and check for 12 v at the Vacuum Pump. If no 12 volts...then fuse or wiring....if 12 volts...then vacuum pump.
If vacuum pump....pressure sensing circuit or pump circuit.

Thanks Dynomite!! Will try and see..... And on the A/C issue, it just blew hot air back to my face. Marc said the most common location for a refrigerant leak is at the high pressure side service port. Any way to check that, to see if it is leaking?

[Dynomite]

Originally Posted by rush91

Thanks Dynomite!! Will try and see..... And on the A/C issue, it just blew hot air back to my face. Marc said the most common location for a refrigerant leak is at the high pressure side service port. Any way to check that, to see if it is leaking?

You are lucky you have R134a which is a lot cheaper to deal with

Google ac 134a leak detector and you will see all sorts of leak detectors.

I am assuming you have R134a??

[rush91]

Originally Posted by Dynomite

You are lucky you have R134a which is a lot cheaper to deal with

Google ac 134a leak detector and you will see all sorts of leak detectors.

I am assuming you have R134a??

Yes I do, whew! Marc said he converted it over to R134a for previous owner....

[Dynomite]

This is an example of how bad the Vacuum Pump Condition can get Vacuum Pump Issues

[rush91]

Well I disconnected the battery for a minute.....got back in car turn ignition on but didn't start the car. The vacuum pump was loud and working, and the code 09 reset. Can't be THAT easy of fix......rechecking all I can.