No/Lo Vacuum

[BrentN]

Hi All,
Now that I have my 99 Suburban, my first real issue has arisen...Low Vacuum-No Turbo.
1st Sympton was heavy black smoke while pulling a steep hill.
I checked the vacuum at the line to the Turbo and I am getting 5in @ idle, nothing any greater with any rpm either.
I then checked the vacuum at the pump line going to the Wastegate Solenoid...its the same.

So, I need a vacuum pump. But my first question is this...is my 99 covered by the 100,000 warranty...and if so, would the vacuum pump be covered.

I know about the aftermarket boost controllers, but if indeed I have the 100,000mile warranty (as well as the balance of the 3y/50,000 mile warranty on the Goodwrench Engine that was put in @ 83,000miles, I dont want to create any warranty voiding situations.

If it (the vac pump) isnt covered by warranty,is this a dealer only item or can I get it @ Napa or the likes.

Thanks,
Brent

[Dvldog 8793]

Howdy
I am in the process of putting in a new motor and was thinking about getting rid of the vac pump. It has to suck HP and MPG. My only concern was the continual SES light. Heath wasn't able to tell me if getting rid of the vac system would put my abdII into fault. I think it really is pointless to a have a driven vac system to run one component that can be run by other means. as far as I know, the warrenty does NOT apply to driven components, otherwise GM would be broke buying alternators :D I did all the work on my motor so if I have a problem I can make it stock again for warrenty issues. As of now the Vac pump isstill on my truck but I'm thinkin that is going to change.
Hope this helps!
L8r
Conley

[BrentN]

Yeah,
I was hoping that they would consider the vac pump a critical part of the engine management system and cover it...It is almost 8am on the west coast. I will give my local chevy dealer a call and get the scoop.

In the long run, if I decide to go with a different controller, I would still like to get the basic system working correctly, and I definately dont want a system that pops a code ...I dont like my dash lit up with warning lights as a normal course of daily operation.

I am still hoping that someone will chime in with cost & source info on the pump. Thanks for your input.

[Kennedy]

When M Rinker was here, a side effect showed at least in his case. He cannot start the engine with the AC on or the belt will squeal and the compressor will not start. The engine must be running for the AC to be engaged. May be an isolated instance, but...


I still prefer the vacuum controlled wastegate for it's true active control. There's more than back pressure to take into account when controlling boost, and a spring loaded dump on the exhaust side cannot account for this.

The vacuum pump should be covered under the emissions warranty if you get the right dealer. Otherwise, I offer the pump with a pulley already installed for easy bolt on installation.

[BrentN]

Thanks John,
I am in overall agreement with you. I try to be as much of a purist as makes sense.

GM put a lot of engineering time into developing the hardware and software for this engine. While others rightfully may need to eeek out that very last pound of torque, I want to maintain as much of the all around driveability of the vehicle...That and it is a vehicle that is a day to day family truck and I dont need oddities occuring while my wife is driving...tends to sour most people if lights are popping on and the engine is doing goofy stuff.

I will check out your website. I did put in a call to my local chev dealer, am waiting for a call back. Am I correct in assuming that the 99 truck had a 100k warranty on it? Was there a year component to it as well...2nd owner transferability?

I am all for having Uncle GM foot the repair bill as long as possible.

Thanks for your help.

[Dvldog 8793]

Howdy again....
The pump from my dealer was $180 w/ no pully I would get it from John at least that way you know where the money is going. My truck had the 100k warrenty on the motor. I had some problems convincing them that the turbo was a critical part of the engine. If your truck has a EGR system then I would say you need the vac for that also. My truck only has two vac lines one from the pump and one to the turbo. I agree with you on the wife/anyone-else driving my truck deal. That's the last thing I need is somebody looking atr my truck and telling my wife that it needs to be towed 200miles hopme because they don't what kind belt to put on! :D
L8r
Conley

[BrentN]

I am still waiting on the dealer...Thursday must be a bad day for them!! I may be a bit screwed at getting them to cough up a pump...my truck is a 2500, thus it has no egr...thus no true emissions issue in the sense of the word, however, I agree that without the turbo, then the engine is not producing intended emissions while under load...as evidenced by the black cloud that I spewing from my tailpipe...That will probably be the tactic I take...Is that it is not normal to belch all of that smoke under load.

I will keep you all updated...If I do have to spring for a pump I will get it from John.

[BrentN]

Update: Looks like it did have the 5y/100k warranty. However, its inservice date was 12/31/98...out of warranty...Oh well.

Guess I need to order a pump. I want to verify the vacuum levels again and actually check the line to the wastegate solenoid for integrity first.

The engine was hot when I checked it...Its possible that there is a leak in the line... I need to get under the cover and look.

It sure sounds like the pump has gone south. I have seen other posts where people have had only 5inches of vacuum..I wonder if this is the vacuum level that the pumps usually fail to.

Thanks again, I will update when I have more to report.

[moondoggie]

Good Day!

"I want to verify the vacuum levels again and actually check the line to the wastegate solenoid for integrity first." From your posts, I couldn't determine if you checked vacuum at the vacuum pump or at the vacuum pump port on the Wastegate Actuator Solenoid. I sure wouldn't spring for a pump unless I had FOR SURE checked vacuum at the pump. The plastic lines are notorious for cracking. (I replaced mine with soft copper from the hardware store - I don't think that will crack in my lifetime. ;) )

Blessings!

Brian Johnson, #5044

[BrentN]

Hey Moondogie,

Here is what I checked:
Vacuum @ wastgate diaphragm = 5in
Vacuum @ line from vac pump @ wastgate solenoid Location = 5in

From what I understand, I should be seeing somewhere around 20 at idle. Is this correct?

From this I am inferring that I have a bad pump (or bad line from the pump to the solenoid).
They only thing I havent done yet is pull the cover off and check the entire line from the vacuum pump up to the solenoid for integrity. Of course now I need to wait, as I just drove it home and it is hot in there.

I tried to figure out where the vacuum line comes out of the vac pump at. Any help here would be appreciated as it is a bit hard to see what is going on down there. I need to pull that line so that I can plug the end and see if it holds a vacuum or not.

You say you ran copper tubing. Did you use those rubber connectors like are used with the hard plastic line?

Thanks for your help. Please steer me in the right direction to find the hose connection on pump.
Brent

[Kennedy]

Just for grins, try shooting some WD-40 in the line at the actuator with engine running. This has worked for me to rejuvenate pumps.

If you need the vac harness I haven't offered it independently due to shipping complications etc, but can ship with the pump. They're pretty reasonable at $15....

[BrentN]

Update:
Checked vacuum line (by itself) integrity- holds without a problem.

I then put a hand pump on that line with the line hooked to the engine vac pump. It holds vacuum great.

I released the vacuum on that line, ran the engine...the engine pump maybe generated an an inch. Put a little lubricant in ...came up to 5inches...never moved above that.

I did notice that the actuator moves completely closed @5 inches at idle.

Does it need the full 20 at the high exhaust pressures?

What say the jury on the vacuum pump? I say guilty.