97 Chevy Suburban: 4wd..idling..the brake pedal, the engine..rough

97 Chevy Suburban: 4wd..idling..the brake pedal, the engine..rough

My parents have a 97 Chevy Suburban 4wd. The brakes are hard to push down on and require more pressure to stop the vehicle. Also, while idling and pressing the brake pedal, the engine runs very rough. I'm thinking that it is a vacuum leak of some sort. Could it be? Are there any simple test that I can do to narrow down the problem? Is there a check valve or some other thing that is common for a Suburban that can be replaced simply? Or could it be the master cylinder? Any help would be great. Thanks.


Check the link below for Answer:

http://www.justanswer.com/chevy/2ivnt-parents-97-chevy-suburban-4wd-brakes-hard.html

the brake pedal, the engine..rough

Vacuum Booster

REMOVAL & INSTALLATION:

REMOVAL & INSTALLATION

See Figure 1

1. Disconnect the negative battery cable.
2. Apply the parking brake.
3. Unplug all necessary electrical connections.
4. Remove the master cylinder from the booster and pull it off the studs, CAREFULLY! It is not necessary to disconnect the brake lines.
5. Disconnect the vacuum hose from the check valve.
6. If necessary, remove the brake light switch.
7. Disconnect the booster pushrod at the brake pedal.
8. Remove the booster mounting nuts, located on the inside of the firewall.

 

Fig. Fig. 1: Vacuum booster mounting

1. Lift off the booster and remove the gasket.

To install:

1. Install the booster with a new gasket.
2. Tighten the booster mounting nuts to 21 ft. lbs. (29 Nm) on all except 1996-98 models. On 1996-98 models, tighten the nuts to 26 ft. lbs. (36 Nm).
3. Install all remaining components.

http://www.au tozone.com/autozone/catalog/parts/partsShelf.jsp?categoryDisplayName=Brakes+%26+Traction+Control&fromType=parts&fromString=search&parentId=44-0¤tPage=1&filterByKeyWord=brake+booster&isSearchByPartNumber=false&navValue=14400143&categoryNValue=14499999&fromWhere=&itemId=143-0&displayName=Brake+Power+Booster&searchText=brake+booster

Brake Power Booster

Showing 1 - 2 of 2 Items
Sort by Price:  High  Low --- Select a Brand --- Cardone Reman Cardone Reman / Brake Power Booster Part Number:
54-71085   Price: $125.99
Core*Core value is the used part that manufacturers use for rebuilding. AutoZone charges the core value to customers because manufacturers include it in their prices. When you return your core to AutoZone, we'll refund your core charge.: $28.00
Total: $153.99 Application:
With JB5, JB6 and JB7 brake system
Warranty:
LLT Notes: W/o master cylinder
STORE PICK UP IN STOCK SHIP TO HOME AVAILABLE  Cardone Reman / Brake Power Booster Part Number:
52-7358   Price: $176.99
Core*Core value is the used part that manufacturers use for rebuilding. AutoZone charges the core value to customers because manufacturers include it in their prices. When you return your core to AutoZone, we'll refund your core charge.: $46.00
Total: $222.99 Application:
With JB8 brake system
Warranty: