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JamesB
04-11-09, 07:13 AM
I've got a 1998 Pathfinder with a VG33E engine and something like 270,000 km on it.

Over the past week, the engine has begun stalling at idle, and diagnosis of the problem revealed that the stalling only happened if I applied more than moderate pressure on the brake pedal with the engine at idle. Some further experimentation has revealed that the engine won't start if the brake pedal is pushed at the time, and the brake system seems to lose vacuum very quickly after the engine stops. I'm guessing that it's a vacuum leak somewhere in the power brake system.

The only thing between the intake manifold and the booster is the hose and a check valve. Apart from checking the easy to access check valve, what should I be looking for to determine if the booster is the problem before I haul it out?

I've never worked on a brake booster, but I'm assuming if the problem is the booster, then it's most likely a damaged diaphragm that's causing the problem.

Zac
04-11-09, 07:22 AM
It sounds like a good diagnosis already! But just to be sure you could put the check valve in backwards and see if it starts and idles fine. Could also be a split in the hose somewhere.

GTSBoy
04-11-09, 09:00 AM
I'm with him ^

dattoman1000
04-11-09, 09:16 AM
Nissans have a tendancy to tear the front seal
Pull the master cylinder forward and inspect the seal
Might be an easy fit

JamesB
04-11-09, 11:06 AM
Nissans have a tendancy to tear the front seal
Pull the master cylinder forward and inspect the seal
Might be an easy fit
Thanks. That's worth looking at.

bigmuz
04-11-09, 10:26 PM
The idle air controller thingo is probably fucked/ clogged as well. At least with that you can fix it for free.

MRMOPARMAN
06-11-09, 11:07 AM
you didnt happen to buy the booster off highoctane245 did you?