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Insufficient Vacuum -p1476

Old 12-26-2008, 03:59 PM
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Default Insufficient Vacuum -p1476

1 Fault Found: 17884 - EVAP Leak Detection Pump: Insufficient Vacuum P1476 - 35-00 - -

Can anyone help with the above? I recently changed my o2 sensor ( B1 S2 ) then a day later this code comes up.

Does this mean the actual LDP is bad? I've seen other codes come up as very small leak which im hoping isnt my case. If i had a leak wouldnt I get a different code vs Insufficient Vacuum?

IF not, where should I be looking to isolate this? Would it more along the lines of a small leak in a hose from the LDP to the front of the car?

thanks for the help

99 30v
Old 12-27-2008, 10:35 AM
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Usually, if you have a leak, you'll see a code for a leak. P1476 is pointing directly at a bad LDP. The ironic thing here is that LDPs don't pull vacuum, they actually pressurize the system. The longer the run cycle beyond a set point, the larger the leak. There is a fliter inlet on the LDP, it's worth taking a look at for a clog. Additionally, check the wires and connector to the LDP for corrosion.

Or, erase the DTC and perform a short test to see if it comes back.
Old 01-27-2009, 02:59 PM
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based on the error code: 17884 - Insufficient Vacuum, I pretty much thought I had a leak in a hose or something. What drove me nuts is where is this pump getting vacuum from. So after weeks of searching and reading, basically it receives vacuum from intake manifold.
So this weekend I put the car on a lift. Inspected the lines under the car, by the gas tank, and behind engine. Still couldnt find a problem.
So, I removed my intake and plugged in a smoke detector and still no leak in the lines.
What I did discover, although Im aware of a broken vacuum hose is that smoke started to come out of that hose. Im thinking to myself, WTF is this hose.

So after gazing into my new bentley book, that hose is part of the "check valve" thats ontop of the back of the engine. One hose goes to some valve thats on the front of Bank 1. The other apparently goes to some vacuum reservoir thats in the front Right wheel liner? ( anyone know what that reservoir looks like? )

Since smoke was coming out of that hose during my troubleshooting, im suspecting thats why im getting that insufficient vacuum code. Odd but, am wondering if that could be the culprit.

Does anyone think or suspect that this hose would trigger that CEL for my EVAP?

ohh btw,...does a burning clutch smell like a dead mouse? Long story short, since my car is lowered I needed to put the front of some wooden blocks to get the lift under. while giving gas, the garage started to smell like something died in my engine.
I already found a friggin mouse in my engine ( dead of course ) just hope I dont have another one. Plus, the smell is around the front right wheel liner which I hope they didnt use to build a nest. they probably nibbled on some of the hoses so that I have to check.
Old 01-27-2009, 05:24 PM
Join Date: Mar 2008
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I would pull that wheel liner and make sure there is not a nest there. Just to make sure there is no critters in there.
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