Slightly Worrying

I'm not familiar with Jeeps but it seems the air is leaking into what should be a vacuum area. This could be simply via a perished or split pipe from the inlet manifold, or more seriously, through a hole in the diaphragm if it's perished. Can you not locate the noise accurately using a stethoscope?

Rob Graham

Or if it only occurrs when you press the pedal, it's the normal operation of the servo.

Sure. I rather assumed that the noises the OP mentioned were new ones.

Rob

First check was the servo hose to the inlet. It's fine. And if you listen down by the brake pedal with the engine running, you can clearly hear air being sucked in past the pushrod into the servo - And therefore out into the engine. My guess was hole in diaphragm as I couldn't for the life of me think how else the air would be being sucked through from inside the car! But it's always nice to get a second opinion :)

Trouble is, the owner keeps saying "It stops fine, there's nothing to worry about". Correct me if I'm wrong, but if the diaphragm has started to give up, albeit very slighty so far, it isn't exactly going to get better all by itself, is it? I'm kind of scared there'll be a woman driving a 2 ton brakeless heap of metal on the roads! ;)

That's what I thought when it was first described to me, but the owner swears blind it's a new noise... The problem isn't so much the noise (which is a little loud for a servo, louder than it used to be on that car, but still "normal" in terms of what it sounds like) but the fact the servo is sucking air from inside the car, into the engine.

I'd love to know why this "car" (bloody agricultural never taken off road thirsty gutless bad handling shiny red thing) seems to be aging so quickly - Steering damper just replaced, pinion seals shot, and now the servo. It's not like it's that old, or had that many miles on it. There's even rust appe aring on the chassis, but it does look like they only put one thin coat of paint on it in the factory, which might explain that. At 5 years old, I wouldn't want rust on the uderside of a car I'd never off-roaded. Or a shot servo.

Oh, and as an afterthought - Power steering pumps. Is it normal for them to audibly click/ chatter with the engine at tickover? My guess would be no, but I've only had one car with power steering, and that was a long time ago. Seems the thing made that noise when it was bought, but the salesman said "It's perfectly normal for Jeeps to sound like that". Could be true, I know nothing (but more now than I ever wanted to) about Jeeps, but seems a bit fishy to me...

I'm sure there was a Chrysler Jeep TSB concerning the noisy power steering - something to do with the pipes oscillating.

If you hear air being sucked into the servo when the brake pedal is held 'steady' (as opposed to a brief hiss on first pressing or releasing the pedal) then the servo diaphragm is split. On a vehicle like this you *need* the servo - Jeep brakes are not great at the best of times. I think it will be a dealer only part and not cheap.

Chrylser vehicles are not very well made - build quality is behind Euro and Japanese vehicles, that's why it is wearing out so quickly.

Well, it's been like it for at least the last 3 years, according to the owner. Or should I say, it's proably been like that for that long, because yesterday was the first time she'd heard it with the bonnet open...

Can hear a dull sucking noise (as opposed to a sharp one like when pressing the pedal) all the time the engine's running. Ther normal servo noise is also quite a bit louder than it used to be. As in, the owner never heard the servo before, and now it's very very noticeable. However, there is certainly a vacuum in the servo, as popping the hose off with the engine stopped causes a very loud sucking of air, so for the moment at least, the servo is working, although I doubt at full capacity..

Not my problem, thankfully :) But would be nice to find them the same part without the dealer mark up. Even though they do "get family discount". Try explaining that a possbile 10% discount on a 50% overpriced part isn't any cheaper than buying it from a factors that sells it for the sensible price in the first place.

It's not my car, and the owner is very proud of it, if incredibly mecahnically illiterate, so it's very hard to explain anything to her about faults, reasons, etc. I did try asking when the last time she'd heard anyone praise American build quality was, and the only answer she could come up with was Jeep supply the American military. I wouldn't care, but I'm trying to save them time and money, and it's very difficult to argue with that logic, let alone actually manage to explain what's wrong in the first place!

Even so, how can a 5 year old or less car be so bloody tired, no matter how badly made? That might be a rhetorical question, depending on yourt point of view though :)