Jeep Grand Cherokee - WK2 - Power Steering issue
Discussion
Morning folks, GC owner with a problem.........
My power steering feels dead undertaking stationery manoeuvres. Parking a good example. Al all other times it is fine. It has a steering rack which is non-mechanical. The fluid is pressurised by an electric motor. I had the P/S fluid changed as it was low (no leaks though) and was quite yucky. I suspected it was the original and should have at least been changed once in its 87,000 miles. This has made no difference though. The garage assured me they had the correct vacuum pump equipment to suck out all the old fluid and to pump in fresh. I ain't so sure though as the mechanic I spoke to referred to taking the hose off the rack that is fed from the reservoir.........
Jeep service in this part of South Wales is, let me put this bluntly, pretty crap. There's a garage in Bridgend that can perform a diagnostic on 20 June! Bless 'em. Then it'll charge £140 and hour and they've allocated 2 hours....so £280 just to advise on the issue. I suspect it's one of two things...the electric pump or the rack itself. Both considerably expensive.
I'm no dullard when it comes to spannering cars but I've no experience of an electric/hydraulic P/S system and my car knowledge is focussed on VAG. Routine maintenance on this Jeep is really kid's play in testament to its design...much easier servicing this than the Touareg I had previously. But I'd really appreciate some advice on how I might be able to identify the issue myself before handing over £300 to the main dealer. That £300 can then go towards purchasing whatever component is playing up.
Playing parts darts is an option and trying a new pump. But a risky one at that. I've no warning lights on the dash but I was wondering whether Jeep diagnostic software might help pin the fault down?
Please throw in your ideas. I'll appreciate any advice.
My power steering feels dead undertaking stationery manoeuvres. Parking a good example. Al all other times it is fine. It has a steering rack which is non-mechanical. The fluid is pressurised by an electric motor. I had the P/S fluid changed as it was low (no leaks though) and was quite yucky. I suspected it was the original and should have at least been changed once in its 87,000 miles. This has made no difference though. The garage assured me they had the correct vacuum pump equipment to suck out all the old fluid and to pump in fresh. I ain't so sure though as the mechanic I spoke to referred to taking the hose off the rack that is fed from the reservoir.........
Jeep service in this part of South Wales is, let me put this bluntly, pretty crap. There's a garage in Bridgend that can perform a diagnostic on 20 June! Bless 'em. Then it'll charge £140 and hour and they've allocated 2 hours....so £280 just to advise on the issue. I suspect it's one of two things...the electric pump or the rack itself. Both considerably expensive.
I'm no dullard when it comes to spannering cars but I've no experience of an electric/hydraulic P/S system and my car knowledge is focussed on VAG. Routine maintenance on this Jeep is really kid's play in testament to its design...much easier servicing this than the Touareg I had previously. But I'd really appreciate some advice on how I might be able to identify the issue myself before handing over £300 to the main dealer. That £300 can then go towards purchasing whatever component is playing up.
Playing parts darts is an option and trying a new pump. But a risky one at that. I've no warning lights on the dash but I was wondering whether Jeep diagnostic software might help pin the fault down?
Please throw in your ideas. I'll appreciate any advice.
Given my memories of unassisted steering massively lightening up with even a little vehicle speed, are you sure the power steering pump is working when the car is moving?
I'm also not sure that the arrangement on your Jeep is anything special - perhaps just not very common in these days of all electric systems. For example, my '04 SEAT Ibiza (and Polos at the same time) had an electrically-driven hydraulic power steering pump. Given Jeep's offroad background, I suppose it is possible that it has a steering box, rather than rack and pinion.
I'm also not sure that the arrangement on your Jeep is anything special - perhaps just not very common in these days of all electric systems. For example, my '04 SEAT Ibiza (and Polos at the same time) had an electrically-driven hydraulic power steering pump. Given Jeep's offroad background, I suppose it is possible that it has a steering box, rather than rack and pinion.
Edited by trevalvole on Friday 28th April 10:03
May be its got all gummed up and is only partially working, and as power assistance is most noticeable at low speeds, that's when you notice its absence?
I'm not sure how much diagnostics will tell you, as it may only monitor the electric motor that powers the pump and not tell you, for example, that the pump is not producing the required quantity of pressured fluid.
I'm not sure how much diagnostics will tell you, as it may only monitor the electric motor that powers the pump and not tell you, for example, that the pump is not producing the required quantity of pressured fluid.
Hi,
Worked as a design engineer in a company that made steering gears and pumps a long long time ago.
The Electric power hydraulic system in your car is not very different to a "traditional" hydraulic system. The only difference is that the pump is driven by a electric motor rather than the accessory belt off the engine. This was mainly introduced for efficiency as there will be minimal assistance required at higher speeds and it is quite wasteful to have a pump running off the engine sapping power as well as wearing down the pump vanes. The steering gear itself can be identical to a traditional hydraulic system.
What I would suggest is:
1. Disconnect the electrical connector to the pump. With the engine started, is there any difference in the level of assistance with/without the pump having electrical supply - if no difference, the likely culprit is the pump.
2. With the engine running, ask someone to turn the steering lock to lock and try to see if the pump is running and whether fluid is flowing through the reservoir.
3. Check for seal leakage from the steering gear. If you can, remove the rubber boot from the ends of the steering gear and inspect for presence of any fluid. There should be no fluid in this area. If there is fluid, then the seals are leaking and preventing the system from pressurising, causing loss of assistance.
Worked as a design engineer in a company that made steering gears and pumps a long long time ago.
The Electric power hydraulic system in your car is not very different to a "traditional" hydraulic system. The only difference is that the pump is driven by a electric motor rather than the accessory belt off the engine. This was mainly introduced for efficiency as there will be minimal assistance required at higher speeds and it is quite wasteful to have a pump running off the engine sapping power as well as wearing down the pump vanes. The steering gear itself can be identical to a traditional hydraulic system.
What I would suggest is:
1. Disconnect the electrical connector to the pump. With the engine started, is there any difference in the level of assistance with/without the pump having electrical supply - if no difference, the likely culprit is the pump.
2. With the engine running, ask someone to turn the steering lock to lock and try to see if the pump is running and whether fluid is flowing through the reservoir.
3. Check for seal leakage from the steering gear. If you can, remove the rubber boot from the ends of the steering gear and inspect for presence of any fluid. There should be no fluid in this area. If there is fluid, then the seals are leaking and preventing the system from pressurising, causing loss of assistance.
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