QuestionQUESTION: I bought an '84 XJ6 7/24/10 as a project, I've been reading a lot here since, but haven't seen this one yet - the seller pointed out a new fuel pump and filter in the trunk, but I find it odd that when the car is running, I can hear the pump running from the driver's seat, or from outside the closed trunk if I walk around the car. Is this at all normal? Mine is also doing the cold start stall thing, etc, and I plan to replace the coolant temp sensor this weekend, and I am also working to replace all vacuum lines, but I can't believe it is normal for the pump to be so loud. Ideas?
ANSWER: Hi Michael,
Even though it is normal to be able to listen carefully and hear the pump running it is not normal for it to be noticeable if you were not trying to listen for it. Open the trunk and remove the spare tire and look at the pump and the mounting of the pump. It should be mounted in rubber and no part of the pump in contact hard to the body.
If all that looks good you may have a pump wearing out as the Bosch injection pumps do tend to make a lot of noise when they ware out.
Howard
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QUESTION: Howard,
Thanks for taking a moment to answer my question. The pump and filter do actually appear to be quite new, and the pump is mounted in a rubber coated bracket. With the noise - a constant "whirring, buzzing", you can feel the hoses attached to it vibrating. Is there any other known cause for this?
Michael
AnswerThe fine vibration is normal for the design of the pump. It is a roller cell pump and the pressure from each roller as the pump turns causes a fine vibration. I can't give you any figure on what is the normal sound and what is louder than normal so your best bet is to locate a Jaguar specialist in your area to listen to it or find other Series III cars to listen to.
Howard
