I have been having starting issues. It happens when cold or hot. the starter just cranks and cranks for a while. Other times it starts right up. Its one of those difficult random problems to solve, though stepping on the gas seems to help it along when its struggling so I'm leaning towards it being a fuel issue. I checked the regulator by looking for a leak with the engine running and it seems fine. Anyway, I was looking for a fuel pressure gauge to install as away to troubleshoot and I came across a sweet deal for a new Bosch fuel pump $80 with shipping, from Amazon (Amazon.com: Bosch 69506 Original Equipment Replacement Electric Fuel Pump: Automotive). Cant believe what this guy is asking $312 for the same pump
: http://cgi.ebay.com/ebaymotors/Bosch...ht_1001wt_1167

At 112k, it will be nice to know that i am driving with a new fuel pump. I have been stranded in the past because of old fuel pumps over 100k, mostly in college when I would often run out of gas. Who knows what this 20 year old car has been through, , so Im replacing it along with the pump filter. I already replaced the filter up front.

I looked into getting at the fuel pump and it seems I have to pull the bracket off in the trunk, remove the convertible top pump, relays, etc. seems fairly straight forward. I think I can have it out in an hour if I move fast, just seems like a lot of ratcheting.

Anyway, to get to my intended question, since Im going through all this work should I also clean the tank, or is that wasting my time?

What process should I use if I decide to clean the tank. I have read muriatic acid works well. I am more a fan of avoiding purchasing products made for tank cleaning. Often they are just marked up nicely packaged cheap readily available chemicals. Muriatic acid is about $5 a gallon. Has anyone tried this process?

 

Hello, I had fuel issues with my 96 XJS 4.0 2+2. I was able to replace the fuel filter without totally removing the tank. All you have to do is move it forward enough to get your hand down through the top to remove the old filter and replace it with the new one. By the way, my fuel issues were due to a non-operating return valve in the tank. Few tech's new what was going on. I was getting a buzz sound out of the tank and couldn't figure it out. Traced the gas lines, check and changed the fuel filter, etc. Nothing helped. So, I isolated the return line via a plastic hose from the gas line in under the hood to the gas tank. No sound. So, I removed the tank and looked inside using a mirror. Sure enough, there was a metal return valve before the fuel pump. I got a long knife and cut the rubber hose before the valve. Vola, the noise is gone, new fuel pump, and didn't have to remove the tank. Check your fuel filter for particles. I cut my fuel filter in half and looked inside. It was dirty but no particles. So, I assumed the tank is ok. I wouldn't remove the tank unless it's absolutely necessary. Good luck.

 

Just curious as to how long it actually took you to replace your fuel pump. I sat out to do my about 6 wks ago and doing so in my spare time. A very long project that I hope i don't have to get into anytime soon again.

Tony

 

Hi Hoodun

Replacing the Fuel Pump on an XJS 4.0 Convertible is the Job from Hell, especially when you try and get those awkward to get to pipes off.

As for Cleaning the inside of the Tank (if you want to/need to) I have heard Apple Cider Vinegar works well.

And probably much cheaper than Muratic Acid.