Hello All,

I'm looking at replacing my fuel pressure regulator because I'm getting codes for both banks being 'Too Rich'. I've cleaned the injectors, I've replaced the fuel pump and fuel filter. I have a new MAF sensor and air filter as well.

I'm thinking that the pictures below from my 1998 Vanden Plas showcase the fuel pressure regulator but I'm not 100% sure.

I've undone the two bolts that hold it in and one bolt on the bracket that goes to the intake manifold. I've also taken off the vacuum line as you can see.






I went ahead and ordered a new fuel pressure regulator off of Rock Auto but it does not look anything like my current one.


Did I buy the right part here? If so, how exactly does this bolt in lol. I saw other threads which made this replacement make sense.

Thank you all for taking the time to review this.

Sincerely,

Jake

 

What you got from Rock Auto is NNE5203BA which is for VIN 853936 and later. You need pressure regulator NCA5203EA which comes together with the pipe NCA3007CA as a complete assembly and it is for VINs up to 853935:

SNG Barratt show it as NLA but you can google for it (for NCA5203EA) and see if any other Jag parts supplier still has it, otherwise look for used one on Ebay. Examples:

https://www.jagbits.com/product/NCA3007CA.html

https://www.ebay.co.uk/itm/FUEL-RETU...-/273053655636

Rock Auto provide wrong info for the regulator you got saying that it is alternative for NCA3007CA & NCA5203EA but it is not so you should return it for a refund.

 

Wow thank you so much for the detailed reply.

You're a legend!

I will follow-up with Rock Auto to ensure others don't make the same mistake. I'll get them to edit their listing.

Sincerely.

Jake

 

Hi just looking to follow this up as I have the same regualtor in my Jag. Did you change it and did that sort out your problem or what ?

 

The problem was the regulator without a doubt.

It was seized which caused the fuel rail pressure to be 110 PSI instead of the stock values.

This caused the injectors to drip due to too much fuel on both banks, ending up in rich codes.

I sourced several fuel pressure regulators to replace it that were used and kept swapping them until one worked.

Sincerely,

Jake

 

A bit of an old thread but going through the same exact thing so I wanted to follow up. When replace the part did you have to remove the entire throttle body assembly and replace that gasket as a result or were you able to slip the regulator out of the hose and just replace the regulator itself? It seems really tucked away and I'm having a hard time spotting the bracket it's mounted by underneath the throttle body. Thanks!

 

This is a great example about how Jaguar determines which part fits your car. The last 6 digits of your VIN should always be provided when ordering parts. Jaguar makes running changes so even though the car looks the same over time there are significant differences as shown above.
.
.
.

 

So. Once those crusty things are all used up, time to junk my XJR? I pulled the vacuum line off mine and no gas there, but it seems like a leading candidate for P0172. Mine looks better than the used ones on ebay. Wonder if anybody rebuilds them or ??