I have a 2003 jaguar s type 3.0 v6 with a stumbling problem when warmed up.
Running lean, eating my gas rapidly and codes showing p0037,p1647 o2's but something is causing those codes.
Valve covers were done and p0302 coil (cylinder 2) replaced; all plugs good
map & maf sensor replaced, pvc valve also. Battery good.
Throttlebody good.
Have been to three different mechanics; all could not fix problem.
One mechanic says possibly ecu (engine) because he said no voltage to o2's
other mechanic says ecu is communicating and good.
So i am up for suggestions before i get rid of this troubled car?

 

I've moved your question from General Tech Help to S-Type forum. This is the place to post technical questions about your model.

Graham

 

Shall I drive to Florida and slap this mechanic around? Please see your wiring diagrams here, scroll to figure 03.1 for the O2 sensors:

http://www.jagrepair.com/images/Elec...al%20Guide.pdf


Follow the power supply for all four sensors, and this will lead you to figure 01.7. All power goes through relay R2 in the front power distribution box under the hood. Also check fuses F20 and F35 while you're there.

The easiest way to check for a bad relay is to swap R2 with another relay of the same size. Make sure that circuit is working properly and then you have a known-good relay to try at the R2 position.

 

thank you,
I will try that and let you know.
joe

 

I appreciate your response can you direct me where to purchase that relay to have extra just in case all of them I see a used online and they're yellow I don't know the interchangeable number because I cannot locate that either online
Also I know that the Lincoln LS is the twin of my car maybe the parts are generally the same right? On the relays
I am coming up with RY116 STANDARD THAT IS A 40 AMP RELAY WITH SAME PIN LAYOUT AND FITS LINCOLN LS SAME ENGINE AS MINE.
WHAT DO YOU THINK?

 

The easiest method is to search by the Jaguar number on the old relay. Search results will typically include cross references to aftermarket brands. Can't tell you if RY116 will work without the original Jaguar number, but it sounds like you're hot on the trail.

Jaguar was never in the relay manufacturing business. The designers simply picked some industry standard relays for the various applications. The relay manufacturer stamped a Jaguar part number on the same relay that was also sold to Ford, Mazda, Hyundai, etc.

The only downside for us is Jaguar must have specified some very expensive ink for stamping their part numbers. Based on the price for a replacement relay through official Jaguar parts channels, that ink was made from unicorn tears. At least with accurate cross reference info, we can get that exact same relay but at a much more reasonable cost.

When you shop for universal parts like this, make sure you stick to reputable brand names such as Bosch, Standard, etc. Because these are such universal parts, applicable to many vehicles, there is a lot of crap aftermarket stuff out there. Stay away from no-name Chinese stuff on eBay. Same for brands you've never heard of, such as Fling Dung or Wok Hoam. The jury is still out on store brands from discount auto part chains, such as Duralast from Autozone, but personally I avoid them. Myself, I'm very partial to NAPA Premium. Never had a problem with them.

 

Thanks for all your help I appreciate it

 

thank you for all your advice; but with new R2 (relay) and fuses all good, still the same problem.
I will try to find a jaguar expert without the jaguar price locally.
thanks again,
joe

 

Problem solved!
My Jaguar S type was running very lean with P0171,P174 & P0140 codes after replacing all O2 sensors for P0037 & P1647 codes.
The problem was a vacuum leak and the culprit was the Plenum (upper intake manifold and lower intake manifold gaskets).
Also an o ring and some other plastic parts in the Plenum were replaced.
Now running fine.
Every time the plenum is taken off, I would recommend from experience, replace the gaskets and check O rings, plastic parts & etc... because if any one of those parts go, you will have a vacuum leak.

 

Nice work, and thank you, thank you, thank you for the update!