I have a 2000 Jaguar S Type 3.0L that has been having performance problems for the last 8 months. I have had the following service done: replaced the head gasket cover, coils, belt tensioner and pulleys, fixed a leak at the intake manifold, replaced the inlet manifold, replaced the egr valve, replaced hoses and gaskets, replaced the water pump and serpentine belt. Unfortunately we continue to have problems or encounter new problems after service.

Currently the car has a loss of power and a loss of pressure. It has a rough idle and during acceleration and higher speeds drives very rough.

We have spent $4,000.00 in the last year on this car without success.

Anyone have any ideas???

I have a CD Technical Service Manual (Jaguar Technician Information System) with instructions for repair and service but it seems the issue could one of several problems. I was told that a computer diagnosis will not show the exact problem so if anyone has had a similar problem I'd truly appreciate some assistance.

 

Since you've done all that work, look at the wire loom near where the fuel line connects to the fuel rail. That's top dead center at the back of the engine. Mine chaffed there and gave me intermittent problems.

 

Has the car thrown any codes? Places like Autozone and Advanced Auto Parts will read them for you at no charge....

Your car may have multiple problems. Vacuum leaks are common, particularly in a car as old as yours. You may also want to do some research on fuel injector cleaning....

 

Ouch!
It MAY not show the EXACT problem but.... $4000 in.... it sure sounds worth a try!

I'd spend no more $$$ until I'd got my own OBD tool (an elm327 is about $20 on ebay) and spent time with it.

The reason to get the tool is that you can do lots more than just read codes. You could do with lots more.

 

trauch, though we should avoid the "Sounds" like this is the problem mentality...it sure does "sound" like there is either spark leaking from the wires/coils as suggested by jagtastic, or head valve leakage? You mentioned "losing pressure", where you suggesting loss in compression? I hope you find much simpler and way less costly spark leakage.

 

jagv8: I think that's great advice. I have taken it to Advanced Auto Parts to get a diagnostic but I think a $20 investment in an ELM327 is a smart move. I have just ordered one on EBay.

How does the reading from the ELM327 tools compare to the what you'd get from the Jaguar dealer?

 

The jag tool (IDS) needs someone who can use it for diagnosis. Great, if you know you have that someone. It also takes time to go through all the readings. Again, great if you can afford to pay for that.

No question: a competent jag tech is the ideal. Looking at your list of parts etc, it doesn't look like you've had such a tech (whether with or without IDS).

IDS does all the modules. The elm only does the generic things, in practice from just the PCM. But you appear to have a problem with the engine so the other modules are likely irrelevant (for your issues).

IDS also does all the sensors, whether for engine control or not. You don't care right now about the non-engine ones.

That does leave some (few) engine ones that are not generic, sadly. (As I understand the car laws, the maker must document them and provide the doc if you ask. Few makers really do that properly, but hey mostly doesn't matter.)

If you want a far better tool than the elm, get AutoEnginuity. It does the extra sensors and the other modules. It's about $450.

I have both elm & AE. No question: AE is far better. But it costs lots more. You likely don't need it for your problem.

bfsgross asked about the losing pressure - c'mon tell us! (E.g. if it's a compression problem, an OBD tool isn't what you need.)