Got the '87 XJ6 back from the shop today because the shop can’t figure it out and has reached the end of their rope. We’re a little hamstrung because we lack the tools to completely diagnose the problem and are in the throwing-parts-at-it stage.
This is what has been thrown at it so far:
- One complete, new set of injectors
- Two sets of spark plugs
- Cap & rotor + 2 sets of plug wires
- 2 coolant temp sensors
- 1 airflow meter from Everyday XJ (used)
- Cleaned/reoiled the K&N air filter
EDIT: I also forgot the following has been changed/replaced:
- Cold start solenoid (twice)
- Fuel pressure regulator
The car basically is a brick. It is dumping black smoke out both tailpipes. It builds revs very slowly and is hesitant to rev beyond 3,000 rpm, but will do it. It will not pull a hill of any kind. The in-dash computer, which I’ve found to be quite accurate on these cars, is reading MPG of between 5-12.
We also believe now that the catalytic converter has been ruined from all the raw gas being dumped into it. At the end of a 10-minute drive this afternoon, it began dying at stop signs, and it had trouble going up a 2-foot incline (no exaggeration) into my garage. When it finally got in the garage, I was greeted with a strong smell of unburned fuel and catalytic converter.
I have no shop around here that has Jaguar diagnostic tools from a S3 car, so we’re stuck in that regard. The shop wants me to get another airflow meter, or maybe a new computer. Something is causing the car to dump raw gas, wide open at all times. The car actually runs BETTER if you disconnect three of the fuel injectors.
As simple as these cars are, there doesn’t seem to be a lot of components involved in this problem. It would seem to me it’s either a computer issue, airflow meter issue or there’s compromised wiring somewhere. I’m open to suggestions here but as you can see from the list above, we’ve already thrown quite a bit at it.