hi all 2002 x308 I am having a problem with getting my car passed for inspection the onboard monitors will not reset I have driven the car for 250 miles and no good, still the same 3 monitors will not clear the garage told me to keep on driving is there a problem with the computer. this is driving me nuts.... any thoughts would be appreciated

 

You have not described enough of what has and has not been checked for anyone to agree or disagree! I will say that computer failure is not the first suspect when readiness check will not pass! Any stored codes? What are the fuel trims doing? What codes were there befoire they reset them---
If it was once working, then the monitors fail, it is almost assured a code came up between the events.

 

hi sparkenzap there are no codes the last thing I did with this car, was to change the valley hoses where I had to take off the intake manifold. that was 6 months ago. there has been no codes or any other problems since. the onboard monitors fails on CCM CAT EVAP so I am at a loss as what to do next. I now have driven 450 miles and still no reset any idea's would be appreciated thanks jrb53

 

I hope motorcarman or someone who REALLY knows what they are talking about stops by, but until then I offer my analysis based on limited expertise;

You have three problems; the EVAP system, the Comprehensive Component Monitor (which is generaly transmission related, and the EVAP vapor pressure test. The three would seem to be unrelated, so it MIGHT be possible that your mechanic is right and the computer is to blame.
However, changing the ECU is not an inexpensive fix, so I would try to get the go after the three issues. First, I would do a "hard boot". (Remove the battery lead for a few seconds. Then I would so a reset with an OBD scanner (that comes from a Jag document concerning CCM), then I would assure the tank is between 1/2 and 3/4 full (the easiest way for EVAP). Then run at idle for 10 minutes. Then begin your drive cycle, holding speeds steady for a mile at a time, alternating between 35mph and 45 mph or so for 5 or 8 cycles. No hard accelerations. Then a hard accell or two to 50 mph. The 15 or 20 more "normal" non highway drive miles. Some documents claim you should be careful to avoid sloshing the gas in the tank so the EVAP has easiest effort.

If you still have all three after that, I would get it on a WDS or IDS system before I changed the ECU. If one or more completes, I would then begin serious diagnosis of the remaining tests.

Good luck!

 

I forgot to mention- Using your scanner, make sure the engine coolant temperature sensor is measuring 185F or more before the cycles begin.

 

I had a similar problem on my 2002 XJR. A tech at the dealer said it was almost always the purge valve. I went ahead and bought one and the codes cleared up at about 90 miles.