I have a 2018 F Type that recently developed a misfire . RAC at roadside diagnosed either injector problem or coil pack . Car was recovered to a Jaguar main dealer who did initial diagnostic tests ( cost over £300 ) but then said they couldn't identify the problem and that they needed to do engine compression tests ( further £477 ) . Having done the compression tests they told me that the problem was a faulty injector ! So i'm looking for advice really as i cannot understand why , allegedly , they couldn't trace the problem in the first round of diagnostics especially as i had informed them of what RAC had said . Why would they need to do engine compression tests to identify an injector issue ? Basically i have a feeling that i am being ripped off ! So is there anyone out there who knows more than i do that could give me more technical view on whether what has happened is fair or not ? Help gratefully received , thanks Geoff
effectiveness of main dealer diagnostic tests
- Thread starter geoffw
- Start date
WShudds
New member
1) You are being ripped off in the sense that £300 to scan the ECU is shameless extortion. Ask for a list of error codes they they found and compare it to RACs report.
2) You need to get your own code reader or find someone who does who could give you a hand so you can see for yourself what codes the ECU is reporting. From there, a quick search online will tell you what could be wrong. I got this one and it works really well. It will save you a lot of hassle going forward. MrGB (F-type owner) did a review on YouTube and shows how it works
Deal: OBD2 Code Reader TOPDON ArtiDiag500, DIagnostic Scanner Engine/Transmission/ABS/Airbag Car Diagnostic Tool, 5 Reset Functions for Oil/BMS/ABS/ETS/Throttle, One-Click Lifetime Wi-Fi Update https://amzn.eu/d/eZzlJw4
3) £400 for a compression test is not that much more than the average and better than going straight to replacing the injector as misfires could be rooted on faulty/stuck inlet valves, blown gasket, blown cylinder head O'ring. So it's good news that's passing. Ask for a report showing the compression result and post it here for comparison/advice.
4) when where the spark plugs replaced last?
If you could post here the error codes found by RAC and the dealer, we should be able to to give you further advice which may include running a bottle of 44BK, HHO carbon cleaning, etc before moving to replacing the injector.
2) You need to get your own code reader or find someone who does who could give you a hand so you can see for yourself what codes the ECU is reporting. From there, a quick search online will tell you what could be wrong. I got this one and it works really well. It will save you a lot of hassle going forward. MrGB (F-type owner) did a review on YouTube and shows how it works
Deal: OBD2 Code Reader TOPDON ArtiDiag500, DIagnostic Scanner Engine/Transmission/ABS/Airbag Car Diagnostic Tool, 5 Reset Functions for Oil/BMS/ABS/ETS/Throttle, One-Click Lifetime Wi-Fi Update https://amzn.eu/d/eZzlJw4
3) £400 for a compression test is not that much more than the average and better than going straight to replacing the injector as misfires could be rooted on faulty/stuck inlet valves, blown gasket, blown cylinder head O'ring. So it's good news that's passing. Ask for a report showing the compression result and post it here for comparison/advice.
4) when where the spark plugs replaced last?
If you could post here the error codes found by RAC and the dealer, we should be able to to give you further advice which may include running a bottle of 44BK, HHO carbon cleaning, etc before moving to replacing the injector.
scm
New member
For a 2018 car, you'd be better off finding a decent independent whom you can trust, rather than a main dealer who will probably prefer to replace components at the customer's expense than do proper diagnosis. Give us a clue of your approximate location and maybe a member on here can recommend someone.