S Type 2.5 SE - Loss of power, why?

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Sun 19 Apr 2015 14:50
S Type 2.5 SE - Loss of power, why? - bojag.sjr
I had a diagnostic test on my S Type and was told it had quite a few things that had to be repaired. It all started with a loss of power when driving up hill. I'm told I need two new cats, four Lambdas new plugs and ignition coils, all a result of engine backfire. I bought all the parts, only to be told that it could just be air loss from one of the many pipes attached to the engine. If all these parts need to be replaced, would the engine still run, and would the tick over be erratic? I ask because it starts first time, idles well and is not frowning out lots of fumes from the exhaust. If you have any ideas, please let me know.

Bojag.sjr.
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Sun 19 Apr 2015 21:10
S Type 2.5 SE - Loss of power, why? - Wolfan
I had a diagnostic test on my S Type and was told it had quite a few things that had to be repaired. It all started with a loss of power when driving up hill. I'm told I need two new cats, four Lambdas new plugs and ignition coils, all a result of engine backfire. I bought all the parts, only to be told that it could just be air loss from one of the many pipes attached to the engine. If all these parts need to be replaced, would the engine still run, and would the tick over be erratic? I ask because it starts first time, idles well and is not frowning out lots of fumes from the exhaust. If you have any ideas, please let me know. Bojag.sjr.

Get an indy to check it out, mich cheaper than a main dealer and he will want to keap you as a regular.

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Sun 19 Apr 2015 21:37
S Type 2.5 SE - Loss of power, why? - elekie&a/c doctor

Loss of power could be caused by the failure of one or more of the 6 coils.Why does it need all the other parts?Fractured or broken air breather/vacuum pipes are common on these but usually cause a poor idle often with surging.

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Mon 20 Apr 2015 14:11
S Type 2.5 SE - Loss of power, why? - slkfanboy

The plug are a common issue as they are hard/expensive to replace and cause miss fires and poor pulling. Replacing all the coils is a clear sign of bad diagonise. Normal a plug change and test each coil pack.

Air leaks can be detected quite easly with basic diagnostic equipment by a compitent person and would not be confused with a plug/coil pack issue.

I had a 2.5 s-type and I would get the plug changed and the coil packs tested first, mostly to solve your issues

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Thu 23 Apr 2015 15:15
S Type 2.5 SE - Loss of power, why? - bojag.sjr

Thanks for everyones feed back. I had another diagnostic on the car today. The good news is that the cats, lambdas and ignition coils are all okay and that it would benefit from a plug change. However, the mechanic took it on a short drive and then suggested that it could also be fuel starvation. He is now going to run this by a Jag mechanic for another second opinion so, a problem still remains.

bojag.sjr

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Fri 24 Apr 2015 22:51
S Type 2.5 SE - Loss of power, why? - bojag.sjr
Me again. The mechanic that has been trying to find the problems with my car, has run a second diagnostic. Apparently, the first one he did was incomplete. It passed the cats etc, has being okay but wouldn't go any further. Hence the reason for him not finding the fault. Also, the jag mechanic didn't get back to him. This leaves us both in limbo. Anyone know how to clear the code that is preventing further diagnostics, as the second test was the same?

bojag.sjr
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