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I attended a trackday recently on which the car ran faultlessly until the drive home. I immediately noticed that the car was slightly hesitant and on climbing any hill there was a significant power loss meaning I was unable to maintain my speed let alone accelerate. On the motorway the car will just about reach 70 but there is no more to give and the engine feels as if it is missing albeit very slightly almost imperceptibly and therefore may be me being over sensitive. Pulling out of a junction can be dangerous as the can is likely to bog down and almost stall.

All the fluid levels are fine and the right colour / consistency.

The engine starts and idles as normal it will even rev smoothly from idle.

The exhaust smells normal although it may be slightly louder; although it definitely is not blowing. Although, when I tested to see if it was blowing with a rag over the end I was surprised at how hot the exhaust gases were and that was after a slow drive.

The Magnecor blue HT leads were fitted about 18 months ago.

The car is currently in a garage and they have checked the air flow meter and it is working within acceptable parameters.

Anyone have any ideas?
 

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It sounds like a cambelt timing issue to me. Maybe during trackday it jumped over 1 teeth on a camshaft.

Same symptoms appears with short nose crankshaft once the woodruff key damaged the crankshaft and mess up the timing.
 

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Discussion Starter · #3 ·
It sounds like a cambelt timing issue to me. Maybe during trackday it jumped over 1 teeth on a camshaft.
Same symptoms appears with short nose crankshaft once the woodruff key damaged the crankshaft and mess up the timing.
Thanks I will get them to check however the cam belt and pulleys were replaced last year and within last 1500 miles.
 

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More likely coils. Our Mk2 had an intermittent cold start fault where it didn't have a noticeable misfire but had no power at all. After a while it'd clear up and be normal again, until next time it was cold started. Swapping the coils fixed it.

Daz
 

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Discussion Starter · #5 ·
Update: according to my garage the engine still has a pronounced/noticeable flat spot below 4000rpm i.e. whilst closed loop. The engine revs freely without load but as soon as a load is applied it struggles.

The following has been checked:

Cam timing
Ignition timing
AFM
Coil packs
HT leads
Damaged pipes

The garage is a Bosch garage but of course their diagnostic computers struggle to identify faults with the older ECUs like ours...

Any ideas as the track day season is fast approaching!
 

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Clutch slip ??
 

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Discussion Starter · #7 ·
Clutch slip ??
No new clutch fitted very recently and if it was slipping this would manifest itself as a rise in revs as opposed to a flat spot i.e. A loss of power.
 

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Discussion Starter · #10 ·
We think it may be a partially collapsed cat or exhaust baffle.... What this space...
 

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Discussion Starter · #12 ·
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