v6 unwilling to rev ?

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Gripped
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v6 unwilling to rev ?

Post by Gripped » Fri May 24, 2019 5:34 pm

Hi

Our V6 is as smooth as Castrol, and has had new HT leads, new dizzy cap/rotor, new sparks. It sounds spot on, with no mis-fires etc.

It is fairly lively and eager to pull away from a stand still, plus it will happily do 70+ mph. BUT, it doesn't seem to like to rev beyond 3,000 - 4,000 rpm much. Even if you force it to kick down, or put it in S2, it doesn't seem that keen on revving. Reading on here, the V6 makes its power higher up the rev range, so I was interested to see what performance it had, but I've been a bit disappointed with it so far.

I'm used to my Italian engines, which come alive at around 4,500rpm, so I was hoping for something similar albeit, less exciting !

Any ideas? Blocked fuel / air filter maybe ? (although the air filter looks pretty clean)

Welcome your thoughts.
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Re: v6 unwilling to rev ?

Post by g8dhe » Fri May 24, 2019 10:07 pm

There is this diagram, little hard to read but it will give you a clue viewtopic.php?p=645634#p645634
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Re: v6 unwilling to rev ?

Post by Gripped » Sat May 25, 2019 12:19 am

Thanks

I'm not sure what that shows?

My query was that previous threads have noted that the V6 makes power at the top end, but ours seems unwilling to rev to the top end.
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Re: v6 unwilling to rev ?

Post by g8dhe » Sat May 25, 2019 8:16 am

It shows Power and Torque against RPM. Hence you can see where the peaks are in relation to RPM and each other.
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Re: v6 unwilling to rev ?

Post by Gripped » Sat May 25, 2019 10:46 am

Thanks for that.

Yep, it shows the torque and bhp dyno curves. Peak bhp showing at around 6,000rpm etc.

But my query is about the engine being unwilling to rev into the higher range and what the solution(s) might be.

I'm thinking possibly fuel filter, throttle cable slack, ??

Grateful for any pointers
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Re: v6 unwilling to rev ?

Post by Doone » Sun May 26, 2019 8:15 pm

But my query is about the engine being unwilling to rev into the higher range and what the solution(s) might be.

I'm thinking possibly fuel filter, throttle cable slack, ??

Grateful for any pointers
Try the filters, cable and fuel cap breather first. :)

The timing belt can jump a tooth, which can cause the symptoms you describe. But it's rare so it's not very likely to be that. But I thought it was worth mentioning in case you can't find a different cause. :)
Allan's closed. We recommend PGS (Plymouth Garage Services) or Mayflower Auto Services in Plymouth.
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Re: v6 unwilling to rev ?

Post by Gripped » Mon May 27, 2019 10:46 am

Thanks for that.

I've tightened the throttle cable which was quite slack, and this has helped. She runs very well, so I'm fairly convinced that there is nothing mechanically wrong. I'll try a bit more tinkering.

8)
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Re: v6 unwilling to rev ?

Post by rita » Mon May 27, 2019 2:57 pm

Gripped wrote: Mon May 27, 2019 10:46 am Thanks for that.

I've tightened the throttle cable which was quite slack, and this has helped. She runs very well, so I'm fairly convinced that there is nothing mechanically wrong. I'll try a bit more tinkering.

8)



Have you changed the fuel filter and checked the fuel cap breather, but more likely to be filters 2off
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Re: v6 unwilling to rev ?

Post by Gripped » Mon May 27, 2019 3:10 pm

Thanks - I think those will be next on the list !

Cheers
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