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Discussion Starter · #1 ·
hi everyone

my 3.0 V6 seems to have a problem that only happens if I push the car to red line if i only rev to 4000rpm there is no issue but if i go beyond to 6000 the car will start to chug and miss fire badly and then I straggle to get to 40mph, there are no error lights on the dash that appear at the time but its like its running on one less cylinder. If I pull over turn the car off and then turn back on then its fine again.

To me it seems that something is reading wrong when the car is pushed to full power and then causes it to over fuel or under fuel causing it to misfire but not sure, I would appreciate any help to diagnose this.
 

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hi everyone

my 3.0 V6 seems to have a problem that only happens if I push the car to red line if i only rev to 4000rpm there is no issue but if i go beyond to 6000 the car will start to chug and miss fire badly and then I straggle to get to 40mph, there are no error lights on the dash that appear at the time but its like its running on one less cylinder. If I pull over turn the car off and then turn back on then its fine again.

To me it seems that something is reading wrong when the car is pushed to full power and then causes it to over fuel or under fuel causing it to misfire but not sure, I would appreciate any help to diagnose this.
Sorry if I am a bit confused here - so please excuse my questions.

1) Do you actually get full power - 7000 revs? If you do then it will "bounce" off the rev limiter and give the symptoms you describe.

2) If you are revving to the limit but doing 40mph - which gear are you in?

3) If, when this happens you lift off does the car drive normally or do have to stop to restore things to normal?

As I say - sorry for the questions but the answers may help us help you.
 

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Discussion Starter · #3 ·
sorry if my post seemed a bit confusing.

basically if drive the car fast through first gear to full revs and then change to second gear the car will then loose power and misfire badly until I turn it off and on again. it may take a few attempts before it happens but will happen after a few redlines in a couple of gears basically when under heavy load.

If i just drive normally at normal speed and change gear every 3 to 4000 rpm then i have no problems.
 

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sorry if my post seemed a bit confusing.

basically if drive the car fast through first gear to full revs and then change to second gear the car will then loose power and misfire badly until I turn it off and on again.

If i just drive normally at normal speed and change gear every 3 to 4000 rpm then i have no problems.
Got It!

Hopefully someone here will have some ideas.
 

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My son hit the limiter in his V6 last week and it cut out completely and would not run afterwards although it did start and cut out. RAC man plugged it in and up came MAF sensor fault. Unplugged the sensor and the car ran and was driven home. Try unplugging the MAF to see if it changes your symptoms.

PS Glad to see you said you were in first or second or us V6 owners would have known how much you were breaking the law by :lol:
 

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My son hit the limiter in his V6 last week and it cut out completely and would not run afterwards although it did start and cut out. RAC man plugged it in and up came MAF sensor fault. Unplugged the sensor and the car ran and was driven home. Try unplugging the MAF to see if it changes your symptoms.

PS Glad to see you said you were in first or second or us V6 owners would have known how much you were breaking the law by :lol:
I hit the limiter in second a few times when I first bought the V6, so easy to do until you learn, but luckily for me it never threw up these symptoms.
 

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Discussion Starter · #7 ·
I'm not actually hitting the rev limiter just changing gear at the optimum time, I thought about it being the MAF sensor but then I thought I should get symptoms even at lower speed not just on full load.
 

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I'm not actually hitting the rev limiter just changing gear at the optimum time, I thought about it being the MAF sensor but then I thought I should get symptoms even at lower speed not just on full load.
Not necessarily, it might just be giving the wrong values at high revs. A run with it unplugged won't do any harm.
I've never really found an optimum time to change up, it just seems to keep on going.
Just for the record my son and his two mates are regulars on the limiter also previously with no ill effect.
I've hit the limiter twice in mine, once when I was in second.... the other when I wasn't :tut:
 

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+1 Funny this should come up, I was only saying to my friend today how on most cars you can tell when you're getting near the red line. The volumetric efficiency tends to drop off and you can feel the power dropping; I don't ever get that with the GTV, and yes I hit the rev limiter frequently! I did have a problem with the MAF, went through 2 (genuine Bosch) in first couple of months due to air box lid only having 2 studs; you might want to check yours.
 

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I've never really found an optimum time to change up, it just seems to keep on going.
It's meant to be at 6200 revs apparently - and that is what I have always done - apart from the odd occasion when overtaking in second and hitting 7k because it arrives so quickly.
 
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