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Old 20th December 2008, 00:12   #1
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Default Loss of power in 1st gear

My UVA has done about 11 k kilometres now.

In heavy bumper to bumper traffic, if I've been alternating between 1st and 2nd gear for some time, there is sometimes a momentary loss of power in 1st gear.

This happens just when after I engage clutch and accelerate to get the car moving from a standstill. Does not happen when the car is moving. The engine keeps running but the car just doesn't respond and the engine vibrations die down to idling level.

If I disengage and engage clutch again, the problem disappears.

It has happened only a few times so am wondering if it is worth spending the minimum of two hours I will need to go to the service centre.

Any ideas anyone?
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Old 20th December 2008, 08:26   #2
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it will happen if you leave the clutch before revving the engine!
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Old 20th December 2008, 09:29   #3
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Quote:
Originally Posted by headers View Post
it will happen if you leave the clutch before revving the engine!
with you. but i believe this should be checked from garage.
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Old 20th December 2008, 11:42   #4
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Could be a case of clutch overheating ? Do you ride the clutch ? try to avoid that.
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Old 20th December 2008, 11:45   #5
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Get the clutch play checked. Sounds like the clutch is little loose. Is it a hydraulic clutch by any chance?
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Old 20th December 2008, 12:11   #6
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Thanks for the opinions, guys.

Quote:
Originally Posted by headers View Post
it will happen if you leave the clutch before revving the engine!
I know, however it seems that's not the case here. The engine doesn't stall but just doesn't respond to the accelerator for a moment. And it is a recent problem with no change in my driving style.

Quote:
Originally Posted by esteem_lover View Post
Could be a case of clutch overheating ? Do you ride the clutch ? try to avoid that.
No, I don't ride the clutch. Am particular about that too.

Quote:
Originally Posted by vikram_d View Post
Get the clutch play checked. Sounds like the clutch is little loose. Is it a hydraulic clutch by any chance?
No, as far as I remember the UVa doesn't have a hydraulic clutch. Thinking back I am wondering if the problem is more to do with the accelerator or fuel transmission.

Looks like I had better play safe and go get it checked. Cheers.
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Old 22nd December 2008, 10:02   #7
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Just guessing here - but its possible that your fuel cutoff (closed to open loop, happens when you leave the accelerator) is not sync'ed with the throttle position sensor properly. So, if your foot relaxed on the accelerator for a moment, it would cut the fuel and then it would again take a moment to go into closed loop when you press the accelerator.

Gurus can advise. (I may be completely wrong here! - let me know).
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Old 22nd December 2008, 10:34   #8
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Quote:
Originally Posted by the_maassk View Post
Just guessing here - but its possible that your fuel cutoff (closed to open loop, happens when you leave the accelerator) is not sync'ed with the throttle position sensor properly. So, if your foot relaxed on the accelerator for a moment, it would cut the fuel and then it would again take a moment to go into closed loop when you press the accelerator.
Not a guru, but I get the same feeling. Either its clutch or it is some problem related to fuel or ignition. I think that the chances of clutch being the culprit here is less but the real issue is fuel cut off.
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Old 22nd December 2008, 10:45   #9
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Quote:
Originally Posted by the_maassk View Post
Just guessing here - but its possible that your fuel cutoff (closed to open loop, happens when you leave the accelerator) is not sync'ed with the throttle position sensor properly. So, if your foot relaxed on the accelerator for a moment, it would cut the fuel and then it would again take a moment to go into closed loop when you press the accelerator.

Gurus can advise. (I may be completely wrong here! - let me know).
AFAIK, the system goes into open loop only at 3/4ths throttle and WOT, other time it is in closed loop. When you let go off the A pedal, the IACV controls the idle RPM and the air flow.
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Old 22nd December 2008, 10:56   #10
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I have a ScanGauge II installed on my U-VA. From what it reports - at least on my ride, the system goes into open loop at 3/4 throttle AND every time I release the accelerator, if I am on the move (and using engine braking to slow down; clutch not depressed). If I hit the clutch while I am coasting on momentum, the system goes into a closed loop.
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