Power dip when cold...

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Li7hium
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Power dip when cold...

Postby Li7hium » Tue Feb 13, 2007 11:02 am

Hey guys,

I've started noticing more and more a significant power dip when I am accelerating on a cold or cool start. Idle is fine and moving around at slow speed is fine, but as soon as I start pushing about 50% throttle or so, it feels like someone has just turned the air con on, with the power dip and it takes a few seconds, and backing off the throttle, to get it to come back on full power.

And NO, the a/c is NOT on at the time.

Any ideas?

Matt
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16bit
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Postby 16bit » Tue Feb 13, 2007 11:22 am

i have the same thing but it has always been like that. when it warms up its fine (about a minute of normal driving). Maybe the ecu is retarding the timing until it gets to a certain temp for some reason.
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StanTheMan
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Postby StanTheMan » Tue Feb 13, 2007 11:55 am

I'd be looking at the O2 sensor.
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Postby Boags » Tue Feb 13, 2007 1:25 pm

Sounds like leads to me... How old are they?

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Postby Li7hium » Tue Feb 13, 2007 1:27 pm

Leads are about 90K kms old, as it turns out.

And before anyone asks, yes the petrol tank is full!

:mrgreen:

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Re:

Postby Boags » Tue Feb 13, 2007 1:37 pm

Li7hium wrote:And before anyone asks, yes the petrol tank is full!


Yep, that would have been my next question... :oops:
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sabretooth
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Postby sabretooth » Tue Feb 13, 2007 8:09 pm

I'm inclined to think it's the AFM or the TPS. The O2 sensor is not used under acceleration...
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Postby Li7hium » Tue Feb 13, 2007 8:10 pm

OK, lets dumb it down for the less mechanically minded, moi included.

AFM?

TPS?

Thanks,

Matt
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Re:

Postby Boags » Tue Feb 13, 2007 8:12 pm

Li7hium wrote:OK, lets dumb it down for the less mechanically minded, moi included.

AFM?

TPS?

Thanks,

Matt


AFM = Air Flow Meter

TPS = Throttle Position Sensor

I'd still bet your left nut it's leads. Not mine though. :shock:

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Postby sabretooth » Tue Feb 13, 2007 8:35 pm

Boags has a good point - as leads deteriorate they won't be able to ignite the spark in denser or higher-pressure mixtures.


Do that first.


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Craig
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Re:

Postby Craig » Tue Feb 13, 2007 8:47 pm

Li7hium wrote:Leads are about 90K kms old, as it turns out


Not a bad effort from a set of Magnacors though! 8)
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Postby JBT » Tue Feb 13, 2007 8:56 pm

....power dip when I am accelerating on a cold or cool start....
That's the symptoms mine had when the leads started to fail.
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Li7hium
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Postby Li7hium » Wed Feb 14, 2007 10:12 am

Difficult job to replace the leads?

I'm thinking of ordering a replacement set of the Magnacors Blue from Mania and doing it myself.

Matt
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Postby Garry » Wed Feb 14, 2007 10:13 am

Easy job. Just replace them one at a time so that you dont get them mixed up.
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Li7hium
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Postby Li7hium » Wed Feb 14, 2007 10:14 am

And are the NGK Iridium IX Spark Plugs still the bees knees? Since I am doing leads, for sake of completeness I should probably do plugs as well.

Matt
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Wakefield 1:14:78 28-6-09! Oran Park GP 1:27:73 30-03-08 Oran Park South 54:50 14-10-2007 Eastern Creek 2:02:44 6-8-07
BRZ
Pheasant Wood 1:05.4940
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