Z32 Engine revving high on cold start

Nistune topics related specifically to the 6303 cpu

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RobH
 

Posts: 56
Joined: Wed Nov 21, 2007 5:38 am

Z32 Engine revving high on cold start

Post by RobH »

Hi guys,

Is there a table that controls the engine speed on startup? To explain, when I start the car (300ZX VG30DETT Z32) from cold it instantly revs up to about 4K, almost as though I've started it with my foot on the accelerator. Obviously this doesn't sound good and does the engine no favours at all, revving high before the oil has had chance to circulate.

Injectors have been resized and the related tables auto adjusted. I don't want to go making changes to tables I should be leaving alone ;-)

Thanks in advance for any advice.

RobH
TM_S13
 

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Joined: Mon Dec 29, 2008 11:29 pm

Re: Z32 Engine revving high on cold start

Post by TM_S13 »

was it fine before the injector change ?
have you tempered with the TPS sensor ?
Matt
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Re: Z32 Engine revving high on cold start

Post by Matt »

sounds like air leak more than ECU tuning issue

what is your timing when it is this high?

is your TPS idle light working as it should

it shouldnt idle that high without extra airflow to compensate, otherwise it would just run too rich. even with extra timing i doubt it could reach 4K
RobH
 

Posts: 56
Joined: Wed Nov 21, 2007 5:38 am

Re: Z32 Engine revving high on cold start

Post by RobH »

Ta for the replies, think my spam filter blocked the notifications hence my late reply.

It was ok prior to injector change from Venom 550cc to Nismo 555cc, I reset everything up again after this. I'm sure the TPS is set right but it wouldn't hurt to double check.

To stress the point, it only revs high instantaneously and then immediately drops back to about 1500 - 2K, a bit like a long blip of the throttle. It doesn't do this when warm.

The timing is advanced a little from the stock map but only in the last four columns and not in the lower rows.

Cheers
H
Matt
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Re: Z32 Engine revving high on cold start

Post by Matt »

whats the timing look like in your log files?

scan you do a capture of the problem in 'stream mode' and post here for us to see?
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