Engine start problem

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speedmaster
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Engine start problem

Postby speedmaster » Thu Aug 06, 2015 9:04 pm

I'm not sure if anyone has this problem.

Bone stock 20v Blacktop. Cold morning start easy like a charm. But when its warmed up, it needs to be cranked 1-2 seconds before it starts. Other than that, engine runs well. I have tried changing 255lph fuel pump but didn't solve it. Anyone can share some advice?

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Re: Engine start problem

Postby gotzoom? » Fri Aug 07, 2015 1:07 pm

IAT sensor ok and mounted either in an intake plenum or near the inlets of the ITBs?

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Re: Engine start problem

Postby speedmaster » Fri Aug 07, 2015 5:10 pm

gotzoom? wrote:IAT sensor ok and mounted either in an intake plenum or near the inlets of the ITBs?

Yes. But how to check if it's not OK?

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Re: Engine start problem

Postby speedmaster » Sun Aug 09, 2015 10:33 pm

One respected tuner told me to change the crank sensor to a 4g93

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Re: Engine start problem

Postby gotzoom? » Mon Aug 10, 2015 8:52 am

There is no crank angle sensor on any variation of 4AGE. The factory service manual has the test procedure for the IAT sensor. The ECU uses the IAT temp reading to adjust the fuel mixture, so if it is not reading the same temp as the air entering the throttles, the engine isn't going to run correctly.

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Re: Engine start problem

Postby speedmaster » Mon Aug 10, 2015 9:09 am

gotzoom? wrote:There is no crank angle sensor on any variation of 4AGE. The factory service manual has the test procedure for the IAT sensor. The ECU uses the IAT temp reading to adjust the fuel mixture, so if it is not reading the same temp as the air entering the throttles, the engine isn't going to run correctly.

IAT sensor, I unplugged it and there is no CEL. I will run a diagnosis.

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Re: Engine start problem

Postby allencr » Mon Aug 10, 2015 11:24 pm

Will it start quickly if the throttle is held 1/3-2/3 open?

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Re: Engine start problem

Postby speedmaster » Mon Aug 10, 2015 11:29 pm

allencr wrote:Will it start quickly if the throttle is held 1/3-2/3 open?

It won't.

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Re: Engine start problem

Postby speedmaster » Mon Aug 10, 2015 11:52 pm

allencr wrote:Will it start quickly if the throttle is held 1/3-2/3 open?

Maybe just a little effect. Minor