Rb25det Hcr32 idle issue

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Tengis
 

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Joined: Thu Oct 23, 2014 2:21 am

Rb25det Hcr32 idle issue

Post by Tengis »

Has 720cc injectors and Z32 maf. I fixed idle tps trigger and set the injectors + MAF in Nistune.

Engine won't idle without injection multiplier up around 500-600 from the 150 or so that it is sweet to after initial adjustments. Once I got it running, it will abruptly die after it's running for 15-20 seconds.

I haven't had much time to troubleshoot but I will tomorrow when I hook up my wideband.

The vct sensor isn't wired up yet but the light blinks in Nistune while scanning when it dies... related?
bachig24u
 

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Re: Rb25det Hcr32 idle issue

Post by bachig24u »

Post the tune bin file. Let's have a look.
Tengis
 

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Re: Rb25det Hcr32 idle issue

Post by Tengis »

I went full retard: the intake tube fell off the MAF.

Idle is still a little rough though. I think the injectors I have are stock "high flowed" side feed injectors... you guys ever dealt with these?
bachig24u
 

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Re: Rb25det Hcr32 idle issue

Post by bachig24u »

Best take the injectors out and get them flow tested.

I haven't seen a set yet that would pass as a matched set.
Tengis
 

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Re: Rb25det Hcr32 idle issue

Post by Tengis »

I always thought the worst of it was that the spray pattern was garbage?

I'm going to just look for a stock set or go with top feed.
bachig24u
 

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Re: Rb25det Hcr32 idle issue

Post by bachig24u »

spray pattern changes with fuel pressure so no big deal... BUT...

flow matching is critical along side the operating fuel pressure pattern delta as you mentioned.

Some injectors just don't suit the manifold angles or port design after a flow modification.
Uncontrollable mixtures in certain load/rpm ranges can be attributed to the spray patterns.
Basically a build up of fuel that's not atomising very well and ends up on the intake tract walls. (TAU factor)

Overall I would prefer to work with flow matched injectors over good/bad spray patterns,
as long as the patterns are consistent across all injectors.
Tengis
 

Posts: 38
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Re: Rb25det Hcr32 idle issue

Post by Tengis »

I got the initial issue fixed.

Now the fuel pump is doing some weird surging at idle. I crawled under the car and the feed line is actually pressurizing and slightly depressurizing at idle. The fuel pump control module controls this, correct? I am not intimate with this platform on that level so Im not sure if this is an issue with the pump or something with the control module.
bachig24u
 

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Re: Rb25det Hcr32 idle issue

Post by bachig24u »

The HCR32 ECU uses the FPCM to lower pump voltage when TPS is 'ON'.
Make sure TPS light is not flicking on and off.
Tengis
 

Posts: 38
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Re: Rb25det Hcr32 idle issue

Post by Tengis »

It's not flickering, it's solid.
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