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problems after installing new FMIC

Munna

By Munna,
in Engines & Forced Induction

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Munna Rising Star

Munna

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Yesterday I install a brand new Hybrid FMIC to my r33 gtst.

about 12 months ago I had a SAFC installed and tuned as I had flat spots (running to rich) the SAFC fixed that problem.

I had being running 10psi before the cooler was installed but now I cant run anymore than 7 or the car seems mess and cough under load. I think this may be due to incorrect setting on my SAFC because now im getting so much more cool air. Do you need to get your SAFC retuned after the installation FMIC? Or am I on the wrong track what else could cause this?

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Munna Rising Star

Munna

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Using a FMIC will mean cooler inlet temps, so your SAFC may need a touch up tune.

Although the coughing and missing sounds like a spark plug issue.

Do you know what type of plugs you have and what size gap they are ?

J

Plugs are near brand new gapped at 0.8. pretty sure its no thats not the problem because the car was fine before the cooler went on. its hard to explain but the car is no realy missing its more of a hesatation might be a boost cut or something?

Guest Robo's

Guest Robo's

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Your SAFC will need to be redone but i shouldnt have thought it would make it spluttery. When i done mine it still ran fine with the old settings. I would be checking for leaks, trying clamping it up a bit more. I encountered this after the first test drive with the new FMIC.

Munna Rising Star

Munna

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Checked all my piping connections all were nice and tight with no leaks. Called the guys form Ice performance they think that its probably overfueling again now that the engine is getting cooler denser air so im going to get it retuned Wednesday. I will let you all know how it goes.

rs73 Grand Master

rs73

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Just suggesting something that you should check. I know it doesnt make sense, even in my case, but that's what the solution for mine anyway. I've had my dying pump almost a year before it was detected. On dyno the car made good A/F ratio of around 11.5:1 but tweaking the SAFC just doesn't want to change this. Very weird but the stock ECU seemed to compensate for the lack of fuel and fiddled with the timing. Only found out about the fuel pump when testing the fuel pressure and that's it. Got it changed over to a bosch item and the car is happy now with 12:1 A/F ratio and 192.5rwkw (before it wont go past 152rwkw in any boost level).

Sydneykid Grand Master

Sydneykid

Posted
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Yesterday I install a brand new Hybrid FMIC to my r33 gtst.  

about 12 months ago I had a SAFC installed and tuned as I had flat spots (running to rich) the SAFC fixed that problem.

I had being running 10psi before the cooler was installed but now I cant run anymore than 7 or the car seems mess and cough under load. I think this may be due to incorrect setting on my SAFC because now im getting so much more cool air. Do you need to get your SAFC retuned after the installation FMIC? Or am I on the wrong track what else could cause this?

My guess, freer flowing FMIC means more airflow. More airflow is detected by the AFM and signalled to the ECU which is going into rich and retard (engine protection) mode sometime erroneously called "over boost" protection. You don't need extra boost to get it.

Just my guess of course, based on about 10 Skylines I have seen do exactly the same thing. :D

Munna Rising Star

Munna

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My guess, freer flowing FMIC means more airflow.  More airflow is detected by the AFM and signalled to the ECU which is going into rich and retard (engine protection) mode sometime erroneously called "over boost" protection.  You don't need extra boost to get it.

Just my guess of course, based on about 10 Skylines I have seen do exactly the same thing. :D

Thanks for all your replies Rs73 I will get my fuel pump checked out while it is there.

Sydneykid ive read some of your other posts about over boost protection and it made sense. If I understood correctly when I get my SAFC retuned it should fix the problem as they will be able to minipulate what flow the ECU thinks it is getting. Is that right?

NickR33 Grand Master

NickR33

Posted
Posted
My guess, freer flowing FMIC means more airflow.  More airflow is detected by the AFM and signalled to the ECU which is going into rich and retard (engine protection) mode sometime erroneously called "over boost" protection.  You don't need extra boost to get it.

Just my guess of course, based on about 10 Skylines I have seen do exactly the same thing. :cheers:

I get this exact symptom but ONLY when the car is cold... after almost exactly 15mins of driving it runs fine... go figure

I suppose it will get worse when my FMIC goes in... might have to get it looked at... lol *so lazy*

Munna Rising Star

Munna

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I get this exact symptom but ONLY when the car is cold... after almost exactly 15mins of driving it runs fine... go figure

I suppose it will get worse when my FMIC goes in... might have to get it looked at... lol *so lazy*

Before I got my SAFC mine did a similar thing to what it is doing now only not as bad. you probly need to one to funny it only does it when its cold.

Munna Rising Star

Munna

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Well I took my car to ice performance in melbourne yesterday. Found that I had dirty coil packs and my plugs wern't gapped to 0.8. The last time I took my car to a local macanic I had new plugs put in and I asked them to gap them a 0.8. So all this I thought they were gapped correctly when they were not. very anoyed. Anyway after the coilpacks were cleaned and sparkplugs were regapped the missfiring was gone. So they retuned the SAFC and the result was 196 Kw at the wheels on 10.5 psi of boost. very happy with that result and I recomend Ice performance to anyone.

wilch Grand Master

wilch

Posted
Posted

I'm getting a front mount installed on the weekend.

Apart from full exhaust, pod (in cold air box), and electronic boost controller everything else is stock. Is there anything I should watch out for?

wil..

Munna Rising Star

Munna

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I'm getting a front mount installed on the weekend.

Apart from full exhaust, pod (in cold air box), and electronic boost controller everything else is stock. Is there anything I should watch out for?

Regap plugs to 0.8 install the cooler and see how you go. But you may find installing a SAFC or simmilar will give you a lot better results as your ECU will probably see all the extra air flow and richen your air fuel mixtures with hurts performance big time.

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