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My r32 with rb25 conversion won't idle after doing a highmount conversion. It will rev fine and pull great. Light throttle coasting it will miss and carry on and it won't idle at all, just dies. I tried different afm. Cleaned aac. Checked all cooler pipes. Checked vac lines that I can see. Took Bov off and blocked vac lines. it idled before I did highmount swap

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Ok. I am going to assume you changed the turbo, as swapping manifolds tends to suggest that. And as you didn't mention tune, I will assume that no tune was involved. My diagnosis, based on little info and taking a wild guess.... you killed the engine. (broken rings/ ringlands/ head gasket from pinging)

Unless you have more info to add we can only guess.

Edited by superben
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Ok. I am going to assume you changed the turbo, as swapping manifolds tends to suggest that. And as you didn't mention tune, I will assume that no tune was involved. My diagnosis, based on little info and taking a wild guess.... you killed the engine. (broken rings/ ringlands/ head gasket from pinging)

Unless you have more info to add we can only guess.

I've broken one of my rings and I occasionally get some blue smoke coming out the tail pipe... My car occasionally has this issue where if I clutch in at high revs, the revs will fall till it hits 0 and stalls... Do you think the 2 issues are related?

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That doesnt mean much

Has the turbo been upgraded and was it just thrown on and hope for the best?

is it a stock engine and how many kilometres. It still could have cracked a ring land but hopefully for your sake its probably just not tuned properly

Edited by ido09s
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this isnt entirely true because the AFM will read more air flow on adjust fuel mixture on idle etc etc etc

Ah I forgot about afm. Been running a map to long to remember haha. Still shouldnt be a problem at steady idle though?

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I highly doubt the engine would draw more air at idle just because it has a larger turbo on it..... but stranger things have happened and the inlet could have had some affect on the air flow through the AFM if its running one which has caused it

Edited by ido09s
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it can happen as all air is drawn through the AFM even on idle and thus bigger turbo takes more air (idle or not)

im not say this is the issue however food for though as we still do know any further information to help diagnose

I have to disagree with that. I can't see how the turbo that's not bring driven enough by the exhaust would have any effect at idle. If you pulled the afm off a nice running car and took apart turbo system then put afm onto throttle body I bet it would idle fine.
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