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R32 Gtr Running Rich, Suspect Vacuum Leak, Any Thoughts!

Gorilla26

By Gorilla26,
in General Maintenance

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Gorilla26 Apprentice

Gorilla26

Posted
Posted

Hi guys, I have a 32 GTR with a few mods, nistune, 34 afms, unsure on turbos (only just got the car), built motor, 34 crank, camtec cams, etc etc,

The car is running very rich and stalls when I come up to a set of traffic lights, it is running standard bovs, would a vacuum leak cause this to happen? What is generally the cause of a vac leak in an RB26? Are there any common hoses that deteriorate quicker than others?

Thanks!!!

Ben C34 Grand Master

Ben C34

Posted
Posted

Vac leak would make it run lean when off boost if the leak is in the inlet manifold . rich if its a boost leak in a cooler pipe.

Did it always do it@

You should really take it somewhere and run it on a Dyno to check it out.

breaker1845 Community Regular

breaker1845

Posted
Posted

You have the stock bov's but are they actually functioning correctly and plumbed back? If they aren't that is probably your issue.

Run it on the dyno or do a smoke test to find your leaks after checking the BOVs. It could be poorly tuned also contributing with the leak resulting in the car stalling.

Gorilla26 Apprentice

Gorilla26

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Thanks for the help guys, the car previously made 400rwkw then has been put into storage for a while and there are now a few issues to sort out. What vac lines are under the plenum that could have perished or might be leaking???

Duncan Grand Master

Duncan

Posted
Posted

well a smoke test is the best way to get to find a vacuum leak, but it requires specialist equipment. Easiest thing to do is to give it to someone who does this all the time unless you are familiar, there are billions of pipes and they won't be standard on your setup

As far as finding it yourself, I'd start with the main intercooler pipes in the engine bay and under the front bar, they are by far the most likely. They check the BOV return lines wherever they plumb back in. Then the boost controller lines and their attachment to the wastegate. Then however your AAC is linked up, that should cover most of the vacuum lines.

breaker1845 Community Regular

breaker1845

Posted
Posted

If you don't know what it is don't touch it? Got a workshop around that is experienced with Skylines that can help you out? Smoke test and getting the vehicle on a hoist will help significantly.

I'd still put money on it being the BOVs or a combination of BOVs being not plumbed back, broken and the ECU tune being rich to begin with.

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