Jump to content
SAU Community

Recommended Posts

Hi guys,

First up I own a 98 R33 S2 GTS25T Skyline with the following mods:

HKS Cat back exhaust

De-cated

Pod Filter

GFB Hybrid BOV

I've noticed a oily smell incabin... partically when i'm slowing down or have just been giving it a bit of stick. I changed the oil about 4,000km's ago with Shell Helix 5w40. This problem has only seemed to arise since I've de-cated the exhaust?

Any ideas what it could be?

Link to comment
https://www.sau.com.au/forums/topic/214551-r33-s2-oily-smell-incabin/
Share on other sites

Check that you haven't caused any exhaust leaks during your decating process (did you replace gaskets) Do this by letting the system cool down completely and rub 50/50 dishwashing liquid and water over the flanges. Then start the car and look for bubbles...

Yeah, I'm not sure about the gaskets - An exhaust guy fabbed it up and installed it.

I guess I'll jack my car up tonight and unbolt it and have a look.

Cheers mate, also I was looking at some Fuchs 5w40 oil, whats that like for a RB25DET?

Edited by dekodE_

FWIW there are heavy penalties for removing emissions equipment (ie decat) for a car that's used on the road. A high flow (magic cat/metal cat/catco) style cat shouldnt restrict power at all on your setup, and will reduce the smell and the amount of black crap that will end up on your rear bar.

you may also have a leaking rocker cover gasket. usually passenger side. the oil gets onto the block, and when boosting around, the higher block temps burn the oil and you can smell it quite a bit.

what the f is FWIW?

lol ...for what its worth

Edited by Munkyb0y
Fuchs is fuching good stuff! :) Pricey but worth it.

Sweet, I think its about $79 for 5L which isn't too bad. I might grab some tommorrow.

Had a look in the engine bay for any leaks, and tried to "sniff for oil" couldn't find anything.

Then I took the car out for a spin, It was only really noticeable once I had come to a stop (So i'm still thinking it's an exhaust leak as first suggested, guess I'll jack the car up tommorrow and check it out.

My current oil level hasn't changed, and my car doesn't smoke at all, even on boost... :laugh:

Edited by dekodE_
The rubber seal around base of your gear shifter might be split. That will give off an oily smell in the cabin.

exactly what i was goin to say..my car had a short shifter in it when i bought it but i didnt like it so i bought a gtr shifter to replace it..when i went to take out the short shifter i found the previous owner had put a tea towel around it to stop oil spiting out which stoped the smell getting to the cabin and the short shifter had no seal..so i had to buy a seal from nissan when i put the gtr shifter in and i removed the tea towel..i had an oily smell in my cabin for round 2 weeks but its gone now :D

Interesting idea's being thrown about when OP said...

...This problem has only seemed to arise since I've de-cated the exhaust?...

Every cat'less car i know has a particular smell to it. Hard to describe. When idling, and a breeze blows the fumes into the cabin, smells kinda oily i guess; sure its not just that?

If your sure it only started when you ripped the catback off, smashed the china out of the cat and shlaped it back on... then start there first.

LoL @ Luciano_GTST.... Google will tell you all abbreviations ;)

Edited by GeeTR

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • GCG is a good company, they're a major distributor for Garrett in Japan as well.
    • Nah, OEM washer bottle and brake fluid reservoirs are fine I don't know what it is with the plastic that Mazda used, some plastics, like the washer bottle and brake fluid res are fine, and still look new after 20 years use, where as the coolant expansion tank, and PS reservoir, that I replaced with new OEM items when I first got the car, turned yellow and started getting brittle a few years later If the dirty yellow stained plastics didn't trigger me there wouldn't be an issue, but they did, much like the battery bracket....... Meh As for going back to work full time to support car stuff, nope, why, because I own a Mazda NC MX5, not a Nissan R series Skyline 🤣
    • I've never heard of CJ-motor, so can't advise you on them. I'd just go straight to GCG for a GCG highflow though. Seems no point to use a middleman. I'm somewhat surprised that the price on the CJ site is lower than the GCG retail price. Even though CJ would get a discount of some sort, you would hardly expect them to give up so much margin. Maybe the price is out of date? Having said that "I'd go to GCG"...when I did my highflow, I went to Hypergear. I did this https://hypergearturbos.com/product/rb25dethighflow/#tab-dyno-results with the R34 OP6 450HP profile. With the BB centre (extra $400) and intially with the standard boost actuator, but I eventually got him to send me the high pressure one when I got to the point of being able to actually use it. Ends up costing the same sort of money as the GCG highflow, but this is, of course, the turbo that I KNOW has a shorter length core and so moves the comp cover rearwards. The GCG apparently doesn't do that. My mechanic also swears by the GCG highflow, given that we have another turbo rebuilder who does something essentialy the same as theirs, using Garrett wheels. He says it stands up at really low revs and makes good power. I haven't pushed my HG highflow past ~240-250rwkW yet (should have a little more in it, but unclear how much) and it does have a fairly gentle boost ramp. OK, it's much better now that I have gotten my boost controller tuned up on it.  A lot of my earlier unhappiness was because I couldn't keep the wastegate flap as closed as it needed to be (including some mechanical issues). I'd still prefer it to boost up nearly as quickly as the stocker, and it certainly a bit slower than that. So maybe the GCG one is worth the first look (for you).
    • Ok thanks 🙂 I will higly consider this. Any "known" company for a good reviews and experience to send that off? Is that CJ-motor good one? Or go straight to GCG site? I need to use VPN to even find some of those "shops" let alone access them 🙂 
    • You can literally put in as much WMI as it takes to quench the combustion totally (and then back it off a little, obviously), and it will keep making more and more power. The power comes from the cooling effect of the water (and the meth) and the extra fuel (the meth, which also has massive octane). It is effectively exactly like running E85. One might be slightly better than the other, but they are damn close. But with either you can lean on the boost or the timing (or both) waaaay more than with just petrol and the results are similar. Here's the first thing I googled for an anecdotal bit of evidence. Can't access the attachment without being a gold member, but it is there for the getting if able to, or searched up elsewise perhaps. https://www.hpacademy.com/forum/general-tuning-discussion/show/wmi-vs-e85/
×
×
  • Create New...