Jump to content
SAU Community

Recommended Posts

Hi All,

I've had some recent issues with my series 1 R33 that has me thinking that the CAS is dying and needs to be replaced, however I'm looking for a second opinion before I go out and source a replacement.

It started running rough the other night on the highway randomly after driving for around 20 minutes. It was running low on fuel at the time, so as it runs on E85 I assumed it was possibly picking up some water/crud from the tank and limped it over to a mates house quickly. After filling it up with a jerry can of E85 about 30 minutes later, I started it up and gave it a rev and all was fine once again. I ended up driving it back home about 5 hours later and it didn't have any problems for the remainder of the drive (about 30 minutes).

Fast forward to yesterday and my old man takes it for a drive after its sat for a day or two and once again it runs fine for about 15 minutes then starts running really rough. I looked over it yesterday after its been sitting for about an hour and it's still running rough this time. I end up replacing the fuel filter just in case its clogged up and there is no change - fuel pressure at the rail is around 44psi which is spot on apparently and I cannot see any problems with the fuel system (has an E85 460lph Walbro installed). I move onto the spark plugs which appear to be fine and then check and replace the coil packs with known good spares to check that a coil hasn't died and it makes no difference (currently has ~2 month old yellow jackets). I then attempted to disconnect a plug for each cylinder to determine if there was a particular cylinder dropping but it doesn't seem to be any particular one. I also checked the ECU (Link G4+ plugin) which doesn't register any relevant error codes.

After another hour or so of checking lines, wiring, etc I start it back up and its now running worse than ever - barely idling and struggles to rev at all (feels like all the timing has been pulled).

Based on the above I assume its the CAS that's dying, however would love a second opinion/sanity check of the above!

TL;DR;

RB25DET running badly

Initially only happening after 10-15 mins of driving, now all the time

Have checked ECU, plugs, coil packs, fuel filter, fuel pressure

Assume CAS is dying and want a second opinion

Log your voltage with your ECU, see if the voltage drops as you drive in the higher rpm area.

I had a similar issue where my car would splutter and shit whenever it was warm.

Turned out my alterntor was cactus and voltage dropped to 12.2 volts after 4000rpm or so

So you have the software for the link on a laptop? I would start by looking at everything you can on the link software wbile while its having the problem. In one of the top drop down menus there is 'view parameters' or something along those lines which has a heap of tabs with all the stats of the car. Start with that

Have you done simple things like pulling individual coilpack plugs out while running to see if one doesnt change the engine note.

You can idividually check injectors in the link software. I think in aux outputs - fuel there is an injector test option

The link software is great for testing outputs. Can check whats working (options for test pwm or test that just turns it on)

Depends...I replaced a CAS on an RB25DET which was running rough. When we got the CAS off it felt like a stuffed wheel bearing - turned roughly and sometimes caught almost solid.

  • 4 weeks later...

For anyone that cares it turned out to be the ignitor.

I bought a replacement ignitor from a parts shop that was supposed to be "tested in working condition", but it seems it was just as broken as the one I had on. Workshop put a brand new one on and it runs perfectly now.

  • Like 2

Also FYI

I had the exact same issues on my 34.

34s ingiter is built into the coilpacks.

My issue was related to my injectors being blocked from E85 when i change my engine with a different fuel tank, same symptons as you.

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

    • Back again. I returned to Japan in Jul/Aug to spend time with the car on my birthday and remind myself what all the sacrifice and compromise is for. It happened to line up with the monthly morning meet in Okutama, which I have been wanting to go to for a long time. It's a unique event at a unique spot with really rare, interesting, and quirky cars. It's where all the oldheads and OGs gather. The nighttime scene at DKF certainly has its place and should be experienced if you're into cars, but there's too much bad attention and negativity around it now. IMO the better time is Sunday morning at DKF or Okutama; it's more chill and relaxed. I'm glad I was finally able to go, but not sure it's worth the drive from all the way from Nagoya immediately the day before, unless I was already staying in Tokyo for the days right before the meet, because you have to wake up quite early to make it in time. Funnily enough though I didn't drive the car all that much this trip because it was just too damn hot. While there were zero issues and running temps were nominal and the A/C was strong, RBs already run crazy hot as it is. Sure, it took it all like a champ but something about driving these cars in the ridiculous heat/humidity bothers me and makes me feel like I'm asking too much of it. I'm just me being weird and treating the car like a living thing with feelings; I'm mechanically sympathetic to a fault. Instead I was mainly driving something else around - a KX4(silver) 2001 X-Trail GT, that I acquired in May. There's a few different flavors to choose from with Xs, but visually it's the Nissan version of the Honda CR-V. Mechanically it's a whole different story as this, being the top-trim GT, has an SR20VET mated to a four-speed auto and full-time AWD! It was a very affordable buy in exceptional condition inside and out, with very low mileage...only 48k kms. Most likely it was owned by an older person who kept it garaged and well-maintained, so I'm really happy with how it all worked out. It literally needs zero attention at the moment, albeit except for some minor visual touch-ups. I wanted something quirky, interesting, and practical and for sure it handily delivers on all three of those aspects. I was immediately able to utilize the cargo and passenger capacity to its full extent. It's a lot of fun to drive and is quite punchy through 1st and 2nd. It's very unassuming -in the twisty bits it's a lot more composed than one would think at a glance- and it'll be even better once I get better tires on it(yes, it's an SUV but still a little boat-y for my liking). So...now I have two golden-era Nissans in silver. One sports car and one that does everything else; the perfect two-car solution I think👍 The rest of the trip...I was able to turn my stressed brain off and enjoy it, although I didn't quite get to do as much as I thought. I did some interesting things, met some interesting people, and happened into some interesting situations however, that's all for another post though only if people really want to know. Project-wise, I went back to Mine's again to discuss more plans and am hoping to wrap that up real soon; keep watching this space if that interests you. Additionally, while working in the tormenting sweatbox that is the warehouse, I was able to organize most of the myriad of parts that my friend is storing for me along with the cars, and the 34 has a nice little spot carved out for it: And since it can get so stupid hot in there, that made it all the more easy -after I was standing there looking at the car and said 'f**k it'- to finally remove all the damn gauges that have mostly been an eyesore all this time. Huzzah. The heat basically makes the adhesive backing on the gauge mounts more pliable to work with, so it was far less stressful getting this done. I didn't fully clean it up or chase the wiring though; that will happen once I have the car in closer possession. Another major reason to remove all that stuff is to give people less reasons to get in my car and steal s**t while it's being exported/imported when/if the time comes, which leads us to my next point... ...and that is even though it's time in Japan is technically almost up since it's a November car and the X would be coming in March, I'm still not entirely sure where my life and career is headed; I don't really know what the future looks like and where I'm going to end up. I feel there's a great deal of uncertainty with me and as a result of that, it feels like I'm at a crossroads moreso now than any point in my life thus far and there are some choices I need to make. Yes, I've had some years to consider things and prepare myself, however too much has happened in that time to maintain confidence and everything feels so up in the air; tenuous one might say. Simply put, there's just too much nonsense going on right now from multiple vectors. Admittedly, I'm struggling to stay in the game and keep my eyes on the prize. So much so in fact, that very recently I came the closest I ever have before to calling it quits outright; selling everything and moving on and not looking back. The astute among you will pick up on key subtext within this paragraph. In the meantime I've still managed to slowly acquire some final bits for the car, but it feels nice knowing there's not much left to get and I'm almost across that finish line; I have almost everything I'll ever want for my interpretation and expression on what it is I think an R34 should be. 'til later.
    • Thanks for that, hadn’t used my brain enough to think about that. 
    • Also playing with fire if they start to flow more air down low than what the stock twins can. It's not even up top you need to worry, it can be at 3000rpm and part throttle and it's getting way more flow than it should.
    • Any G40/1000 or G40/1250 results out there?  
    • You still want a proper tune on the stock ECU though. Stock tune + stock ECU with GT-SS/-9s is probably playing with fire if you're running more than stock airflow/power.
×
×
  • Create New...