R33 not running properly

[Sean0312]

Hi guys

So I just bought myself a series 1 r33. Car is bone stock except for splitfire coils. For some reason if I’ve been boosting around a little bit, it’ll start to run like crap, it’ll feel like it’s choking upon boost and sometimes cuts out. When this happens, the car will also go into limp mode on idle and will start stalling on me. I’ve changed and gapped plugs, cleaned out maf, had a pretty good look at vacuum lines and checked for leaks. The car had a bolt in the o2 sensor socket on the dump so I’ve put a Silvia o2 sensor in (not sure if they’re the same?) and still has the same issue. Car will run mint under the first few boosts and then will start to run pretty poorly.  
 

Any help would be much appreciated, thanks!! 

[tridentt150v]

What mods do you have....sounds like R&R to me.  So too much boost for a standard ECU, so it tries to compensate to 'protect' the motor.

To raise boost and power you need supporting mods, there is no such thing as cheap power unfortunately.

 

 

[Sean0312]

10 minutes ago, tridentt150v said:

What mods do you have....sounds like R&R to me.  So too much boost for a standard ECU, so it tries to compensate to 'protect' the motor.

To raise boost and power you need supporting mods, there is no such thing as cheap power unfortunately.

 

 

It’s completely stock, even has the stock side mount. Not after “cheap power”, just want a car that runs properly before I start modifying it.  I’m still running the factory boost solenoid without an aftermarket controller. My boost pressure doesn’t reach any higher than 6-7psi according to the factory gauge on the cluster. 

[GTSBoy]

Coils.

Did the S1s still have the igniter? If so, igniter.

AFM solder joints, just possibly getting crackly when the engine bay gets hot.

Same with CAS, CAS connector pins, coil wiring, etc.

[ehnto]

Doesn't sound like R&R because it's having idle issues as well. If it has nothing but splitfire coils it makes you wonder why they upgraded the coils. Perhaps they were trying to solve the same issue, so I would check the ignitor if you have one and coil wiring. You can get a headstart by checking which coil is failing in particular by unplugging each one when it's running rough and listening for a lack of change. No change when it's unplugged means it wasn't working to begin with.

You could also try running without the coilpack cover as a temporary fix, could lower the coil temp enough to keep it running better if coils are the issue.

Can do the same thing with injectors, and you can pull the spark plugs to see if one cylinder is markedly different to the others.

[GTSBoy]

1 hour ago, ehnto said:

You could also try running without the coilpack cover as a temporary fix, could lower the coil temp enough to keep it running better if coils are the issue.

If it's missing at idle because something (a coil or the igniter) is hot then you can try to cool each one down with compressed air while it's missing to see if it comes good.

[Sean0312]

21 hours ago, GTSBoy said:

Coils.

Did the S1s still have the igniter? If so, igniter.

AFM solder joints, just possibly getting crackly when the engine bay gets hot.

Same with CAS, CAS connector pins, coil wiring, etc.

My one doesn’t have an ignitor, not sure if it’s supposed to? I’ve had a look at the coils, no visual cracks or anything suspicious. Might test the resistance in them however I’m not sure if that’ll give me a 100% answer as to whether they’re faulty or not. 
 

Will also have a look at the solder joins in the AFM to make sure they’re OK.

 

6 hours ago, ehnto said:

Doesn't sound like R&R because it's having idle issues as well. If it has nothing but splitfire coils it makes you wonder why they upgraded the coils. Perhaps they were trying to solve the same issue, so I would check the ignitor if you have one and coil wiring. You can get a headstart by checking which coil is failing in particular by unplugging each one when it's running rough and listening for a lack of change. No change when it's unplugged means it wasn't working to begin with.

You could also try running without the coilpack cover as a temporary fix, could lower the coil temp enough to keep it running better if coils are the issue.

Can do the same thing with injectors, and you can pull the spark plugs to see if one cylinder is markedly different to the others.

That’s a good point. I’ll even see if I can pick up/try out a coil harness. I unplugged the o2 sensor yesterday when it was in limp mode and struggling to idle at all. The car started to idle nicely, however it remained to idle smoothly once I plugged the sensor back in. Will try the same with the coils.
 

A couple of the cylinder walls have a bit of rust, although I was told that was not uncommon. Other than that, there isn’t any drastic changes between them.

 

EDIT: 

Another thing I noticed when I was pulling off my cooler piping tonight was that it all smelt really fuely, I’m sure that’s related to the issue? 

Edited May 28, 2020 by Sean0312

[GTSBoy]

57 minutes ago, Sean0312 said:

no visual cracks or anything suspicious.

Cracks not required.

[Sean0312]

UPDATE: ended up fixing the issue, thanks for the help everyone! 
 

I would say it was a couple of things. Previous owner forget to tighten up the hose clamp into the fuel filter so there was a leak. In the process of diagnosis I installed a 255 fuel pump and changed my AFM cause I had a feeling it wasn’t 100%. One of the retainers in the coil plugs had fallen out so I’ve temporarily cable-tied the plug into the coil to prevent it falling out.