Jump to content
SAU Community

Misfire problems

AngryRB

By AngryRB,
in General Maintenance

 Share

Recommended Posts

AngryRB Grand Master

AngryRB

Posted
Posted

Currently have annoying misfire problems. The engine is RB30neo, after taking car to reputable tuner he replaced cas with secondhand cas , a coilpack, std fuel reg, fuel filter and said the fuel injectors are dirty and fuel filter was blocked.  So he road tuned car and said its better now.

Original issue was it running like a wrx for first 10mins, after that it was a rocket.

So now after it being at the workshop, it still starts like a wrx and now it has a strong misfire at 4k, right at the point it used to start breaking traction.

So i started it up and pulled one coil out at a time, cyl 3 and 5 not firing.  These coilpacks are brand new, have replaced them twice now.

So my question is what can cause cyl 3 and 5 to randomly not fire? Or are these splitfire coils fake copies?

Link to comment
https://www.sau.com.au/forums/topic/475431-misfire-problems/
Share on other sites
AngryRB Grand Master

AngryRB

Posted
  • Author
Posted
3 hours ago, iruvyouskyrine said:

1. get a new tuner 

2. never seen fake splitfires

3.get your multimeter out and start continuity and voltage checking. Also inspect loom for damage.

Yep that workshop gone to shit for sure.. not happy..

This morning i tried again, and cyl 3 and 5 dead, so i put 2 old coilpacks in and she ran sweet except heavy breakdown under load later when was hot.

So whats the chances of 3 brand new coilpacks failing on a cold start?

Loom is brand new from kudos, plugs new also..

What about the cas or ecu, can they play these kind of games?

I dont really have a clue about multimeter testing.

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

CAS "might" be cooked and the ECU is unable to determine a home signal, i.e. 1x full revolution of the CAS to determine TDC.

This could affect your car starting, however without using any tools it might be hard to diagnose.

 

Maybe try record your PowerFC hand controller with a GoPro or phone and see if there's a RPM when the CAS is rotated OR the car is cranked.

iruvyouskyrine Grand Master

iruvyouskyrine

Posted
Posted
19 hours ago, AngryRB said:

Yep that workshop gone to shit for sure.. not happy..

This morning i tried again, and cyl 3 and 5 dead, so i put 2 old coilpacks in and she ran sweet except heavy breakdown under load later when was hot.

So whats the chances of 3 brand new coilpacks failing on a cold start?

Loom is brand new from kudos, plugs new also..

What about the cas or ecu, can they play these kind of games?

I dont really have a clue about multimeter testing.

The coilpack harness might be new but i bet the main engine loom is not. I would start looking where is passes the exhaust, where it passes through the firewall and around the ECU header plug.

Youtube how to continuity test with a multimeter, its an excellent skill to have and difficulty level is 2/10.

AngryRB Grand Master

AngryRB

Posted
  • Author
Posted
1 hour ago, mr_rbman said:

Sounds like a similar issue i've had...

You running a Z32?!

Yep a z32, today again cyl 5 so i switched it with cyl 6 coil and just like that all 6 firing...

Will start looking into the multimeter idea and the cas test.. 

 

Ben C34 Grand Master

Ben C34

Posted
Posted
4 hours ago, AngryRB said:

Is this plug helping? Last set was a BKR7E that had a split in the electrode

20181123_094525.jpg

20181123_094548.jpg

That's a hot plug man, no way would I use that in a higher boost application (or any boost for that matter)

  • Like 1
mr_rbman Grand Master

mr_rbman

Posted
Posted
On 11/23/2018 at 7:49 AM, AngryRB said:

Is this plug helping? Last set was a BKR7E that had a split in the electrode

 

 

 

On 11/23/2018 at 7:49 AM, AngryRB said:

Is this plug helping? Last set was a BKR7E that had a split in the electrode

 

20181123_094548.jpg

Is it just me or is that plug gap huuuuuge?!?!?!

  • 2 months later...
AngryRB Grand Master

AngryRB

Posted
  • Author
Posted (edited)

Small update, i changed the plugs back to BKR7E and she has all the power back with no misfire's... 

The issue still remains, that is i start it and its on 5 cylinders until i drive up the road and load it up in second gear , then it seems to clear up and runs perfect.. except for it usual jerkiness on very light throttles which i assume is the camshafts or maybe tailshaft slop..

So what could it be that clears up with some load applied, could injectors be need8ng cleaned after 10k and using ethanol? Diesnt ethanol clean shit???

Tuners explains it as it must be dirty injectors but after he put shit plugs in not sure if hes right...

Coolant is not going down and fuel economy is good, power is good, its just cold start on 5cylinders till loaded up.

Edited by AngryRB

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • soviet_merlin
      Stagea Front CV Axle Question

      By soviet_merlin · Posted

      Man, different parts but the same numbers is terrible @dbm7! And it doesn't help that most online shops don't list the part numbers at all. They just give a list of compatible models...
    • MBS206
      R32 GTST - 600KW+ RB28/CD009 Build

      By MBS206 · Posted

      Slow when hot could also be because its getting more dynamic compression, OR things are getting a bit tighter once it is all expanded. If it were an earthing issue, typically I'd expect you to have it have issues all the time. Unless it's really a combination of both things. Where the higher compression, and things being a bit tighter, is giving that bit of extra load and you do need a slight clean up on the cables/connections.
    • dbm7
      Stagea Front CV Axle Question

      By dbm7 · Posted

      Yeah, this is one of the most annoying things about nissan part numbers... I've got an unrelated example... Image is of the AT output shaft ~ they have the same part#, but clearly the shaft on the left is beefier design to that on the right ...the difference (essentially) is the 'lighter' shaft on the right, is for engines up to RB25DE (this includes RB20 variants) : the shaft on the left is for RB25/26DET(T)....are they interchangeable? Yes...but obviously one shaft is going to be stronger than the other...and, the lighter shaft is around USD115, but the heavier shaft closer to USD150...same part#... ...epc-data usually tells a tale ~ the amayama listing for 39100-23U60 has a note "Longest side is between 60 and 105 cm" ; no such info is there for 39100-23U70 ...and given the great disparity in price between the 2 parts, it makes me at least curious (to the point of caution) where the 'extra money' went? ...ie; these 2 parts have a cost difference that (to myself at least) isn't explained by 'plastic boot'...ie; with amayama there's AUD700 price difference ...plastic versus rubber?...I'm not seeing it like that...and 60cm ~ 105cm...??...that's a huge disparity....something hinky going on here... I'd try searching by VIN, not model... /2cents
    • Duncan
      Stagea Front CV Axle Question

      By Duncan · Posted

      I don't know for sure, but I'd expect them all to be interchangeable given the diff end and hub end don't move/change between any C34 series. Often Nissan will change part numbers and the aftermarket follows those year ranges; but the original part number change doesn't mean other parts won't fit. The change could be a change in material, internal parts or even just supplier. For example, all the RB gearbox to engine bolts are no longer available and there is a new part number instead. The only change is they went from cadmium plated bolts to zinc plated due to the issues manufacturing with Cadmium. They look different but work the same.
    • soviet_merlin
      Stagea Front CV Axle Question

      By soviet_merlin · Posted

      One year is a bit concerning. Did you try contacting GSP? It says 5 year warranty on the box if I remember correctly. I'm also running their driveshafts on my S2 Stagea.   You could check the part numbers on Amayama for your year. Here's the link for my 1998 which gives the 39100-23U60 part number. Well, that and 39100-23U70. https://www.amayama.com/en/genuine-catalogs/epc/nissan-japan/stagea/wgnc34/6649-rb25det/trans/391 What does it say for yours?
×
×
  • Create New...