Jump to content
SAU Community

Stuttering/hesitant At High Revs

JamesK

By JamesK,
in Victoria

 Share

Recommended Posts

JamesK Experienced

JamesK

Posted
Posted

Hey guys i started to notice recently when i drive flat out and at high revs the car stuttered/hesitated a little i thought it was the sparks so i change the shitty ones that were in there to nice new NGK iridiums :/ it didnt fix it per say but the problems changed now it feels like im hitting the rev limiter at 4-4.5K for a moment then goes fine again, but i havent been able to get on the freeway to really give it a go yet. Im thinking it might be the packs but i wanted to get some input before i blow a wad on splitfires, also could it be the fuel pump? Maybe ill change the fuel filter and see how that goes first

Link to comment
https://www.sau.com.au/forums/topic/318677-stutteringhesitant-at-high-revs/
Share on other sites
ashneel Grand Master

ashneel

Posted
Posted

coilpacks.

easy way to check is take out all coilpacks and give them a good clean. look carefully for hairline crack. usually looks like white powdery cracks. if you see then that means your coilpacks are gone. if you can do a DIY repair on them with some clean silicone sealant.

i did that to my R34 and it handled 240rwkw daily for over a year and still going strong.

JamesK Experienced

JamesK

Posted
  • Author
Posted
coilpacks.

easy way to check is take out all coilpacks and give them a good clean. look carefully for hairline crack. usually looks like white powdery cracks. if you see then that means your coilpacks are gone. if you can do a DIY repair on them with some clean silicone sealant.

i did that to my R34 and it handled 240rwkw daily for over a year and still going strong.

Hmmm that might make sense, I noticed on the 4th sparky that it was the only one covered in a small amount of white powder, I was wondering what it was but I was in a bit of a rush to get them back in so I didn't take much notice. Do you think that's the problem?....splitfires time?

ashneel Grand Master

ashneel

Posted
Posted

well it could be that or anything really. thats just the first and easiest thing to check. and if faulty cheapest to fix. try the DIY method out first or borrow somones coil packs. then if that fixes the problem you can make you mind if you should get splitfires or not.

JamesK Experienced

JamesK

Posted
  • Author
Posted
well it could be that or anything really. thats just the first and easiest thing to check. and if faulty cheapest to fix. try the DIY method out first or borrow somones coil packs. then if that fixes the problem you can make you mind if you should get splitfires or not.

Just did the whole tape DYI fix, not sure, it seems like it reduced the symptom but I'm also thinking it could be placebo effect. I didn't see any cracks or anything on my packs though....

BeEnAr Experienced

BeEnAr

Posted
Posted

take it off and clean it. Get the MAF sensor cleaner from Bursons etc. it works a treat!

When you say you did the Tape DIY fix, wht did you tape? If it was the coils themselves then maybe do the whole loom as well, I did the loom on mine and it fixed all stuttering issues I had, after cleaning the MAF's and doing the solder joints on them too. Oh and make sure your spark plugs are gapped down to .8mm

JamesK Experienced

JamesK

Posted
  • Author
Posted
take it off and clean it. Get the MAF sensor cleaner from Bursons etc. it works a treat!

When you say you did the Tape DIY fix, wht did you tape? If it was the coils themselves then maybe do the whole loom as well, I did the loom on mine and it fixed all stuttering issues I had, after cleaning the MAF's and doing the solder joints on them too. Oh and make sure your spark plugs are gapped down to .8mm

mmm might have to have a look into that, I only taped up the actual packs and not the rubber part if thats what you mean. I was thinking about the gap. I thought it was 1.1 for stock boost?

BeEnAr Experienced

BeEnAr

Posted
Posted

nooo not the packs themselves, you don't need to tape them up. Pull the loom off (the wires with all the plugs) and check it for any splits, (mine had several and could see bare wire on a couple) then tape the whole thing up with some decent electrical tape (nitto FTW) then you should be right, if that's your problem

JamesK Experienced

JamesK

Posted
  • Author
Posted
nooo not the packs themselves, you don't need to tape them up. Pull the loom off (the wires with all the plugs) and check it for any splits, (mine had several and could see bare wire on a couple) then tape the whole thing up with some decent electrical tape (nitto FTW) then you should be right, if that's your problem

I just followed this guide

BeEnAr Experienced

BeEnAr

Posted
Posted

yes, but dit you have any cracks in the epoxy or not? If no then you wasted your time. Try doing the loom as well, you'll probably find it has a split somewhere, otherwise I rekon it's dry solder joints in the MAF Sensor. Fix it by resoldering the joints Tutorial Here

JamesK Experienced

JamesK

Posted
  • Author
Posted
As far as I know James is still running the standard boost solenoid so boost cut is out. I still place my bet on coilpacks.

Kirs is right standard boost :(, gonna order new splitfires I think

BeEnAr Experienced

BeEnAr

Posted
Posted

Have you checked your Loom and done the MAF joint with fresh solder yet? That's a LOT cheaper than new Splitfires. If it's not your coils then when you get your new ones you will have the same problem.

The above 2 fixes will take bugger all time to do and will cost you all of $5 for tape and solder a little more if you need to buy a soldering iron too but still a lot less than the Splitfires will sting you :)

Owgasm Grand Master

Owgasm

Posted
Posted

I had this problem after a quick squirt on the track.

Checked everything, sparks, coils, intercooler piping etc.

Turned out to be the Vac hose on the Fuel Pressure Regulator, felt kinda stupid once I noticed the little hose dangling.

Chances are yours isn't this, but yeah.

Good luck.

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

    • MBS206
      S1 rb25/s14 starting problem

      By MBS206 · Posted

      Check the injectors flow evenly, and are actually flowing what you and the ECU think they should be flowing. If it's starting up on starter fluid, you have a fuel issue. Is it possible under cranking your fuel pump is turning off?   The harness you replaced, is that the whole engine harness? Do yourself a test, and drop the old harness on and plug it into the Z32 ECU. It's possible they've wired things different. From memory S1 to S2 is different in RB25 and you may have a wrong loom
    • 25zenki
      S1 rb25/s14 starting problem

      By 25zenki · Posted

      I haven’t pulled the injectors to watch them spray yet but they are clicking from the cas and all of the spark plugs are wet with fuel. I’ve thought the cylinders were being flooded from the beginning and was hoping fuel pressure would fix it. Tonight I am going to pull the rail and watch the injectors spray. Don’t know how to test/diagnose if the plugs are firing in correct sequence but that should be a timing thing and as far as timing goes my car still has the half moon for the cas can only install it 1 way. And my mechanical timing is 100% correct I posted photos above. Confirmed with the balancer on and off. 
    • 25zenki
      S1 rb25/s14 starting problem

      By 25zenki · Posted

      I checked spark on all cylinders and they all visually have spark with the plug pulled and grounded, but plug 1 is the only one that fouled. This was a running swap that blew up and was rebuilt by a machine shop, put a new wiring specialties harness and did all gaskets, studs, and bolts while it was out.  compression is 135-150 across all cylinders. Aside from that from my understanding with the z32 ecu and maf the car should start regardless. The wiring for TPS and the dual 02 sensor/ dual knock sensor stuff shouldn’t actually stop the car from starting or even running well, (just slightly rich)  they just give fault codes. Car supposedly is supposed to start as long as you have z32 afm and ecu with the nistune base map and that’s info coming from a well known and trusted tuner who does a lot with SR/RB (Rsenthalpy). After more trouble shooting today where I’m at right now is that the cas is sending signal to the injectors they click while spinning the rotor, Fuel pressure is now set at 43psi, all cylinders have good compression and all of the plugs looked great (just wet with fuel) except for cylinder 1 which was very black (cylinder 1 has 150psi compression). all of the coils generate spark if pulled out and grounded out on the head. On the fuel pump car just pops into the exhaust. On starting fluid car will fire off. Hard to tell if all cylinders are firing off but definitley a couple. sounds like all of them but it’s only for 3-5 seconds hard to tell. 
    • DraftySquash
      Looking for someone with a R34 front bar

      By DraftySquash · Posted

      Final update!!! Got the front bar fitted and sprayed and all sorted now. My cutouts worked great and the indicators aren’t just falling off. 😂  
    • Dose Pipe Sutututu
      new 1.5 LSD issues/concerns

      By Dose Pipe Sutututu · Posted

      Is this a brand new LSD? if so, have you followed any break/bed in procedure for it? Usually involves heaps of figure 8 patterns, a fluid flush.
×
×
  • Create New...