Jump to content
SAU Community

R32 Gtst Sputtering/ Missing Under Boost

jj_syed

By jj_syed,
in General Maintenance

 Share

Recommended Posts

jj_syed Explorer

jj_syed

Posted
Posted

Hey guys, cheers from Calgary, Canada! its my first post on this site so go easy on me :) I have a 92 gtst with the standard rb20det. to keep the long story short it misses in high rpms ONLY under boost.

I have pretty much tried everything, taken it to many places yet no solution. When i first got the car 2 years ago the throttle was very jumpy and overly sensitive. So that turned out to be my tps being set at 0.11 and Cas was turned completely CWW. And that time it was running fine but felt like there was no top end power after 5k. After the tps adjustment and CAS being set at 15. Car feels like it has more power up until u hit 4k it just sputters and bogs.

However if u just tap the gas and wait for the rpms to climb slowly it does it with no hesitation.

Here is the list of things I have done so far:

-changed the plugs to ngks irridiums last september gapped at 0.8mm (re chaecked them and they are still ok)

-Changed fuel filter and fuel pump with walbro 255

-cleaned maf with sensor clean (helped with response but problem still there)

-Octane booster, seafoam

-set tps at 0.46v ( made the the car idle at 1200 rpm.....)

-checked coil packs, visually they seem to be fine

Any suggestions??????

Thanks

jj_syed Explorer

jj_syed

Posted
  • Author
Posted

I use 94 octane thats the highest octane we can get here :(

I will be trying to tape up my coils and recheck them. I hear just using a multimeter isnt enough to tell whether they are bad or not!

I will also try using some copper core and re gap them for to test and see if it helps.

Keep u guys informed thanks for the replies!!!!

jj_syed Explorer

jj_syed

Posted
  • Author
Posted

I have noticed another thing recently too, seems to miss in lower rpms a bit when the engine is fully warmed up after like 20 mins of driving.....could that definately be my coils then?

Truffles Community Regular

Truffles

Posted
Posted

I use 94 octane thats the highest octane we can get here :(

I will be trying to tape up my coils and recheck them. I hear just using a multimeter isnt enough to tell whether they are bad or not!

I will also try using some copper core and re gap them for to test and see if it helps.

Keep u guys informed thanks for the replies!!!!

That could also be your problem. Over here, we generally run ours on 98 octane.

get copper plugs and regap to 7mm then try it. If the problem persists then use quality electrical tape to insulate around the block part of the coilpack. Or even better, use a heat resistant silicon in the crack on the block part. There was a thread about the silicon but I can't find it.

boiracer Grand Master

boiracer

Posted
Posted (edited)

tape and silicone worked a treat on mine. but mine had the stutter only when cold in winter when you hit it getting onto a highway.

any basic silicone will stand more than enough heat for where the coil packs sit. smear a bit on each coil, wrap em up with good electrical tape and your off (if of coarse this is the problem)

Edited by boiracer
jj_syed Explorer

jj_syed

Posted
  • Author
Posted

I will be using silicone tomorrow and retape the boots and see if that solves the problem. I also read that if u relocate the ignitor that sits on top of the plug cover helps because that tends to overheat and fail, has anyone tried yet?

jj_syed Explorer

jj_syed

Posted
  • Author
Posted

ITS FIXXEDDDDDDDDDDDDDDDDDDDDDDDDD :):worship::banana:

changed the plugs to copper cores gapped at 0.8mm and siliconed the base of coils, taped the rubber boots on the coil packs.

it purs in high rpms!!! i havent hit 6k on this car in sooooo long!!!!

THANKSSSS GUYS i hope this helps others with similar problems

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

    • Erelyes
      Ceramic turbine damage to engine - what did yours do?

      By Erelyes · Posted

      Ha, well, it's been.... a bit of a journey. Things have taken much longer than I'd hoped. I'll probably put up a thread at some stage. Hopefully soon. The car's not done any kms since my update in June though, put it that way.
    • Dose Pipe Sutututu
      M35 Aftermarket Fuel Pump

      By Dose Pipe Sutututu · Posted

      Here's the chart for fuel pressure vs. current draw, assuming your base fuel pressure is 3 bar and you run like 0.5bar boost on WOT, you should only momentarily hit 9amps here and there. (Ignore my prev post, I cannot read a chart these days it seems)
    • GTSBoy
      RB25 Drama's

      By GTSBoy · Posted

      Those comp test results are not hideous. Whether they are accurate or not (ie, when that comp tester says 140 psi, is the real pressure120, 140 or 160?) is unknown to us. The state of the battery used to crank it over is unknown, etc etc. Many people around here would say that the absolute values and the spread are perfectly fine to just add boost and keep going. I personally would be happier with a narrower spread than that, but even the diff between 125 and 145 is not terrible. That one cylinder at 125 though, has probably copped some damage relative to the others. You should inspect the valves seeing as you've got it open. Do you know how to measure installed ring gaps? That, and an inspection of the rings themselves, is how you will determine whether they need to be replaced. If you're not good to do these things, take the block and the pistons and rings to a shop that is, and ask them for the go/no-go on them. Do the bores need a hone at all? If so, you might well be justified in getting some different pistons in order to get away from the ring supply problem. Whether you're happy to spend a lot more money right now, on more gear, rather than less money, but an amount that looks stupid given that you will only get a handful of rings in exchange for that money, is for you to decide.
    • iain_ST44GA
      M35 Aftermarket Fuel Pump

      By iain_ST44GA · Posted

      also possibly backed up to my filler and shat down it! 🤣
    • Julsmadrid
      RB25 Drama's

      By Julsmadrid · Posted

      Ok so i would love some advice here please, i purchased an R33 a few months back and its had a few mods done to the engine, its an RB25det running a Master ECU, 1200cc injectors, bigger turbo, oil cooler, oil filter relocation kit, Spool H-beam rods, acl/ross pistons. When i removed the motor from the vehicle (as its getting a respray) i thought i would compression test it and these are the following results. Cylinder 1-145psi, Cylinder 2-143psi, Cylinder 3-125psi, Cylinder 4-145psi, Cylinder 5-140psi, Cylinder 6-135psi this test was done with the motor on the ground and powering up the starter motor. I dropped the sump and found broken oil squirters on cylinder 3,5 and 6. I was told my rings are probably worn so i stripped the motor completely to get a new set of rings for it. The trouble is no one has these rings anywhere and they have to be custom made by Ross over in the states and will cost about $600+$200 delivery. My question is how can i tell if my rings are at fault and if they are still ok and is this price ok for a set of rings?
×
×
  • Create New...