R33 Gtst misfire and stalling..

[Morello_R33]

So recently picked up my 1st skyline, 2nd hand and as with 90% of second hand cars comes with problems..

After replacing a cracked radiator, flushing the system, replacing the thermostat and all 3 fan belts i have been getting a issue with misfire and stalling..

This problem was present when i got the car and originaly use to misfire under heavy load at 2500-4k rpm.. and i mean misfire... temporarily fixed the breather hose as it had a split and the auto shop needs to order one in.. with that misfire increased to 4000-5500 rpm range.

Still not sure what the cause is but getting works mechanic to look it over 2moro morning..

Other issue i am having is it has stalled a few times. Once 5min after i started it, driving in traffic.. next leaving for work stalled in the driveway just after startup.. 3 times its come close to stalling but self started..

this arvo after work was bad, stalled 3 times.. got it going and stalled again.  switched off the turbo timer as it was beeping and its fine since.. currently waiting to pick up the other half from the station meaning car would have been sitting for 45min.. see what happens next.

 

Seems to be a common problem if anyone has any tips.

[Morello_R33]

only misfires in gear.. neutral or park i can red line it without any misfire..

[KiwiRS4T]

No 1 tip - get rid of the turbo timer.

Common cause of missing - if plugs look new gap them down to 0.8mm - if not get new ones and gap them down to 0.8mm.

Do the coils look stock? If they look old give them a very good clean and spray or wrap with insulation. You might be able to see on the coil body if it has been shorting. Otherwise replace with new OEM or Splitfire coils.

Those are the basics - there are lots more things you could look at. Google your question. You will get lots of suggestions.

[GTR-32U]

tell me more about the car. Does it run the standard blow off valve or aftermarket venting to atmosphere ? How standard is the car ? Standard Ecu or aftermarket and tuned..? The more info you provide the quicker and easier to find the gremlins

 

[Morello_R33]

havent had a chance to get into the guts of it..
Most of the components are stock as far as i know (aftermarket pod filter + exhaust) typical mod..  BOV is stock from what i can tell, not venting to atmosphere.. ECU not sure, actually googling where its hidden now

unfortunatly the guy i got it off wasnt "extremely helpful".. said he'd owned the car for the last 6 years, and had not modified it himself.. he wasnt sure what was done other than the pod and exhaust and turbo timer

[Morello_R33]

the rain today seams to be making it worse... (Mt Druitt area)

[GTR-32U]

Yep I understand exactly what your going through. I'm going through the same experience myself. That's half the thing about buying an import......Fixing somebody elses stuff ups. Stick with it, You seem to have the right attitude. With persistence and the process of elimination you will succeed. aac valve could possibly be worth a look in as well

[Morello_R33]

will definitely check it out.. got works mechanic to look at it first thing, will post any findings.  Could help others d('.')

[Morello_R33]

Hmmm... so not raining like yesterday but still wet as a result... turned the turbo timer off and coincidence or not,didn't misfire or die on me... ill still take it over to the mechanic to look over and see what happens..

[Morello_R33]

if the GTR is the king, then the runner up (GTST) is definitely the queen, and like any women.. can be temperamental..
NO issues this morning driving to from work, no issues at the mechanics.. went out for dinner and it was playing up on the way back  ???

[tridentt150v]

Not playing up with lights on vs lights off is it?

[samak91]

Could be ur fuel pump thats about to die or shitty injectors fuel contamination the list goes on [emoji21]

[Morello_R33]

Quote

 

Tridentt150v.. nope, very intermittent..

[Morello_R33]

Thats one problem down..
Changed the spark plugs over, 2 were covered in lime scale and had rust on them (99% sure this was my intermittent misfire).  The rest, swapped out and replaced anyway, no obvious issues with those plugs, and appeared to have a good burn coating.  New plugs have been gaped to .8 as suggested and yeah... no more misfire (*touch wood*)
Since tho, i had the car stall 5 time in concession whilst at idle.. I had started the car up, warming it before i left visiting family and whilst at idle it stalled around a min after i started it.  Complete shut off..  As i said, this happened 5 times in a row before i drove off.
Also noticed both the interior lights, and headlights dim/brighten with higher/lower RPM.  New alternator, new belt.. going to check it over with voltage guage today.

Now stalling issue.  Im thinking, Probably fuel pressure, either the pump on its way out, clogged/dirty fuel filter, or faulty pressure regulator.  When it stalls, it just dies.. no coughing or spluttering

[Morello_R33]

Edited September 3, 2016 by Morello_R33

[Morello_R33]

other plugs are lightly browned/tanned..

 

Edited September 3, 2016 by Morello_R33

[turb33gtst]

If you ever think your coils are part of your problem you can check this by wrapping a good quality insulation tape around coils about 3 layers should be sufficient

If problem then improves I would say you could have bad coils and should be replaced as well. 

[Morello_R33]

coils are good, the plugs were the culprit to the misfire issue..
On another note, my mechanic said that the exhaust manifold has a leak.  cant pinpoint if its a crack in the manifold or the gasket without pulling it apart, but seams to think that "that could be why you are stalling, due to back pressure loss.."
On a GTST, is that possible.. asking cause ive run a VS commodore without the exhaust before (for shits n giggles).. i didnt run it long because it was LOUD! but the car didnt seam to be bothered by that.
Is a manifold leak a possible culprit to stalling?

[Morello_R33]

Reading around, some of the culprits that have been raised are
1) AAC valve
2) Ignition Module.
3) Crankshaft Position Sensor.
4) MAF sensor.

I dont have any misfiring, or coughing from lack of fuel (if anything im running rich 230km on 3/4 tank) and when the car stalls it acts as if ive just turned the car off. Dash is still up and i have HICAS light on (no faults) and Engine Check up (Still need codes checked).
Stock recirculated BOV, new plugs, coils *a-ok*. New fuel filter.

[Morello_R33]

I may have fixed it  *touch wood*
stumbled across a forum post and it was suggested to look at the connection for the AFS.  looked into mine and whilst it wasnt damaged it had the SMALLEST bit of rust and 1 of the pins was a few mil out of alignment to the other 2. cleaned them up, realigned them and so far so good.. (fingers crossed)