Jump to content
SAU Community

Recommended Posts

Skyline went to the mechanics 4 months ago. Prior to this the car had been off the road for about a year and a half. Got the car back from the mechanics after a major service (timing belt, bearings, water pump, head gasket, rocker cover gasket and the battery were replaced) and started having a similar issue with the engine surging at low rpm/rough roads.

Resoldered the AFM contacts which solved the problem up until 3 weeks ago when the same kind of issue returned. Took it back to the mechanic and he advised no AFM error codes were showing and it may be the fuel pump on its way out.

Last Sunday I replaced the fuel pump with a Walbro intank pump (GSS 341) and it stopped the surging for a day. This morning it came back. I am really at a loss at what is causing the issue but I am starting to think its electrical.

I am going to check the coilpacks for cracks and the wiring loom going under the right-hand side wheel arch this weekend. Until then - can anyone possibly think of some other areas to check that I am missing?

Cheers.

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/
Share on other sites

Can you define "surging" in detail? in terms of your car's behavior when this happens.

Revs range from 500rpm > 2000rpm. If I keep my foot stationary on the accelerator the revs jump up and down quite quickly - the car sometimes accelerates when it happens. You can hear the engine note increasing/decreasing and the turbo sounds like its still spooling. The issue only seems to rectify itself after I pull over and restart the engine.

I've tried to accelerate out of it but the issue either continues or the engine stalls. No mods apart from an Apexi pod filter and the Walbro pump. Engine is idling at 600rpm is this normal?

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5355650
Share on other sites

Check;

ECU for fault codes (Potential CAS issue)

Coil packs for cracks (Could just duck tape them to test initially)

Spark plug condition & gap

Failing that put a FP gauge onto the rail and check what your getting against factory values.

If the AFM was bad previously, it may have fouled the plugs due to running in safe mode.

Edited by James_03
Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5355661
Share on other sites

Check;

ECU for fault codes (Potential CAS issue)

Coil packs for cracks (Could just duck tape them to test initially)

Spark plug condition & gap

Failing that put a FP gauge onto the rail and check what your getting against factory values.

If the AFM was bad previously, it may have fouled the plugs due to running in safe mode.

Just bought a Consult cable so should be able to check for ECU fault codes alot easier on the weekend.

I was going to tape the coil packs after inspection as well. As for plugs NGK bcp6res should do the trick yes?

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5355978
Share on other sites

Just bought a Consult cable so should be able to check for ECU fault codes alot easier on the weekend.

I was going to tape the coil packs after inspection as well. As for plugs NGK bcp6res should do the trick yes?

yep, gap them to .8mm and youll be all good

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5355996
Share on other sites

aftermarket pumps arent supposed to work properly without a simple modification to the fuel pump wiring, i know the r32s had this from factory and i assume r33 would be the same. when engine is under load the fuel pump receives 12v but under low load conditions (idle, low throttle conditions etc) the pump will only receive 6v as full pressure isnt needed. the stock pump is designed to handle 6v obviously. aftermarket pumps usually aren't, and when u run this system through them they do all sorts of wierd things. i found this out when i upgraded mine to a walbro pump and it did not like this at all. it would start and idle fine, but the moment u give it some gas it would cough and splutter and miss all over the place. it was driveable, but trying to accelerate was a painful procedure.

the workshop who fixed it for me showed me a little grey box that they removed to fix it, located near the turbo. this little box is what switches the output voltage to the fuel pump. from memory they essentially just joined the 2 wires that went into it and the fix was as simple as that. from then on it received a consistent 12v, problem solved.

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5356007
Share on other sites

Revs range from 500rpm > 2000rpm. If I keep my foot stationary on the accelerator the revs jump up and down quite quickly - the car sometimes accelerates when it happens. You can hear the engine note increasing/decreasing and the turbo sounds like its still spooling. The issue only seems to rectify itself after I pull over and restart the engine.

I've tried to accelerate out of it but the issue either continues or the engine stalls. No mods apart from an Apexi pod filter and the Walbro pump. Engine is idling at 600rpm is this normal?

This sounds like a throttle position sensor or AFM issue. But more towards throttle position sensor.

Or unless if you have a really really dirty fuel tank. Which dirt clogs up the pump or fuel filter casing inconsistent fuel pressure. You fuel pump would sound very loud when that happens.

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5356043
Share on other sites

This sounds like a throttle position sensor or AFM issue. But more towards throttle position sensor.

Or unless if you have a really really dirty fuel tank. Which dirt clogs up the pump or fuel filter casing inconsistent fuel pressure. You fuel pump would sound very loud when that happens.

Mechanic did say that because the car sat idle for 1-2 years that a whole lot of sticky residue looked like it was in the fuel tank (he replaced the fuel filter that same visit). I replaced the stock pump with the Walbro to see if the residue had gummed up the pump. But alas - No change. I suppose that the only way to clean the tank is to drop it from the car?

Edited by Logikal
Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5356092
Share on other sites

Wife just took the car for a quick test drive (long time car enthusiast) and said that she was getting the same issue going up a hill so she turned on "Snow" on the A/T and it seemed to reduce the severity of the surging. It also misfired whilst she was reversing slowly.

Problems seem to be getting worse :)

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5356167
Share on other sites

Well hooked up the CONSULT cable and ran ECUTalk and a couple of other programs.

O2 Sensor voltage seemed to be jumping about between 0.00 to 1.00 - Is this normal? When I turned the car over (Has not been turned on since Wed last week) it ran rough as guts and a strong exhaust fuel smell was present. Is there any parameter I need to watch specifically or would a log of my car running from ECUTalk be enough?

Edited by Logikal
Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5363545
Share on other sites

Ok - Well that's good. As I an a complete novice when it comes to tuning, when changing the fuel pump is it advisable to change plugs / re-tune the ecu? The exhaust Also seems to smell of unburnt petrol. Is it running rich perhaps?

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5364684
Share on other sites

  • 4 weeks later...

I am going to clean the AAC valve tonight - will report on that tomorrow.

When I took the spark plugs out, I matched them to a thread on spark plug condition here and they ended up in the rich fuel/faulty ignition system category (hence why I taped the coil packs to see if that helped). One of the old plugs also emitted a noticeably stronger oil/fuel smell compared to the others.

I don't know if this is valuable info - but after the changing the plugs, reconnecting battery - I took it for a drive. Car started up and idled better than before. Took it for a test drive (30-40mins in both 60km/h and 100km/h zones) no issues and revs were stable. Took it for a drive last night - seemed to run a tad more rough than the test drive before but still had stable revs. Which brings us to this morning when the engine started to drop off and come back by itself nigh 5mins after driving the car.

It just seems every time I disconnect the battery/drain ECU it comes back nice for a short time then goes to the crappers again. I guess in the interim I will schedule a fuel system check/clean with someone. Any recommendations for workshops on the Sunshine Coast?

Link to comment
https://www.sau.com.au/forums/topic/329605-r33-surging/#findComment-5411581
Share on other sites

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


  • Similar Content

  • Latest Posts

    • Is anyone running these axles? R32, R33, R34 GTR front Axles. shafts itself rated 950hp. Suit all RB26 engines Croydon, Melbourne, Victoria Would be nice to pay half the cost of Driveshaft Shop Axles. I'm building an AWD S13 Coupe that is very low ride height (high cv angle) compared to stock R32. Has an RB30 with appx 600whp. Just looking for feedback. Thanks, Josh- https://www.instagram.com/feng_shui_garage/
    • Been a long time since r31 got some love, my brother dropped a shitbox ls1 crapadore in my lap to fix up.  Put a wiper motor in as the flooded one was no longer alive.  got windscreen wipers now. Time to clean respray and install back in the titanic  IMG_0505.mov
    • Nah its a server spammer thing  Although, now that I manually approve all the accounts I can probably loosen up some of the restrictions.  
    • Thread bump, again! Although, no bad news this time. Posting for the sake of possible root cause. Basically, I rebuilt it (mostly stock), installed Haltech + sensors, had it running fine on new ECU.  Still not really understanding why it cracked pistons last time. Got to tuners, and while checking timing, noticed +-10deg of timing scatter while revving. Changed CAS, and it was rock solid. While not definitive, can't imagine seeing 20+ psi with that amount of scatter would be a good thing. Also glad I found something.   Bit more of a run down; Carried out a stock rebuild, a set of stock pistons, out of a spare bottom end. Everything stock apart from head studs and oil restrictors. (so I can pretend I didn't let the Nissan out, ha.) Armed with the measuring gear and FSM, set about doing overhaul. Oil restrictors as per oil control thread for a RB25, stock oil pump, drifting. Head drain/vent from rear of head, to passenger side of sump above oil level. Two dash 10 vent lines from drivers side of sump (unused atm) Hi octane style cam cover breather kit Splash covers over last 2 cam caps. Both breather lines from cam covers to vented to atmosphere catch can, not plumbed back into sump (wanted to see what it was actually breathing). Got it run in (did about a 1000km) no to low boost scenario, As I had questions over old ECU setup. Installed haltech +sensors for flex Retune on E85 (finding CAS Issue along the way), made 300rwkw at 20psi, out of wastegate. Did a drift day the next day (yes, it was a big weekend!) and was checking catch can throughout the day, ZERO blowby. I mean nothing. Lines from cam covers are not even wet. Done a bunch of street driving, spirited and catch can is still dry. Early days I guess, but pretty happy so far. Also now run 10w60, up from the 10w40 that I used to run. Oil pressure is significantly better, especially when hot (as you would expect)      
×
×
  • Create New...