Jump to content
SAU Community

Recommended Posts

Hello all.

Tonight I went to take my Stag for a good run as I'm about to go away for a month.

When I put my foot down though things went pear shaped. It started what felt to me like it was missing a bit. The power wasn't smooth at all. And the exhaust was spluttering like it does when it changes gears if I'm fanging it.

I hope someone can understand what I'm talking about and tell me it's nothing major. I haven't checked anything yet as it's dark outside. Not real sure where to look either.

Sorry about the vagueness of ther message. Any help or info would be awesome.

Thanks guys.

Zane.

Link to comment
https://www.sau.com.au/forums/topic/61835-my-babys-playing-up/
Share on other sites

  • 1 month later...

Similar experience......ours started playing up a bit after the long run (400 k's straight). It would miss occasionally under load and drop a cylinder at idle sometimes. As usual, first guess would be plugs. It was my undertanding that it had new plugs put in during the compliance process, but I figured I might as well check them anyway.

The plugs sure looked new but they were Autolites, APP 3924-11's. Now I have never had much luck with Autolites, and 1.1 mm is way too big a gap. So in went a set of the usual NGK BCPR6ES's gapped to 0.8 mm. Bingo no miss, runs perfectly and I am sure makes more power.

I don't know whether anyone else has checked their plugs since compliance, but it might be worthwhile as both burkey22 and I have had similar problems.

:P

When I checked mine they were the factory ones (only had 57k). I didn't bother waiting for it to play up. I scored a set of Iridiums from a mate that used them for about 2 months for nothing ;) . Already gapped to .8mm in the right heat range too, and chucked them straight in :D

I had the spark plugs replaced - the originals were still in the car. Had injectors cleaned, transmission and diff oil replaced...

Car still misses and does strange things with the g box swapping gears while cruising and not changing down when cornering...

Apparently no cracks in the coils. Been told it might be air flow meter or fuel flow sensor thing - as the car does not exhibit the problems consistently, the auto electrician/mechanic couldn't find any faults, so have to wait until the car misbehaves consistently ;)

Just looked at the part number of plugs that were installed - NGK BKR5EIX-11 - now would these plugs have too large a gap and be too 'hot' for a standard stag engine with out mods apart from a panel filter?

Would the larger gap also make the car feel a little sluggish apart from the possibility of mis-firing? I am wondering whether the problems I am still experiencing with the odd running of my car is now also due to incorrect spark plugs... any comments?

:)

Just looked at the part number of plugs that were installed - NGK BKR5EIX-11 - now would these plugs have too large a gap and be too 'hot' for a standard stag engine with out mods apart from a panel filter?

Would the larger gap also make the car feel a little sluggish apart from the possibility of mis-firing? I am wondering whether the problems I am still experiencing with the odd running of my car is now also due to incorrect spark plugs... any comments?

:P

The -11 = 1.1 mm and from my experience that's too big, particularly at more than standard boost. I used 0.8mm on the NGK BCPR6ES, actually they came as -8, but I still checked the gaps. I use BCPR7ES in the race car, but they are too cold for lots of traffic driving. Hence the 6's are the go.

My suggestion would be to gap them down to 0.8mm, the heat range shouldn't cause the missfiring.:)

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

    • No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
    • God damnit. The only option I actually have in the software is the one that is screenshotted. I am glad that I at least got it right... for those two points. Would it actually change anything if I chose/used 80C and 120C as the two points instead? My brain wants to imagine the formula put into HPtuners would be the same equation, otherwise none of this makes sense to me, unless: 1) The formula you put into VCM Scanner/HPTuners is always linear 2) The two points/input pairs are only arbitrary to choose (as the documentation implies) IF the actual scaling of the sensor is linear. then 3) If the scaling is not linear, the two points you choose matter a great deal, because the formula will draw a line between those two points only.
    • Nah, that is hella wrong. If I do a simple linear between 150°C (0.407v) and 50°C (2.98v) I get the formula Temperature = -38.8651*voltage + 165.8181 It is perfectly correct at 50 and 150, but it is as much as 20° out in the region of 110°C, because the actual data is significantly non-linear there. It is no more than 4° out down at the lowest temperatures, but is is seriously shit almost everywhere. I cannot believe that the instruction is to do a 2 point linear fit. I would say the method I used previously would have to be better.
    • When I said "wiring diagram", I meant the car's wiring diagram. You need to understand how and when 12V appears on certain wires/terminals, when 0V is allowed to appear on certain wires/terminals (which is the difference between supply side switching, and earth side switching), for the way that the car is supposed to work without the immobiliser. Then you start looking for those voltages in the appropriate places at the appropriate times (ie, relay terminals, ECU terminals, fuel pump terminals, at different ignition switch positions, and at times such as "immediately after switching to ON" and "say, 5-10s after switching to ON". You will find that you are not getting what you need when and where you need it, and because you understand what you need and when, from working through the wiring diagram, you can then likely work out why you're not getting it. And that will lead you to the mess that has been made of the associated wires around the immobiliser. But seriously, there is no way that we will be able to find or lead you to the fault from here. You will have to do it at the car, because it will be something f**ked up, and there are a near infinite number of ways for it to be f**ked up. The wiring diagram will give you wire colours and pin numbers and so you can do continuity testing and voltage/time probing and start to work out what is right and what is wrong. I can only close my eyes and imagine a rat's nest of wiring under the dash. You can actually see and touch it.
×
×
  • Create New...