Jump to content
SAU Community

Recommended Posts

I have read the thread talking about a small flat spot and I have a similar problem but on a larger scale!

When the engine is under any kind of load the car flat spots like crazy! The first thing i tried was to change the plugs but that did not work, so the next thing for me to do is check the coil packs...

I was wondering about the best way the single out faulty ones in the set? Or if any body else has any idea as to what this might be!

NOTE: I dont think it is the fuel maps ( Flats spots a way to big)

& I dont think it is the cam timming ( had someone have a look at it)

Any comments would be helpfull, thanks guys....

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/
Share on other sites

Mate, this is true, i had exactly the same problem, its all fuel, when you turn the boost up, it dumps more fuel in, it needs to be leaned out. I had a slight miss on 7psi, (checked everything) then went to 10psi and it was useless. Everytime i booted it, and as it revved, it coughed , farted, backfired. You should see my dyno graph.

Put an SAFC in and it has done wonders, and so much more power.

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-511706
Share on other sites

Fuelling issue.. could be your fuel pump is dying. Get that checked out.. or at least the pressure in your fuel system is at the correct pressure under load.

Apparently to test the fuel pump squeeze the fuel line before it enters the rail. If the engine cuts out with only a little finger pressure its on its way out.

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-511790
Share on other sites

this happened to me when my 32 came back from the 'mechanics'...

Check your intake plumbing. Make sure a hose hasn't come loose at all, and that all the clamps are doing their job. Basically as my 32 hit 7+lb it would overfuel like a bitch and drown the engine. the more boost, the slower it went.

Just my 2c but good luck...

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-520376
Share on other sites

All though fuel is a problem in r33's because of the fuel dump at 4500 rpm due to the ecu ajusting for the duel stage stock boost controller, I dont think this is the source of the multiple flatting...

I say this because my car ran fine ( with a small flat at 4500) for about 3.5 months. Then all of a sudden the super flatting started!

This leads me to think that the problem is one of the following:

(thanks to all the posts above!)

1)AFM

2)coil pack

3)ignition pack

4)spark plugs & gap ( not the case because i have changed them over twise)

5)fuel pump and or filter

6)timming (long shot!!!)

Thanks again to all who helped with suggestions!!!

Any other suggestions will allways be helpfull.

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-521411
Share on other sites

I had the same problem with multiple flatting at higher than standard boost. Mine was fixed by putting colder plugs in. I know you've checked the plugs and assuming you put the same plugs in as the original ones you had, then this probably won't help. But I do know how frustrating it is trying to track the problem so I thought I'd mention it.

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-522678
Share on other sites

Yea, its very frustrating and I think everybody who tunes there skyline past stock probably goes through the same thing!

I was running shit sparkies which led me to think that they were the weak spot. But I now run NGK Iridium's and i was under the impression that these are quiet good, am i on the right track here?

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-522686
Share on other sites

I'll start by letting you know I'm an accountant, not a mechanic, but Iridiums are supposed to be very good.

I had platinums put in mine when I bought the car and had this flat spotting problem when I increased the boost. It would get worse if I gave the car a hard time (engine gets hotter).

Plugs have a heat rating and I think spark at a different temperature depending on their rating. When I replaced the plugs with colder ones, the flat spotting went away.

Perhaps get a second opinion though as I don't want to give you the bum steer. Plugs aren't cheap.

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-522697
Share on other sites

Its not spark, me think its still fuel, i changed plugs and it didnt do anything. As soon as i upped the boost, it got worse so i would to run stock boost, even then it wasnt good as it got warmer.

Get an SAFC, lean the fuel out. When you increase boost more fuel is dumped in, simple.

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-522827
Share on other sites

fuel is the easy one to check - get a $40 power run done at ur local dyno and check the AF curve.

its spark which can be a prick to find, and you never know it could just be a dodgey connection somewhere in the ignition wiring, these cars are getting on 10 years old now and with intense heat its easy for connections to corrode

Link to comment
https://www.sau.com.au/forums/topic/23922-savage-flat-spots/#findComment-523659
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

    • So the clockspring is responsible for the indicators cancelling on their own? I thought that was the function of that green thing in the center (any idea what it's called?)
    • Can you log IAT? Whilst WTA coolers have their place, doing any sort of sustained run is not one of them There are fixes that slow down the heat soak, like ice boxes, which don't last that long, and interchillers, which are fairly expensive, up grades to the WTA cooling radiator, which may require a bigger pump, and upgrades to the reservoir size,  and upgrades to the cooling fans, but, it all still heat soaks, and takes ages to come down in hot weather  For a turbo, that isn't locked into WTA like my PD blower is, can you not possibly swap to a nice air to air intercooler????, it would be better for sustained runs then, and have alot less things that could go wrong in my opinion 
    • So, the other thing I've sorted is a baseline dyno run up at Unigroup's new location. The auto trans was a little unco-operative by both shifting down when the throttle was floored on the dyno (so Mark had to ramp it up more slowly than in a manual) and also by shifting up at 6,000 even in sports mode instead of the indicated redline of 7,000 Still, on a hot day it made 240rwkw at 16psi which seems about right for 300kw (400hp) through an auto at the wheels.  The shape of the curve is not quite right because it was not full throttle to about 4,500 to stop it kicking down, but until I can get a tune on the auto trans control this was the best we could do.....full boost will be well below 5,000 once that is sorted, I'll get some data logs when I can to confirm For comparison, the R32 made 255 at 12psi (at 4,500) on the same dyno with tune, n1 turbos, cam gears, big exhaust but otherwise all standard so the v37 is likely a little better out of the box. One thing that is very clear is that the standard water to air intercoolers are not up to sustained use at full throttle in warm ambient temps. After about 5 runs (so only a few minutes full throttle), it was pulling boost and timing and dropping 10-15% power. Unfortunately I didn't get that printout and the Unigroup guys are away at the moment, will try and get hold of it on their return. So, looks like a healthy engine to start modifying and the only real area of concern is the w2a heat exchangers which the aftermarket has plenty of solutions for    
    • I maintain it actually looked really nice in person. So much so that I thought "No, this is illegal" but there it was, clear as day. I think we can easily call the wing and wheels/height to be transformative. Not saying it's better than the GR Whatever, or the 86, or the WRX STI or anything of that sort (the internet says it all bolts up so you can buy best of all worlds?) but it's still at least a thing and not nearly AS bad as people say.
    • That's less offensive than the previous gen.....except for all that ugly black tupperware around the edges. Blerck!
×
×
  • Create New...