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Sup,

I've finally gotten around to finishing a ton of work, including my new -5's. But it's now a bitter sweet situation.

I started it up, not a problem, engine started first crank as though I drove it yesterday. Idled like a dream, not one issue, I was happy.

Then it developed a very minor misfire on idle. It had been idling for about 15 minutes by this stage, letting everything warm up to check for any leaks, etc. I kinda figured the fuel was crap by this stage, but still good enough to drive it away, since the misfire was minor. Big mistake which will cost the money I saved on some bargains.

Took it out, up the street, light throttle about 3000rpm then it started dying instantly. It was like a switch, engine off, engine on, engine off, engine on, in half second intervals. Obviously I turned around asap and took it home, where after it died coming into the driveway.

Since this happened I've drained the 40 or so litres from the car, it was a very orange/red colour (assumption: dead fuel) and I'm not really versed in the smell, but it didn't smell 'potent' like good fuel does. I drained it by hotwiring the pump and running till empty. I then put 10 litres of VPower in it, pumped it through the rails, then drained all of that as well. Then I pumped a full tank of brand new VPower. Still wouldn't start though.

So then I replaced the fuel filter, the old one felt quite blocked when I blew through it. With the new one installed, tried again, still wont start properly. - It stutters with the starter motor on occasion, sometimes it'd start running and misfire for 2 secs, then dies again but it's been doing this since the problem started.

Pulled the plugs out, all 6 spark fine off all 6 coils, but I replaced them anyways with new BCPR7ES's. It still wouldn't start.

Took the plugs out, and they are wet with fuel. I crank the engine without the plugs and I can see fuel run over the top of the pistons, all of them.

----

So whats going on here? The fuel works, the spark works.

The engine DID run fine, and slowly degraded, so I put electrical problems behind me.

The spark plugs all sparked fine, on all coils, so I ruled out ignition.

New air filters, def not blocked.

If the injectors (Enterprise 700cc, traveled 3000km) were blocked, I'd get no fuel?

Should I see fuel vapor coming out of the engine? Or fuel running over the top of the piston? (By run, I mean very minor, I see wetness appear and fade, not a tidal wave)

Could it be a possibility the injectors are hosing the engine?

Anyone know a reputable fuel injector cleaner on the Coast? I know of them, but I haven't used anyone before.

Anyone had experiences with this exact problem? I know some GTR's don't get driven often at all.

Excuse the thoroughness, just explaining everything step by step in case anyone else has had the exact same thing happen and know exactly what was fixed.

Cheers in advance as always.

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what exactly did u do to the car? all you have said is new turbos, did you install bigger injectors too ? by the sounds of it you have over fueled the engine big time and possibly glazed the cylinders

Car runs a power fc, z32 afm's etc. The afm's and injectors were installed at croydons and tuned from there. That was over a year ago. None of that was changed, just new turbos and dumps on the engine. (Car hasn't been driven at WOT with new turbos either for obvious reasons until tuned)

And to add, the car was running perfectly fine, after 15 mins of idle it started to play up.

Edited by GTRPowa
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what exactly did u do to the car? all you have said is new turbos, did you install bigger injectors too ? by the sounds of it you have over fueled the engine big time and possibly glazed the cylinders

It takes frickin AAAAAAAAGES to glaze bores with extra fuel when an engine is already run in. It's only fresh engine that this is a problem for.

Check to make sure you plugged the AFM's in and check that you plugged them into the correct ones.

Go into sensor check and make sure you get a reading from them as well

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Your air flow rates should show up on your hand controller, the only thing that won't will be the boost (unless you have the apexi add-on). This is just for the RB26's, RB25's don't show an airflow rate :)

Don't know wether or not I missed it, and it's now a moot point but, how long was the fuel sitting around for?

So at the moment, the starter motor cranks, but it just won't fire over? The only thing that I can think of that's not checking all your plugs and other crap like that is maybe the injector timing or tune was lost at some point, but highly unlikely.

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Do a sensor check through the FC as already mentioned.

Sounds like it was running without AFM's and consequently fouled the spark plugs. I am actually suprised that it didn't kick after you replaced the plugs.

Pull the feed line off the rail too and check your getting good pressure with the ign on.

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agree

a key sensor is toast, loose, faulty or being silly

check ETC SENSOR SW CHECK

stale fuel would just make it detonate on full load (engine light going spazzo)

it wouldnt make it start / stop / start like you described

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agree

a key sensor is toast, loose, faulty or being silly

check ETC SENSOR SW CHECK

stale fuel would just make it detonate on full load (engine light going spazzo)

it wouldnt make it start / stop / start like you described

^^^^ +1

Have started cars after 2 years of sitting and fuel was not a problem, not ideal, but not your cause

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Yeah the AFM's are plugged in, and I assume they are correct because the connectors don't reach the opposite AFM's. I didnt think it mattered which AFM was plugged into where, because it averages the both?

I was looking at sensor check when the car was actually running, both AFM's, O2's, TPS, etc etc were working. The Idle as well.

I spoke with a fuel injection guy this morning and he thinks it could be the ignition/ignitor. I'm going to test the length of the arc with a screwdriver as we speak. He also said with all the fuel dyes nowadays that my red fuel could have been just that, red fuel.

I will also review my Sensor Check again.

Any further tips appreciated.

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WTRT is pretty high

what does MONITOR, 1 CHANNEL, WATER TEMP show ?

Both water and air temp show 14 degrees C, my current ambient temperature.

I was thinking that this problem is indicative of the CAS on the way out. I've taken it off and done some measurements as per the manual, but I'm getting vague readings from it.

Eg, I'm supposed to get 12 volts on terminal 3 with IGN on, I always get this without a problem.

However terminals 1 and 2 are supposed to alternate between 0 and 5v? I expect nothing in between?

On terminal 1 I get 0.02 volts, earlier it would change to 0.07 volts when a gap in the CAS disc would pass the sensor (This is inside the CAS). Now It's always 0.02v no matter the angle of the CAS.

On terminal 2 i get fluctuating voltages from 0 to 5 and anything in between. Shaking the CAS makes the volt meter go all over the place, I see voltages such as 0.40, 2.68, 3.7, 4+ etc.

On top of all of this, when I turn the sensor with the PFC on, I should see the engine rpm going up? When I crank the engine with the CAS installed I should also see the RPM going up? And again, when cranking I should see my tach needle go up a tad? None of this happens.

However once of twice when cranking I've seen the engine speed touch 180 for a moment, I've also seen it touch 4000 rpm or so, this is while cranking. But 99.8% of the time it stays on 0 rpm.

^ Btw I havent known this all along, just came to notice a question in the Service Manual saying "Does your tech needle move up while cranking?" - Made me think about the CAS on it's way out.

Suggestions? Cheers again.

Edit: The CAS itself spins smoothly, no clicking, friction, or problems. There was also no dust inside the CAS at all. Are they cleanable/servicable? I see more screws inside the CAS but I dont want to dig that deep yet.

Edited by GTRPowa
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its a 32 gtr... they have plastic fuel tanks.

try this. disconnect injector main plug, take plugs out. crank engine over to clear out fuel, burn off spark plugs if they are dripping in fuel. put back together and then take hose off the intake plenumn (the cooler pipe hose) and crank the engine while someone sprays some aerostart into the plenumn. if the engine fires into life you defo have a fuel related problem. if no fire then its going to be something like ignitor, cas or AFM, but even then if you have spark it seems unlikely. as an engine will fire with no AFM plugged in.

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also to check the cas is working you can turn the ignition on and turn the cas over by hand. the injectors should click one at a time until all 6 have c licked. you can also test spark using this method also. if you have both the cas is fine.

Yes this is what I have done and I can't hear the injectors. I also had my FC controller with me and it was always sitting on 0 rpm, no matter how fast you turn the CAS.

I've borrowed an identical CAS from a friend, installing it tomorrow. I'll post my results when I get up. Night shifffftttt.

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I have seen quite a few people (including myself once upon a time) install the CAS back on the bracket with no front cover or spacers.

You either run the front cover, or you have to space the CAS out from the bracket, doing neither will wreck them quickly.

Won't be your issue if your running front cover/spacers but.

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Ok, turns out it was the CAS plug. I got a mates CAS, plugged it in, no difference. I then plugged mine back in, and it was working. Installed it into car, stopped working.

Used electrical contact cleaner, and slightly bent the CAS prongs so it makes a better connection. Took the car out for a good 1 hour drive, all is well.

Thanks again for helping to solve this annoying problem.

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