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Diagnosis Rb: Wha'ts The %#^$Ing Problem?

Cowboy1600

By Cowboy1600,
in Engines & Forced Induction

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Cowboy1600 Grand Master

Cowboy1600

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You need to check injector PULSE and coil spark first. If you don't have either one, then yes, CAS is most likely

Coil spark by sticking a screw driver or something similar into the coil pack and seeing if it'll spark to the block? Or any other way you recommend?

Injector pulse by pulling one out? Of is it easier to intercept the injector signal and hit it with a multimeter?

JonnoHR31 Grand Master

JonnoHR31

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ok. pull no1 coilpack out of the cradle, put the spark plug in the bottom of it and make sure its loom is plugged in. earth the threaded section of the spark plug somehow (i rest it against a screwdriver thats sitting firmly against a clean part of the head). pull the cas out, just undo the 3 bolts and carefully remove it, leave it plugged in. turn the ignition on and slowly turn the cas counterclockwise (looking at it from the shaft side), check for spark and listen for the injectors ticking. if you get either your cas is working fine, assuming of course the drive teeth are fine.

tridentt150v Grand Master

tridentt150v

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Use a jumper lead for the spark plug, much easier. Clamp one end to the motor, and clamp the sparkplug in the other end with the sparkplug plugged into the coil and loom like you normally would.

PM-R33 Grand Master

PM-R33

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I can't help but think it's the CAS.

Do I just take it off the base plate (ie, undo the couple of small screws) or do I need to take the base plate off as well?

Yep ubolt the three screws, unclip the wiring and then just pull it out. Mark where the bolts were roughly aligned first to be able to put it back in the same spot.

Once it is out just spin the shaft and see how it feels. Like I said. There should be no resistance what so ever. When they snap the shaft it feels like grinding against sand.

Everything really makes it sound like the CAS so I would suggest doing this first prior to anything else since it is the easiest thing to do.

AngryRB Grand Master

AngryRB

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used to have a vl turbo and when the airflow was on the way out, it puffed alot of fuel and black smoke out the back, very similar to what your talking about, then eventually wouldnt start at all,

have you ruled the airflow out??

Cowboy1600 Grand Master

Cowboy1600

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used to have a vl turbo and when the airflow was on the way out, it puffed alot of fuel and black smoke out the back, very similar to what your talking about, then eventually wouldnt start at all,

have you ruled the airflow out??

I picked up another one, which I can't be certain is working, but it made no difference. Aldo, the voltages seesm close (althought I need to confirm the V when cranking - my memory may not be accurate).

Count Grantleyish Grand Master

Count Grantleyish

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Fairly sure a Skyline will start start even without an AFM signal, just goes into limp mode, so I don't think it would be that.

With stock ECU, yes but don't know about PFC.

The Dan Grand Master

The Dan

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Shit I forgot about one small thing. You may have a split or dislodged intercooler pipe.

Check for leaks. AFM swap outs will not diagnose this and it will foul the crap outta your plugs. It will also cause it to run crap and basically every other symptom you described

PM-R33 Grand Master

PM-R33

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Shit I forgot about one small thing. You may have a split or dislodged intercooler pipe.

Check for leaks. AFM swap outs will not diagnose this and it will foul the crap outta your plugs. It will also cause it to run crap and basically every other symptom you described

Should still be able to start the car with throttle open though.

Everything really is pointing to a broken CAS spindle. As the starter motor spins the engine manually during start the ECU receives no signal from the CAS so won't fire any injectors or spark plugs to initiate combustion since it doesn't know the engine is turning over.

The Dan Grand Master

The Dan

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actually i can confirm that it would start, mine does without the airflow, just wont rev up pinch.gif ( with standard computer)

Yes, until the spark plugs are fouled....which takes about 5.3 seconds....and, unplugging an AFM is different to having one plugged in with no values being read

Should still be able to start the car with throttle open though.

Everything really is pointing to a broken CAS spindle. As the starter motor spins the engine manually during start the ECU receives no signal from the CAS so won't fire any injectors or spark plugs to initiate combustion since it doesn't know the engine is turning over.

Yeah IF he has no spark and no injector pulse, but having a blown cooler pipe or a split one or even a semi large vacuum leak near the plenum will stop if from running. Details are vague over the internet so we don't want to rule out basics until they have been thoroughly checked

Cowboy1600 Grand Master

Cowboy1600

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Yes, until the spark plugs are fouled....which takes about 5.3 seconds....and, unplugging an AFM is different to having one plugged in with no values being read

Yeah IF he has no spark and no injector pulse, but having a blown cooler pipe or a split one or even a semi large vacuum leak near the plenum will stop if from running. Details are vague over the internet so we don't want to rule out basics until they have been thoroughly checked

I've had a good hunt around for a split in any of the intake. Haven't found anything, but it was probably an 80% look, if that makes sense. It was running at the time, which would no doubt have helped substantially.

I will try and get an injector out, double check the spark and if nothing, pull the CAS off tonight.

I'm trying to be as thorough as possible so people can refer back to this as it seems to be a common problem caused by a number of things. If I can say "these were the EXACT symptoms, this is what I checked, this is what I found, this is how I fixed it," I'm hoping it will help others.

DVS JEZ Grand Master

DVS JEZ

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Go to repco or similar and buy a noid light.

This little guy plugs into the injector plug(easily without removing the plenum an fuel rail) and when u crank the noid light should flash. If it doesnt then there is no injector pulse.

Do some basics, check all fuses etc, then if possible borrow a mates CAS to try.

Cowboy1600 Grand Master

Cowboy1600

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Now the fun starts.

JDMSpares wants a piece of my arse, but has made it abundantly clear they do not wish to use lube. $180+del for a CAS - tell him he's dreaming.

Anyone got a Neo CAS they want to sell to me? The going price looks to be more around $60-$90

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