Car Stalled And Won't Start, Turns Over, Has Spark And Fuel, Ideas?

[Rolls]

So my cas/cam or something has been making a strange sound on high boost when the engine torques over, dyno operator put a screwdriver to it and reckon'd the cas bearing was going, said it might die in a month or 2 years, but I should look into it, was planning on doing so shortly.

Anyway a day later (today) was driving along, reved out first gear and then coming to a stop in 2nd on deaccel around 2.5k it made a weird bang/pop almost like a misfire through the intake now that I think about it and it won't start. I pulled a coil out and it has spark, also stuck a test light in the injector loom and it has fuel pulse, fuel pump primes and I can feel the pressure in the fuel return line.

Car tries to turn over but jerks around a bit and only splutters every few seconds, doesn't even try and start, I am fairly certain that the cas must have shit itself but if it wasn't the cas could anything else cause these symptoms if I have fuel and spark? If the engine had shit itself internally it would surely start but just sound horrible, so I'm basically ruling that out atm. Same goes for afm or other sensors, if they died it would still start just run like absolute shit instead.

Going to ride down tonight when I fix my bike and pull it off, will get a consult cable on there tomorrow as well but if anyone has any other great ideas to check out I'd love to hear them.

Cheers.

Edited February 23, 2011 by Rolls

[Plan-FAILURE]

So my cas/cam or something has been making a strange sound on high boost when the engine torques over, dyno operator put a screwdriver to it and reckon'd the cas bearing was going, said it might die in a month or 2 years, but I should look into it, was planning on doing so shortly.

Anyway a day later (today) was driving along, reved out first gear and then coming to a stop in 2nd on deaccel around 2.5k it made a weird bang/pop almost like a misfire through the intake now that I think about it and it won't start. I pulled a coil out and it has spark, also stuck a test light in the injector loom and it has fuel pulse, fuel pump primes and I can feel the pressure in the fuel return line.

Car tries to turn over but jerks around a bit and only splutters every few seconds, doesn't even try and start, I am fairly certain that the cas must have shit itself but if it wasn't the cas could anything else cause these symptoms if I have fuel and spark? If the engine had shit itself internally it would surely start but just sound horrible, so I'm basically ruling that out atm. Same goes for afm or other sensors, if they died it would still start just run like absolute shit instead.

Going to ride down tonight when I fix my bike and pull it off, will get a consult cable on there tomorrow as well but if anyone has any other great ideas to check out I'd love to hear them.

Cheers.

Sure the pop wasn't an intercooler pipe breaking its seal? That would give you the symptoms you have I'd say and its consistent with your boost up in 1st follwed by the breakdown.

Edited February 23, 2011 by Plan-B

[Rolls]

Checked all pipes, Ive blown one off before and it starts and runs just like absolute shit and stalls straight away. This time it won't even kick over, makes one splutter every few seconds if that.

Will go check more carefully when I go back.

[Plan-FAILURE]

So you turn the key and nothing? No crank?

[The Dan]

The CAS sends the signal to the ECU for engine position so if it wasn't working, you'd have no injector pulse or spark

[Plan-FAILURE]

The CAS sends the signal to the ECU for engine position so if it wasn't working, you'd have no injector pulse or spark

Shit you beat me to it you smart flamin mongrel!

Air leak somewhere I'd say, if your 100% you have fuel pressure...

Edited February 23, 2011 by Plan-B

[luvpsi]

mmm this is a tuff one but i agree with elite racing the cas controls the ecu meaning controls spark and fuel so im stumped

[Plan-FAILURE]

In your oroginal post Rolls you talk about if the engine was screwed internally it would start but just run like crap. This isn't always the case.

Whats got me is the POP sound. What goes POP and causes the engine to fail?

So, lets get into the physics of it all.

A pop is generated by a force of pressure being released

This source of pressure in our cars can be two things. air pressure or boost pressure and would be subsequently released due to a voluntary disconnection somewhere in the air/turbo systems.

Check your BOV

Check all air and fuel lines

Check your fuel system again and inspect the rail

Check throttle cable

Edited February 23, 2011 by Plan-B

[zebra]

Broken the nose/drive off the exhaust cam?

[Rolls]

So you turn the key and nothing? No crank?

cranks over roughly but doesnt start, barely even tries to start tiniest splutter every second or so

thought it might be something internally as it sounded very rough when I first turned it over, eg it cranks for like a second, sort of stops like its stuck then keeps cranking and repeats. I figure if something was f**ked enough to jam it every few revolutions it would be making a much worse sound though and almost certainly wouldnt turn over at all.

When I first heard the noise I thought I had run over something, really hard to remember if it was a pop or a bang like something breaking.

Sounds like I'll have to check for air leaks in the intercooler piping, failing that is there anything else you guys can think of? the fact I get spark and fuel means the cas must be working I am assuming?

Breaking the nose off the exhaust cam was actually what the dyno operator suggested would happen, however I am 100% sure I am getting spark so if this happened is it possible for me to get any spark at all? I guess it could still turn it just not properly.

After checking for all air leaks I will take the cas off, I should be able to see if this is the case then yes?

Edited February 23, 2011 by Rolls

[Plan-FAILURE]

check my post above dude. also zebra has made a pretty wild call but would give you those symptoms if it DID happen lol

Edited February 23, 2011 by Plan-B

[Rolls]

Well off I go, I'll report back.

[zebra]

cranks over roughly but doesnt start, barely even tries to start tiniest splutter every second or so

thought it might be something internally as it sounded very rough when I first turned it over, eg it cranks for like a second, sort of stops like its stuck then keeps cranking and repeats. I figure if something was f**ked enough to jam it every few revolutions it would be making a much worse sound though and almost certainly wouldnt turn over at all.

When I first heard the noise I thought I had run over something, really hard to remember if it was a pop or a bang like something breaking.

Sounds like I'll have to check for air leaks in the intercooler piping, failing that is there anything else you guys can think of? the fact I get spark and fuel means the cas must be working I am assuming?

Breaking the nose off the exhaust cam was actually what the dyno operator suggested would happen, however I am 100% sure I am getting spark so if this happened is it possible for me to get any spark at all? I guess it could still turn it just not properly.

After checking for all air leaks I will take the cas off, I should be able to see if this is the case then yes?

you will still get spark as the cam belt runs the cam gear with attaches to the nose of the crank so it would still be turning.

I would pull the cam cover off and have a look

[Plan-FAILURE]

cranks over roughly but doesnt start, barely even tries to start tiniest splutter every second or so

thought it might be something internally as it sounded very rough when I first turned it over, eg it cranks for like a second, sort of stops like its stuck then keeps cranking and repeats. I figure if something was f**ked enough to jam it every few revolutions it would be making a much worse sound though and almost certainly wouldnt turn over at all.

When I first heard the noise I thought I had run over something, really hard to remember if it was a pop or a bang like something breaking.

Sounds like I'll have to check for air leaks in the intercooler piping, failing that is there anything else you guys can think of? the fact I get spark and fuel means the cas must be working I am assuming?

Breaking the nose off the exhaust cam was actually what the dyno operator suggested would happen, however I am 100% sure I am getting spark so if this happened is it possible for me to get any spark at all? I guess it could still turn it just not properly.

After checking for all air leaks I will take the cas off, I should be able to see if this is the case then yes?

Yeah mate from what you say, if the behaviour of your engine internals has changed (your "feeling rough" description) then I can't imagine it would be an air leak unless you have more than one problem. I know personally that trying to describe the characteristics of a noise while driving can be difficult. Is it possible the "pop" could have been something flicking up into your engine from the road?

Drain your engine oil and check for metal fragments. That should give you an indication if its internal.

I look forward to hearing about this one...

Edited February 23, 2011 by Plan-B

[The Dan]

you will still get spark as the cam belt runs the cam gear with attaches to the nose of the crank so it would still be turning.

I would pull the cam cover off and have a look

agreed. if you have no air leaks, take off the cas and timing cover to see if anything has gone walkabout

[jrm]

you will still get spark as the cam belt runs the cam gear with attaches to the nose of the crank so it would still be turning.

I would pull the cam cover off and have a look

If the nose has snapped off so the belt is still turning (along with the cas) wouldn't that mean the cam itself isn't turning - meaning valve on piston contact (mind you the OP said it turns over and then gets 'stuck' - so maybe that's what's happened?)

... Just thinking outloud based on what others have said anyway ...

Definitely sounds like time to get that timing belt cover off anyway ...

[Rolls]

Tried to start it and got some horrible backfires, sounded like I had no exhaust, then it wouldn't start again.

Checked all intake piping thoroughly and found no evidence of leaks or blown hoses.

Pulled the cas off and the drive looked intact although VERY rusty, lots of rust in the drive and where it attaches. Manually turned the cas and I could hear each cylinder spark and each injector pulse, made a few pretty crazy backfires as well. Tried starting it without the cas and the otherside of the drive appeared to turn with the engine fine, a good poke with a screwdriver and it felt firm and definitely not cracked or detached. Couldn't see anything else a miss under there either.

Tried starting it again with everything off and it actually tried to kick over a few times but never close to starting, ended up killing the battery from trying so many times.

Going to try the consult tomorrow, until then I am completely stumped, if it is getting spark and fuel it either has no compression or the timing is messed up due to the ecu or something? I guess the cas could be damaged internally as well, hopefully the ecu can tell if its failed by it giving bad data as well as it just not being there, if so the error codes should help me tomorrow.

Edited February 23, 2011 by Rolls

[ronnydotk]

Have you actually checked a fuel line for pressure? If you have pressure in the supply line and injector pulse then i am happy with that. I believe you have spark. Which leaves only compression (if cam belt is still in one piece then it's hard to see any reason why all cyls have lost compression - you can tell low compression by the way it winds over)

One other thing to consider then:

If you for whatever reason had a lack of fuel to a cylinder (fuel starvation under hard acceleration?) a backfire through the intake isn't unusual.

A backfire through the intake can damage the "hotwire" in the AFM.

The AFM is the main signal used by the ECU (along with the CAS) to calculate a base fuel load and ignition timing.

If the AFM has been damaged by the backfire then it is unlikely your engine will run at all.

This happens quite alot to cars fitted with venturi type LPG kits (not really relevant here). LPG systems falls out of tune (lean), backfires, blows AFM apart, no go on petrol (runs on gas as gas processor doesn't need AFM to operate).

Anyway, your scan tool will tell you if afm is working or not.

cheers

[Rolls]

I thought the car would start with the AFM unplugged and it will just be very rich and not rev much above idle? or am I wrong.

[DVS JEZ]

Try another CAS. I snapped a CAS and it gave me the same symptoms.

Pull the hat off the CAS and check the shaft and disc