VQ Statesman Starting Problem

[Bugcatcher]

Hi,

Having a bit of a problem starting my VQ II V8 Statesman.

I've had problems in the past with ignition modules, coils, fuel pump but this time i'm stumped. Engine just died on me getting into the cark park at work and had to get it towed. Noticed the fuel pump was noisy lately so changed that. No good.

Then tried for spark, it was there but decided to change the coil and plugs anyway. No good.

Ignition module is only 1yr old but tried another working module, no go.

The engine is getting fuel and there is fuel on the plugs after cranking it over.

There is spark at the plug.

ECM is giving the standard code '12'

A strange thing that does happen though is when I try to crank over the engine and plant the accelerator to the floor. The engine tries to start for a second. The only thing I can think of now is it may be ECM related or a sensor. Can the ECM give a code '12' and still be faulty. Also is there some info online with instructions how to test sensors like the TPS and MAP? Or is there a flow chart to fault and diagnose what the problem is?

Any help of suggestions would be of great help,

Thanks,

Andy.

[Morton]

It could very well be a CAS issue. Check the plug on the distributor, and check under the dizzy cap to make sure the hall effect sensor isn't broken. My HES plug was knocked loose once, and the car just spluttered to a halt. Couldn't start it again.

[Bugcatcher]

Thanks, will check out the plug on the dizzy. Not sure how to check the Hall Effect sensor but will do a search and try to bring up some info. With the CAS, V8's dont' have a CAS, do they? Thought only the V6's did.

[Bugcatcher]

Also, if the Hall Effect sensor has failed. Will it give a fault code? I have read that it may give a code 41 or 46. Can the HES fail and ECM NOT give a fault code while its in diagnostic mode?

[Haydz]

sounds like hall effect sensor to me.

i had the same thing happen a few months back.

[DeViLisanAnGeL]

Yes dead HES in the dizzy will make the car just cut out and do nothing. It happened to me about 3 or 4 years ago. I don't recall a code coming up either, but it was a while ago

[Bugcatcher]

Just an update, still trying to track this problem down. Seems to be intermittent. Will be okay for a couple of days then run a little rough for a few seconds then not start at all.

Just changed the Hall sensor in the dizzy along with previously changing the coil and swapped over the trigger module.

Now resortng to finding a set of wiring diagrams and test for faults in individual wires incase of a break. Very frustrating.

Thing is if I floor the accelerator and open the throttle right up when trying to start it, it will try to start for a couple of seconds. The other thing I could try is putting the original chip back in the computer and try that. I changed the chip when I put a different cam in when I rebuilt the engine but the engine should still run with the older chip, just not as well.

Does anyone know where I can get a set of VQ Stateman wiring diagrams online. As a last resort i will go out and buy a service manual but didnt want to spend $50 just for a couple of pages at the back.

Thanks,

Andrew.

[dirt drifter]

try checking your battery leads, make sure they are still in good nick and done up tight. my vs died on me a while ago, same symptoms (had fuel pressure, injector pulse, spark, no codes) it would give the tiniest cough when trying to fire but no go. then it miraculously fired up and got me home but after that it would run like a dog when warm.

turned out my earth lead had come loose where it bolts onto the motor, tightened it up and it ran perfect again

[the_boozer]

http://hadagutfull.net/pictures/VNV8-1.GIF
http://hadagutfull.net/pictures/VNV8-2.GIF
http://hadagutfull.net/pictures/VNV8-3.GIF
not really what you asked 4 if i find the vq book Ill scan them
i didnt do real well last time.

hth Stevo