Crank but no start Monaro VXR
Discussion
Having completed some work on the car i am at a point where it cranks but doesn't fire. At this point I am going to have to own up to being a complete and utter numpty 
I had been refitting the steering rack and reconnecting the steering column which required the ignition key in place to release steering lock, working with the battery out of the car I forgot to take the key out of the ignition, and yes, you guessed it, the following day replaced the battery and reconnected terminal connections at which point the air turned blue with a series of expletives i won't repeat here.
I have connected GM Tech2 to the car and run the diagnostic feature ( I am very new to Tech2 ) it appears to show no communication with the ECU, have I fried it, is it likely that connecting the battery with the ignition switched to on, caused a power surge and damaged the ECU ? Any abuse coming my way will be taken well I promise
I had been refitting the steering rack and reconnecting the steering column which required the ignition key in place to release steering lock, working with the battery out of the car I forgot to take the key out of the ignition, and yes, you guessed it, the following day replaced the battery and reconnected terminal connections at which point the air turned blue with a series of expletives i won't repeat here.I have connected GM Tech2 to the car and run the diagnostic feature ( I am very new to Tech2 ) it appears to show no communication with the ECU, have I fried it, is it likely that connecting the battery with the ignition switched to on, caused a power surge and damaged the ECU ? Any abuse coming my way will be taken well I promise
L2VXR said:
Also I hope you've not uncentered the wheel or you could also damage the clock spring for the air bag.
Only a minimal amount of movement with the steering wheel whilst disconected from the rack, just enough to allow the end of the column to drop into the socket on the rack, so hopefully all good there.LS2Noir said:
Only a minimal amount of movement with the steering wheel whilst disconected from the rack, just enough to allow the end of the column to drop into the socket on the rack, so hopefully all good there.
Yes as long as your wheels are in the same position as when you disconnected jiggling to get the joint together is OK. Problem only if you rotate the steering wheel from its original position Edited by L2VXR on Wednesday 8th May 21:34
L2VXR said:
Have you connected the candi module to the tech2 as you'll need too on a small boot VZ
I will have a look at this as not using a candi module, i am using Tech2Win software on a laptop via VXDIAG VCX NANO GM GDS2 obd interface and USB cable. I am new to the software and interface, so will do some more research and have another look tomorrow, thanks for the feedback 
LS2Noir said:
I will have a look at this as not using a candi module, i am using Tech2Win software on a laptop via VXDIAG VCX NANO GM GDS2 obd interface and USB cable. I am new to the software and interface, so will do some more research and have another look tomorrow, thanks for the feedback
In that case I haven't a clue, all I know from connecting my handheld tech2 is that you need the candi module to connect to a small boot car. I believe you don't need it on big boot cars but can't confirm. stevieturbo said:
It would be extremely unlikely that could cause any damage, if that is genuinely all you did.
Does anything in the car power on ? Does the fuel pump prime on key on ?
Thanks for the reply, dash lights up as normal, engine turns over but doesn't fire, 1st thing I noticed when I first tried to start her up was that I didn't hear the fuel pump prime the system, and thought the immobilizer might be preventing the car firing. More investigation required this end.Does anything in the car power on ? Does the fuel pump prime on key on ?
Hearing that it's unlikely i've fried the ECU makes thing easier, it's looking more like the diagnostic tools i'm using aren't communicatiing with the ECU at present.
My Tech2win also says those 3 modules don't communicate. The car runs fine, and it absolutely would not without those modules communicating, so I wouldn't worry about that bit!
Have you got the VZClusterMod software? If you do, log the output from that and post it, I can confirm that the modules are communicating from that (they all send a heartbeat type check in response constantly)
Feel free to PM me if easier, I'm off work tomorrow so can check stuff on the car if you need.
There's a schrader valve on the fuel rail, with ignition on the fuel rails should be at 56psi or so. Put a cloth around that schrader valve and give it a jab, 56psi should mean you get a pretty obvious spray of fuel if there's pressure.
The fact it's cranking means the modules are communicating I'm pretty sure, as the crank signal isn't from the key turn, it's a deliberate signal from the BCM (or one of the modules anyway) that's sent once all the others have responded properly.
Have you got the VZClusterMod software? If you do, log the output from that and post it, I can confirm that the modules are communicating from that (they all send a heartbeat type check in response constantly)
Feel free to PM me if easier, I'm off work tomorrow so can check stuff on the car if you need.
There's a schrader valve on the fuel rail, with ignition on the fuel rails should be at 56psi or so. Put a cloth around that schrader valve and give it a jab, 56psi should mean you get a pretty obvious spray of fuel if there's pressure.
The fact it's cranking means the modules are communicating I'm pretty sure, as the crank signal isn't from the key turn, it's a deliberate signal from the BCM (or one of the modules anyway) that's sent once all the others have responded properly.
LS2Noir said:
L2VXR said:
On the crank but no start, is the red immobiliser light flashing on the dash or dose it go out when the ignition is on
I'm away from the car at the moment, will drop you a reply on this at some point tomorrow, thanks again for your responses.LS2Noir said:
Immobiliser light ( and red led on radio unit ) flash as they should with ignition off, both stop flashing when ignition is switched on.
I'd assume then that the immobiliser is deactivating so the bcm is functioning.Reading an old post on a similar crank but no start issue it was suggested by a respected specialist to unplug the ecu for ten minutes and then try, ideally you need to get a scan though to know what's going on
If you have no luck locally, I can recommend emailing Wayne at Pro-Tune here in New Zealand, he has worked on and tuned literally tens of thousands of GMH V8 product is renowned in the LS world. He studied in America and does maps for cars all over the world, including Australia so that says something.
I only recommend him because I know he is a hell of a nice guy, very knowledgeable and passionate and a hell of a peddler in a Rally car.
sales@protune.co.nz
SturdyHSV said:
My Tech2win also says those 3 modules don't communicate. The car runs fine, and it absolutely would not without those modules communicating, so I wouldn't worry about that bit!
Have you got the VZClusterMod software? If you do, log the output from that and post it, I can confirm that the modules are communicating from that (they all send a heartbeat type check in response constantly)
Feel free to PM me if easier, I'm off work tomorrow so can check stuff on the car if you need.
There's a schrader valve on the fuel rail, with ignition on the fuel rails should be at 56psi or so. Put a cloth around that schrader valve and give it a jab, 56psi should mean you get a pretty obvious spray of fuel if there's pressure.
The fact it's cranking means the modules are communicating I'm pretty sure, as the crank signal isn't from the key turn, it's a deliberate signal from the BCM (or one of the modules anyway) that's sent once all the others have responded properly.
Hi SturdyHSV,Have you got the VZClusterMod software? If you do, log the output from that and post it, I can confirm that the modules are communicating from that (they all send a heartbeat type check in response constantly)
Feel free to PM me if easier, I'm off work tomorrow so can check stuff on the car if you need.
There's a schrader valve on the fuel rail, with ignition on the fuel rails should be at 56psi or so. Put a cloth around that schrader valve and give it a jab, 56psi should mean you get a pretty obvious spray of fuel if there's pressure.
The fact it's cranking means the modules are communicating I'm pretty sure, as the crank signal isn't from the key turn, it's a deliberate signal from the BCM (or one of the modules anyway) that's sent once all the others have responded properly.
Thanks for responding, no unfortunately I don't have the clustermod software at present, just had a read up on using the software, useful tool by the looks of it, are you using the clustermod software with the connection cable advertised with the software or the OBD interface and cable you would use with Tech2Win software.
Gave the shrader valve a prod, very little pressure on 1st prod, no pressure on second prod, that was the first thing I noticed when I tried starting the old girl, no sound of the fuel pump priming.
Gassing Station | HSV & Monaro | Top of Page | What's New | My Stuff