Can anyone help....The car will start on LPG, but not Petrol, so even though it looks like the ignition switch's up the swanney, I think this might be a workaround for now.....any ideas?

Ta muchley.

 

Exactly what 'immobiliser' are we talking about? The Passlock system from GM, some aftermarket security system, or the kill switch that I believe is required on American imports to the UK (which we do not have on Blazers over here)?

 

Hi, thanks for the reply.
It's not an after market immobiliser, I "think" it's the passlock. The security light is permanently lit, and it turns over and then immediately dies on petrol. The LPG is an aftermarket obviously, and it starts on LPG no problem although the security light is still on. Does this help??
I do computers and kids, not cars....but I'm willing to learn cos I love the "beast"
Thanks.

 

That does sound like the security system is preventing it starting. I had a similar problem and there is a proceedure in the user manual to re-learn the remote key fob, if you don't have a user manual, I'll look it up. If not, it could be the fuel pump, thought I don't know why the security light is on.
What LPG system do you have, I have a dream OMVL which I'm very happy with, but the coolant tempreature to switch to LPG seems to need adjusting when the weather changes to avoid hesitation when it first switches to LPG.

 

Not sure which LPG system - was on it when we bought the car. Sorry. I do know that id's not happy starting on LPG, and the previous owner said it was not good to start that way....have no choice at the moment though.

 

I know the exported version has more bells, gongs, and whistles on the immobilizer. I don't know if this will work on it..... You should depower your LPG system before doing this, in the trucks brain it's not supposed to start. On the US version: Turn the key on and try to start it'll try and stall. Security light will flash then turn on solid. Leave the key in the on position until the security light turns off. Turn the key off for 30 seconds and try to start it again (won't start). Leave the key on until the security light turns off, turn off for 30 seconds then..... After the third sequence of doing this the truck will start (US one anyhow). This assumes this no flawed parts in the security system, the modules simply don't have the same passlock code anymore, the process would resynchronize them.

 

The security system is different on UK models (I think this applies to all european models). Basically the immobiliser is disabling the fuel pump after a second or 2. When you unlock the vehicle using the remote fob the immobiliser is disabled for 2 minutes to allow the vehicle to be started. If your remote fob isn't working the only other way to make the fuel pump work is to enter a 5 digit code using the foglight switch. This 5 digit code is supplied on a red card with the vehicle when new. If you don't have it you will need to go to a GM USA dealer to get the vehicle hooked up to their scanner. Bauer Millet in Manchester have previously told me that they are the only place in the UK with the software to interrogate the security system & obtain the code on these vehicles. However other people have told me that Cadillac dealers can do this also? Fortunately I have never had this problem so can't speak from personal experience.
If you have the code & the owners manual the procedure for getting the car started can be found on page 114. If you don't have a manual I can scan & email you the instructions if you have the 5 digit code.
Incidentally - if you have the fob(s) but they don't appear to work are the batteries OK? Also, when you replace the battery you need to re-synchronise the fob to the vehicle. This can be achieved by holding the lock & unlock buttons down together for around 10 seconds or until the locks cycle (lock then unlock). Hope this helps.

 

@DaveHearne , maybe can help with user manual ? as i have 5 digits code , and no idea how to input , thanks

 

No problem. Am just about to send you a scan of the procedure from my owners manaul as a private message, cannot seem to insert it here.