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-   -   Car Spits and Starts but dies almost immediately (https://blazerforum.com/forum/engine-transmission-35/car-spits-starts-but-dies-almost-immediately-107673/)

AnyDig60 Mar 20, 2026 06:57 AM

Car Spits and Starts but dies almost immediately
 
My Blazer ZR2 2004 cranks and spits for a second then stops as if it isn?t getting fuel.

The vehicle is hot wired and I am thinking that it is causing the problem, but I cannot figure out how to bypass it especially since it?s giving the same voltage with the car in ?ON? and ?START? (2.00v) so I do not understand, I am planning on just replacing the whole key and mechanism this weekend.

Ive replaced Fuel Filter, Fuel Pump, Crankshaft Position Sensor, Battery and even tried spraying starting fluid, and jumping the relays to no avail.

let know if I am doing anything wrong, anything I haven?t tried so I can attempt something new.

LesMyer Mar 20, 2026 09:44 AM

I have no idea how you would "hotwire" a 2004 Blazer. Certainly security system is preventing it from starting.

This (below) contains the passlock sensor (not the lock cylinder/key) and will need installed (along with a new lock cylinder). Then you need to do the procedure that sets the BCM to the new passlock sensor code. Only then will the BCM send a happy signal to the PCM, which in turn allows the fuel injection to work.


AnyDig60 Mar 20, 2026 09:48 AM


Originally Posted by LesMyer (Post 758912)
I have no idea how you would "hotwire" a 2004 Blazer. Certainly security system is preventing it from starting.

This (below) contains the passlock sensor (not the lock cylinder/key) and will need installed (along with a new lock cylinder). Then you need to do the procedure that sets the BCM to the new passlock sensor code. Only then will the BCM send a happy signal to the PCM, which in turn allows the fuel injection to work.

https://www.amazon.com/APDTY-Ignitio...evrolet+Blazer

exactly what I was thinking, I wasn?t the one who set it up, but everything I found said it should work(?) anyways If you have something that can fix it that?s perfect for me.

LesMyer Mar 20, 2026 11:30 AM

Are you speaking about bypassing passlock using a resistor? AFAIK it's not reliable and I do not recommend it. What is the entire backstory here? Need it all in order to help.

AnyDig60 Mar 21, 2026 03:22 PM

Well yes it is hot wired (without resistor), and it seems like security light isn?t on (I?ve replaced the gauge cluster to see). Backstory is it used to run till the guy I bought from parked it (I know quite a story) but it would stop running after a while, now it cranks and spits and try?s to start but then dies. I don?t believe that it?s anything to do with security as of right now.

AnyDig60 Mar 22, 2026 10:39 PM

https://cimg8.ibsrv.net/gimg/blazerf...e5d3a9aef.jpeg
Got a ?new? gauge cluster that works, and the security light is on, everything besides the PRDL seems to work. I now assume it actually is security related. Anyways got a new Key Lock Cylinder and Key installed, but the security light doesn?t go away after rewiring everything back up from Hotwire, and attempting the relearn. CEL is on but can?t get OBD2 to read anything (everything seems to be working for it to read) also side note it can charge the OBD2 and read battery volt. Attempting stuff tomorrow.


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