Pk3 bypass

[albert]

01 been sitting 3 years, 80,000 miles was running when parked, replaced fuel pump, cranks and fires putting fuel in intake but no fuel getting thru injectors so thinking security system. We only have valet key, and of course these keys have resistors inside plastic cover so can't read key, looked for bypass on internet but couldn't find one, any help getting this beautiful car going would be appreciated...Thanks

[Paulaurora]

cheaper to buy new key from ebay and program it if it still the same it might not be security system issue. 2g 98% ever had those issues. Unless someone really mess things up with electronics in the car.

[albert]

Thanks, no car has never been messed with, they parked in a building when a window wouldn't roll up...been checking for mice chewing on wire, will give new key a try.

[Paulaurora]

it might be the ps3 key issue(but most likely not) but even bypassing might cost more and sometimes u might end up having other issues after bypass. Of cause i would check the fuses as well.

[tigger]

Is the security light on?

Any messages on the DIC?

Can you check the fuel pressure at the rail? (key on, engine off)


FWIW, PK3 uses RFID (radio frequency identification) so there's no resistor in a PK3 key to read. And if I'm not mistaken, you can't "program" additional keys without a master (black head) key.

[RCA1186]

Could be a Passkey problem, but I thought that Passkey also disabled the starter. So wouldn't it not be cranking?

[tigger]

^Good catch Rob!

Straight from the owner's manual;

When the PASS-Key III system senses that someone
is using the wrong key, it shuts down the vehicle’s
starter and fuel systems. The starter will not work and
fuel will stop being delivered to the engine.


So... If it's turning over, it's not a PK3 issue.

[albert]

Genuine mystery at this point, fuel pressure good, no message on DIC, security not flashing when cranked.....according to one "expert" the security system has 2 sides one side controls starter, one side the fuel....maybe crank sensor? Thank you everyone...We shall overcome.

[RCA1186]

Sure you have spark? If so I'd say crank sensors are an educated guess, but just that though - a guess. You have no codes or pending codes? I was going to suggest looking for rodent damaged wires as you said it was parked so long , but I see you already did that.

[albert]

Despite being a Green Bay fan like one of my daughters, Thanks 😀, yes has spark, gas thru intake fires right up, going to talk to GM dealer tomorrow, take it from there. Go Cowboys.

[Randy T.]

Might test your ignition switch to rule that out.

[tigger]

OK, so it'll run if you spray fuel into the intake, and you have good fuel pressure at the rail (wanna say 41-47 psi), correct?

I'd check the injector wiring harnesses and fuses. But I have to ask, did you dump the 3 year old gas?

[albert]

Dumped old fuel and cleaned out tank when we installed new fuel pump but others cranked engine before I got there so will test fuel injectors as we have time, has spark, vin numbers starting with 1 or 4 can accept new key after the 30 minute reset thing which we did so it's probably not security system, fuses look good, no codes on my little tester, may rent scan tool.....Thanks...onward.

[Paulaurora]

What state are u in?

[albert]

Car is in Meridian Texas, SW of Fort Worth 

[albert]

Voltage to injectors but no signal from ECM,  PO412 code showed up, air pump, from what I read shouldn't keep it from starting.

[sempar]

Did you verify that the injectors were turning off and on when cranking? If the voltage is constant at the injectors when cranking that could indicate a possible defective ECU. The ECU completes the path to ground thru the drivers.

The other possibility, as mentioned, is no ignition reference signal. Lack of signal will cause the ECU to cut off fuel to the injectors.

John

[albert]

No pulse at injectors when cranking, don't know how to test ignition switch.

[tigger]

I can post the wiring diagrams.

3.5 or 4.0?

[albert]

Thank You that would help, don't want to just start replacing parts.....so I've been a little slow understanding that the pk3 system can be working but the ignition switch can be bad...I think Ha. I have an 01 Suburban but never had a problem, at least not with the security system.

[tigger]

Right on.

So, 3.5L V6 or 4.0L V8? Don't wanna lead you down the wrong path...

[albert]

3.5

[tigger]

3.5 PCM/IGN SWITCH power and grounds.

[albert]

Thank you tigger...I tighten ground straps I could find and now the car is trying to start, ran out of time and battery but we will see.

[albert]

I still would like a pk3 bypass but I probably started this out all wrong but it's a real hunt with a non running car with a computer. 3 years old gas causes problems, that may be our main issue.

[tigger]

Well, there are bypass "modules". You have to have one for remote start/aftermarket alarm systems. It's basically a wired bridge, you place a valid key into the module box, wire it up, and it makes the connections. Only bypass I know of... Works well but if you go this route get a cheap ebay PK3 key, program it and cut the blade off before you put it in the box. The module only needs the transponder and no sense in leaving a functional key inside the car.

Yeah, may need to pull and clean the injectors. Sounds like you're making progress though...

Keep us posted!

[albert]

Thanks I sprayed a cleaner in the fuel rail seemed to help some, if needed I'll probably pull the injectors after church tomorrow. So for others, car sat for 3 years fuel sock was in pieces, grounds had become corroded, (my opinion is they could use more grounds)fuel injectors stopped up.

[albert]

Behold....clogged fuel injectors, pulled front 3, cleaned what we could only one showed good flow, reinstalled CAR STARTED, obviously not firing on all cylinders but still. We will continue to clean or maybe buy recons. So combination of bad fuel pump, bad ground, and dirty fuel injectors but things are looking up. Thank you everyone for the input. I really like these cars.

[tigger]

Hey, hey, way to run it down!

Don't you love it when it's something simple, lol!

[plato442]

Definitely want to clean the fuel system of 3 year old fuel!!!