04 Rendezvous Crank No Start Puzzle

[dee_dee_railed]

Hi Guys,
Just met a woman, trying to impress her and it's not going well.
2004 Buick Rendezvous with the 3.4l.
Will crank but not fire. Will fire when carb cleaner is sprayed into the intake. No codes thrown while cranking.
We are getting spark and pressurized fuel is in the rail, have not tested the exact PSI.
Red security light will blink in off position, not coming on while cranking or in on position.
A few months ago, the ignition cylinder professionally replaced, the fuel pump was unprofessionally replaced and suspect it's incorrect, and the crank position sensor was also replaced.
Leading up to the no start condition, it died a few times but would restart after a while.
Have unsuccessfully attempted the relearn procedure with the Pass-key III system.
Have read that if one injector dies, the entire system shuts down. Have not yet pulled the intake to test.
Any help would be greatly appreciated.
-Brett

[anotheridiot]

no expert here, just been thru this alot. best thing to pull the plugs and spin it to check for compression, if you only have compression in a couple cylinders then the timing belt broke or slipped. Crank is turning with the starter, cam is not. You would have some compression in some cylinders since valves are closed and not moving, its like double compression, others are open. If you have compression in all 6, then you look towards outside problems. Probably easier to pull plugs than to pull valve cover(s). If the plugs are stingy, just take out the ones that are not, wait til the car runs again to pull the ones that are hard after warming up the motor.

As far as the relearn, there are plenty of ways to do it. Is it a chip or no chip key? if its a no chip and security lite is on, then the try to crank, leave til security lite goes off, try to crank, wait for security lite to go off, as many times as necessary. Each time it takes up to 10 minutes to relearn the key.

The other suggestion is go to on that many times without trying to crank, but my 2003 avalanche just worked the other way. That was the one I rewired last year, used the old computer since the new one would not get past security and the car has been running on default settings all this time.

The belt is where I usually end up after trying to change everything.

[dee_dee_railed]

Believe the new key is a chip unit. Security light does not come on while cranking or in start position.

[anotheridiot]

I am pretty sure the passkey stops the flow of fuel and spark, it is supposed to run for a few seconds and shut down. Blinking security lites happen if doors are open too. Pretty sure the transponder relearns were just off to on with a chip, no try to start but the security lite is supposed to be on. If you think its the problem, try disconnecting the battery for a while (if you did not already do that) before attempting the relearn. I have 97, 98, 99, 02, 03, 03, 03 vehicles with no chip keys. Our 98 malibu would just turn off while driving after 25 minutes or so, pop it in neutral, start again, keep driving, but if it was in park, you had to wait the full 5 minutes to start again. There are resister tricks to do in the BCM to bypass them, but need to make sure it is the issue.

[dee_dee_railed]

Starting to move away from Pass-Key issues, everything appears to be working as it should there.
Pulled the oil filler cap while somebody cranked, was able to see the valves operating which means the timing belt is still in place. No gas smell when plugs are pulled, either.
Thinking injector(s), but no codes? Or CPS, no codes? Or the wiring in between.

[anotheridiot]

I have had 2, yes 2 GM 3.1 camshafts break in the middle. They are simply lobes welded to a hollow tube. If you have no codes it sounds mechanical. You pulled all plugs and cranked the motor and got compression from all cylinders or just watched the ones you can see thru the oil cap?

You usually have one general code for injectors before it isolates each one to a code and that is clear. You have fuel, spark, no codes.

If you can locate the BCM, maybe you can see if someone already did the resister solder in between the black and yellow (usual) wires to bypass passkey but the resister failed or shorted as a last passkey check. But with mine, no cranky, nothing usually with passkey problems.

[hauen]

My son's '03 Saturn had the same problem, it was the crank sensor, they go bad but don't throw any kind of code. If you try it, don't dick around with cheap Chinese junk, just bite the bullet and buy an OEM sensor, or a Delphi or Delco or one of the bigger brands. I know they're all made in China now, but there is a difference, I found that out the hard way.