crank but no start

cw41

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#1
Make
Chevrolet
Model
Impala
Year
2000
Miles
134,000
Engine
3.8
I've been chasing a ghost on this Impala trying to locate why it runs fine one day and the next it won't start. I checked several things when it ran, fuel pressure/regulator, voltage, etc and no check engine lite either.
I decided since I rec'd a replacement ignition key that has the passlock to install that in the switch module in the dash. the car shouldn't have cranked with using a new key the ignition module should have set a security light but didnt. the car cranks but will not start.
Is is possible that the ignition switch module has gone bad? I have another one coming under warranty that I will install and do the relearn process.
thanks for your time to reply.
 

billr

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#2
When it cranks but won't fire you have to determine which of the basic requirements is missing: spark? injector pulses? fuel pressure? spark timing? compression? We need to narrow this chase down or it could get expensive to just throw parts at it.

When it won't fire, have you tried disabling the fuel (pull injector fuse/relay) and suing a quick blast of starting-fluid? That may quickly show that this is *only* a fueling problem and we focus in that area.
 

©hester

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#3
Does this key have a chip in the blade of the key? Assuming you have the correct key, might it be possible that your intermittent problem could be a result of poor contact points within the ignition lock cylinder and the chip in the key?
 

cw41

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#4
When it cranks but won't fire you have to determine which of the basic requirements is missing: spark? injector pulses? fuel pressure? spark timing? compression? We need to narrow this chase down or it could get expensive to just throw parts at it.

When it won't fire, have you tried disabling the fuel (pull injector fuse/relay) and suing a quick blast of starting-fluid? That may quickly show that this is *only* a fueling problem and we focus in that area.
thank billr, its a hard thing to diagnos because when it runs, it runs exc then the next day or so back to nothing. when I have it running the fuel pressure is 48psi, voltage is 14.3 and no check lights. One thing I did notice is the lack of the security icon maybe the bulb to it burned out. when you put a new passlock key tumbler assembly into the ignition switch module in dash on this car, it should not crank at all but does?? I will try the starting fluid to check.
 

cw41

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#5
Does this key have a chip in the blade of the key? Assuming you have the correct key, might it be possible that your intermittent problem could be a result of poor contact points within the ignition lock cylinder and the chip in the key?
the key doesnt have a chip but the ignition key tumbler assembly has a passlock built into it that when installed in switch security module should need a relearn to crank at all. thats why I was leaning toward the ign module having a fault, its happened before. Many gm's of this late 90's early 2000 have the ignition in the dash instead of steering column. More nostalgic I guess?? thank you
 

©hester

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#8
Yes, B+ was dropping out of the ignition switch Even during driving, the car would quit. Chevy replaced the ignition cyclinder and all was fine.
 

cw41

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#9
sound like the same thing thats happening to me. did chevy replace just the key part or the module in the dash also? this car of mine has gone through two of each and now a third!
 

cw41

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#11
yep thats the part that has failed now a third time. wow did they ever charge you to fix it!! that part is around 25-35.00 now and about an hour labor to install. but I know when you go to the dealer its expensive. the first repair about 10 yrs ago cost me that much also. I've had to learn to fix things like this to stay out of the poor house. that part I refer to as the security switch module. Not the correct name I think its referred to as a switch that the key lock cylinder fits into. thanks for the info!!
 

nickb2

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#12
These can be bypassed with a resistor on yellow wire to circumvent the need to replace the passlock VTD(vehicle theft deterrent). I always have a couple dozen resistors on hand. Usually I find one that work on third or fourth try.

I was easier with the earlier version passkey as in such, if you had the key, you could physically read the resistor pellet with a DVM. With this newer passlock, it is hit and miss. I go from 500ohms, and go up 500ohm increments until my scanner tells me it accepts the handshake between PCM and BCM/VTD module. Once I find the right one. I simply integrate the resistor on yellow wire. You now have no theft deterrent, but who really wants to go through the hassle to steal a year 2000 chevy car 215000km's on it? Actually, scratch that, some idiots will steal anything just for fun. I am just joshing.

But that bypass saves a few hundred usually as you don't need to tow it to a shop or wait on parts while the car stays put. Resistors can be bought at any local electrical hobby store such as radio shack, if that still exists in the states. They closed up here, now I go to maddison or addison.

Here is a schematic of the system, notice yellow wire data line to tamper sensor. You see the resistor in the unit, that is the one you fool and send it directly to the BCM bypassing the entire ign passlock by skinnging the black wire and solder the cut yellow wire to it with the proper resistor. Hand shake with PCM is done through the DK green wire. You can use a screwdriver at this point to start the car or even install a push button as long as the tumbler turns to unlock the steering wheel.

Newer cars are not as easy to fool with the RFD chips. But thieves use frequency scanners and laptops now to steal high end cars. Nothing is theft proof to 100%, unless you buy one of these monkeys. Btw, isn't that a 2000ish malibu or impala in that trunk monkey video?;)

Screenshot (291).png
 
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nickb2

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#14
Yep, -18c to -25c wind chill last week ;):eek: We usually see that in jan or feb. Very rare for middle nov temps. Today, back to normal, but the snow is still there, not helping to thaw anything out yet, just reflecting back the sun rays, so even if it is +3c right now, nothing is thawing. We need an indian summer pronto. If not, some of my buddies in the snow plow industry are going to need some :money: cuz they did not foresee this so early.

About 3 foot of snow fall already in montreal region in one week. Worse in more northern regions where I used to live and work. 1 foot still left on my BBQ. Which I have yet to buy a cover for.

We have not seen this since late 1960's according to gov records. Record breaking stuff. Global warming? Not here. That's a scientific debate I like to leave to morons like Al Gore. The planet has been through worse than just us as a species. I post this video here often.

It just makes me laugh as an atheist and what I like to think myself to be, which is a progressive aggressive protagonist of my own life/movie of regression of the species. All I have to do is take a walk outside and gander at mindless ppl not looking at the world outside, even if they are outside. They trip over their own feet while walking and texting. No "hello, how are you today?" It's f off, you are bothering me today in my job which happens to be serving the public, but I am just to damn busy watching this talking cat video to serve you your coffee and maple syrup covered tractor wheel.

I love technology, I use the best stuff. But when I am not at work. I don't own a cell phone. My car does not have GPS, nor does it have a back up camera. I have crank windows. Can figure out north from south by looking at the bark of a tree. Don't need an alarm clock to tell me when to shyte.

All this connected stuff just sounds like prison without bars. Saw an apprentice the other loose his cell phone in the snow, Plow came by, and saw what I thought was supposed to be a young grown man cry like he had just dropped his ice cream on the pavement. What is this world coming to.

Anyway, as usual, off topic, and I have way to many opinions on how Trump is the sole source of my canadian problems when all I need to do is buy a cell phone and melt in with the crowd. Yeah, still not going to happen. My friends and co workers just don't get me. They say I am of little words. Hard to talk to some one when all they do is stare at a 4 inch screen and ignore what you have to say.

I guess that's why I rant here. That way, I get to type to myself all the boring gibberish other ppl think is boring and useless because Trump just tweeted something new to Trudeau or Piong Chang whatcha ma call him..

Found an interesting video on radio shack. Damn I used to love that store. Goes to show what happens when boardroom meets progress.
 
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