98 3.8L cranks but wont start

[luminachick]

At the suggestion of tblake, i'm starting a new thread for this.
I have a 98 lumina ltz with almost 150k mi, and a history of a delay in initiation of the starting cycle; when you turn the key, there is sometimes a brief hesitiation before the engine cranks. At various times, I have replaced the plugs, wires, the starter, alternator, and a few batteries. It also has this oddity that i think is unrelated, of not lighting up any brake lights except the highmount unless you pull back slightly on the turn signal.
A few days ago, when starting it up in the am, it hesitated briefly before cranking, then had an unusual rough idle that persisited until I shut it off. The next time i started it up, the hesitation was slightly longer, and the rough idle was present again. Also that time, the security light stayed on. After filling it up at the gas station with it running because i was afraid it wouldn't start back up if i turned it off, i proceeded down the highway. While on the highway, at approx 50mph on a slightly downhill slope, the engine misfired, and a second later stalled out entirely. While coasting in neutral, I tried to start it again, and at first there was no response, but after a few tries it would crank but not start. After getting it towed home, I discovered a blown serpentine belt. After replacing that, there was no change. The car still would crank but not start. First I checked all relevant fuses and relays. The fuel pump relay is heard to engage, as well as the fuel pump itself. Fuel is getting to the fuel rail. I'm thinking it's not the fuel filter or pump because of this. An ignition tester at the plug revealed no spark is being produced. It also appears there is also no current getting to the fuel injectors, as there was no reading on a voltmeter in the electrical connector off the fuel rail. My guess right now is the PCM. Anyone know where it's at, or have any other suggestions?
-tblake suggested:
yes, try a different key. if the security light is on, the VATS system
will disable current to the fuel inectors and to the starter relay.
Instead of looking into an ecm related issue, first check out the
condition of the resistor pellet chip in the key, and the contacts for it in
the lock cylinder.


-i have already tried two different keys. and i'll try cleaning the contacts in the cylinder just for kicks, but i'm not sure if that would've made it misfire and stall. but if that IS the problem, is there any reset needed after the contacts have been cleaned?

[tblake]

no reset needed. Lets recap here, you get in the car, turn the key to start, and crank but no fire, or no crank? Or? And if it is cranking, are you lot getting fuel or spark? Is your security light still on? And btw, the brake lights are routed through your "multifunction switch", and these have a high fail rate. Soon you will have no brake lights alltogether, and will need to replace it.

[Blue Bowtie]

Sounds like it's time to check out the VATS.

[richtazz]

I have a 98 lumina ltz with almost 150k mi, and a history of a delay in initiation of the starting cycle; when you turn the key, there is sometimes a brief hesitiation before the engine cranks.

By this, do you mean that you turn the key and nothing happens for a second or two, then the starter begins turning, or do you mean that it cranks for a few seconds before the engine fires?

[luminachick]

in response to tblake:
turn the key, crank but no fire. not getting spark or power to FI. Fuel squirts out from the fuel rail when you take the cap off. i don't know if the security light is still on because it will only register after the car is running and goes thru the system check.

in response to ricktazz:
i mean you turn the key and nothing happens for a second, then the starter kicks in

[tblake]

sounds like the vats system isn't working correctly. Well, i could tell you how to disable it permentaly or temporarily. At any rate you can either eliminate or confirm part of the system as the problem. It involves soldering skills and a multimeter is required. As well as access to a radio shack.

[richtazz]

I agree with tblake, it sounds like a vats/security issue. You don't by chance have an aftermarket/add-on type of alarm/remote start on your car do you?

[luminachick]

gave up and had a mechanic friend work on it. camshaft sensor. thank you everyone for your help.

[Blue Bowtie]

AFAIK, even with a failed CMP, the PCM will eventually fire the injectors in batch mode based on the CKP. You might not get ignition, but should have had injector pulses. This is a BUick 231, right?

I could be mistaken, however.

[luminachick]

all i know is w/ the camshaft pos sensor replaced, it is starting again. security light has not come on again. btw, blue bowtie, it's a 3.8 chev lumina. from what i know, the camshaft sensor senses TDC (top dead center) so that the FI fires at the proper time. what i dont know is if there is a failsafe that shuts down something, maybe the PCM, if there is no response from the camshaft sensor. one thing i found puzzling is that no diagnositic codes were present. but anyhow, thanks everyone.