$#%^ No Start

ssleeper94

will it run?
I've been trying to chase down my no start for the past two days. I get no spark, I replaced coil,module, cam sensor, crank sensor, swapped computers, still nothing. The car is for the most part stock with a chip. Any ideas on whats causing it?
 
Ehhh, you didn't say anything about fuses, so check that. If not fuses, try VOM'ing the power leads (PNK/BLK) first, then grounds, then sensor leads...

Remember what were you doing when the car last ran? Backtrack from there.
 
Here is something that should be helpful.

"The following was written by Jim Testa and is a very logical means of troubleshooting a no start. Looks like you are ready to begin step 3. Hope Jim's info helps you. It has helped me many a time.
"OK, to diagnose ANY car, you need to find what you have and dont have. The way *I* usually go about it (which might not be right to some people, but its methodical and consistant so I stick to it.

1) Note the check engine light (if EFI). If its not on, STOP and find out why. Listen to how it cranks. I can pick out compression problems doing this. If you are in tune to your car, you can too. Listen to the starter as each cyl comes up on compression stoke. You'll hear the starter slow down a little at that point. You bight hear deerdeerdeerdeer, where a dead cyl m ight sound like deerdeeeeedeerdeer (great sound effects huh?)

2)Depending how accessible the intake is, I'll shoot 3 or 4 seconds of carb cleaner into the plenum. Either thru the throttle body, or the brake booster vacuum port. If its a lack of fuel problem, the car may start, it may simply kick. If it does either, its time to look to fuel system (usually, although enrighening can bring out a low sec output problem too, so dont take my suggestion of fuel as law)

3) If the car kicked, I'll put a FP gauge on it. If fuel pressure isnt in spec, now you need to see why. Fuel pump, filter, resticted line, bad reg, low batt voltage, bad relay, blown fuse etc. If FP is in spec, its time to hook up a noid light and verify our injectors are getting pulsed. If youre not getting a pulse you will want to hook up a scanner and look for RPM during crank. If you are getting RPM signal, check for spark. If you're getting spark and no fuel, although there is a commanded PW (see below) you probably have a bad ECM. How fast it cranks isnt as important as the fact you get a RPM signal. Next you'll look at Coolant temp to see if it coincides with ambient )if the car is cold), and verify TPS isnt shorted to Vref which will put the car in clear flood and cut off fuel. If these all look OK, you'll want to take a look at commanded PW.

3) If the car didnt kick, I'll yank a plug wire and see if I got spark. If I got no spark, then I'll check also for inj pulse using a noid light. If I have neither its usually due to a dead crank sensor. If I have no spark, but I have injector pulse, its usually a module.
Typically:
No start - no spark, has inj pulse -> Module
No start - has spark no inj pulse -> ECM / cam sensor prob
No start - no spark OR inj pulse - crank sensor or module

Oh, and if the module is dead, I suggest putting a coil pack on it as well as most of the module failure are caused by an overheating or arcing coil."


Good luck
 
I'm guessing on thiers a short somewhere, I replaced all those parts yesterday with brand new ones and still nothing, no pulse no spark.
 
Do you get anything when you turn the key?
I had a prob. once with a no start. I would get nothing when I tuned the key. Turned out to be the Factory Alarm Relay way up under the dash. Do you have the Factory Alarm?
Frank
 
Me too (factory alarm). Was messing with the driverside underdash panel when installing my scan master and I tugged on the factor alarm enough to shake loose a wire on the engine bay side of the firewall (fine installation work by the boys at the factory/dealer (basically hooked two wires together with no connector - jeez).

Matt
 
It'll crank all day, but no spark or pulse, the car had an aftermarket alarm but that was disconected before i bought the car.
 
Check your harness inside the car where the ecu plugs in. Make sure they are not corroded or pulled out slightly. Also check the gear on your cam sensor to make sure it still has the pin going through it. Also check inside the cam sensor hole to make sure nothing could have snapped in there. Lastly make sure that your crank sensor is going through the proper groove. Which is between the 1st and 2nd groove from the opposite side of the plug in. If everything checks out thus far electrical wise then you gotta pull the front cover and see if anything snapped in there.
 
I checked cam and crank sensor, i'm going through the no start diagnosis on the vortexbuick-etc site and I noticed that the blue wire into the cam sensor was corroded and came apart from the connector and was only puting out 5volts as for the 6-9 its supposed to put out. I"m going to check for an open cirucit on that wire next.
 
the bolt behind the pass head on the firewall, should be 3 pairs of cables.

The ground strecher kit is the best route and its cheap , if you order it today caspers can have to you tomorrow.

I created 9 ground points on mine, a little too excessive but better safe than sorry .
 
This is kinda obvious and I may sound kinda silly, but I had the same problem with my IROC before I bought this buick of mine.

Turned out the fuse from the "hot" battery cable to the ECM had totally rotted away along with its holder. ECM has NO power to it at all! Bought a new one at the local parts store and was up n runnin in a half hour or so .... just a thought....

Iuno know if its even worth $.02 but there ya go! :D good luck ... keep us updated when u solve the problem.
 
Good news and Bad news

I got it running today, I ended up trying another crank sensor I had laying around, i got it to start up but now i can't keep it running. I tried playing with the cam sensor but it keeps missing and backfiring. It has new plugs and wires. I'm this close to bringing it in. Any ideas on the misfires
 
Congrats your almost there!


Check the ignition to coil pack wiring, if you have one wire off it will backfire and miss really hard, or just put your old working one back on.

myles
 
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