No start condition need help

87chrisss

BLUBYU
Joined
Jan 31, 2011
Ok, let me start off by saying i know my way around these car's fairly well but i have reached a dead end on this car.

I bought this car on here and its given me nothing but headaches, i bought a new crate motor for it finally got around to installing it all came out nice, the bummer is the car wont start, intermittent to no spark. Please dont post a link to vortex buick i have read the no start condition multiple times. This goes beyond the no start tree..

For the breakdown,

Has injector pulse but no spark she seems to get intermittent spark. I have swapped around ign modules to a verified module that works on my other car.

Has fuel pressure and inj pulse.

Verified cam sensor timing already with cam sensor tool, Even swapped out for a known good cam sensor from my other car.

Changed the crank sensor twice for shits and giggles even though i had injector pulse i still swapped it out.

I have verified voltage on ign module bulkhead to all pins/circuits.

Verified Signal and Constant on Cam sensor and Crank Sensor, I checked crank sensor clearance

I checked voltage at ECM plugs as well for hi low crank sign and cam signal.

Out of a miracle while just cranking it over, she decided to turn on for a quick second and then cut off.

What am i missing.. could the ignition switch cause this? My buddy keeps telling me to check ignition switch i just don't see how it could be ign switch?

It seems to intermittently have spark. I'm checking for spark with a flathead on the boot and close to ground i crank it over with no visible signs of spark.

Im at a dead end been 2 days diagnosing this for over 20 hrs. taken apart and put back together to many times..

Grounds are good. No blown fuses. Checked all fuses, All are good.

Swapped computers still same issue, Also just fyi i did have the new battery on a charger 13.99+ volts at all time. Im at a dead end. For some reason it seems when we wiggled the ignition switch and turned it over a little rough it seems it turned on for a sec..?! I dont see any shorts or splices anywhere other than the knock sensor on ECM??? I also swapped ESC modules for possible faulty esc module nada
Harness looks decent only thing is cut is the original 3 wire oil pressure switch which was swapped out for a electrical type oil pressure gauge. I tapped them up and are out of the way FP/Inj fuse is fine so i know there isnt a short with them...

What am i missing? What should i try?

I bought the car non driveable, car was parked i would say for easily 5 +yrs. I was told only a few months but when i got into it it was easy to see it was way longer than that. Replaced fuel lines gas tank fuel pump/hanger just the works you already know. Car was obviously parked for something and im going to fix it with your help..
 
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I'll answer myself lol,

Im going to try a new ignition switch, after reading my own thread i think the switch might be the culprit of this intermittent no start issue.
 
Chris, did u change the cam sensor cap when u changed the cam sensor? I went through the same problem. The car would sometimes run for a fee seconds and die. Sometimes it would try to start the explode out the exhaust. Fouled out 3-4 sets of plugs! Finally wiggled the wires around on the cap right where they go into the cap and it fired! Come to find out the wires were broken inside the insulation and would make contact occasionally. I could have sworn that i had changed both caps but i may not have. Put a new cap on and it fired immediately. Pealed the cover off the wire and the wire was completely broken but must have made contact once in a while. Just got lucky to find the problem after a week of pulling my hair out and pulling and inspecting my $650 wiring harness three times . Plus all the things u did.! Double check the cam sensor wires and connections !!! Good luck.


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Go over all the pins in the module female connector with a small pick. Bend them just a little to give better contact at the module.
 
Thanks guys what do you think about the ignition switch i have never had one go bad.. Not sure if it would give some of the symptoms I'm coming across Don't want to throw parts at this car anymore.

Brian, the pin thing is a good idea, i might as well try to get the female connectors a bit tighter so they make better contact..

Ive also looked for kill switches or an old alarm but nothing. I honestly think if it were the ign switch it wouldn't even turn the starter or turn on all the lights and SES in the first place..

Does anyone have a ignition switch wiring diagram/schematic.. Would like to see how the ignition switch could effect spark timing or ICM.

Everything that requires power on the ICM female bulkhead has power. So it leaves me with cam and crank sync for icm to send spark signal..

(im typing outloud) better thought process.. Bad ground, ?! i checked all the grounds.. Behind passenger head.. front of passenger side , firewall strap to engine..

Does anyone run a seperate ground to ICM? I did check the nuts that hold ICM to bracket they were tight..

I'm receiving proper voltage @ plugs for both cam and crank sensors, 10+ V & Signal voltage is also apparent. What can prevent cam and crank sync @ ign module we are talking about 2 verified good ones that we tested on my other car within minutes,?!
 
Following. I know that feel, bro. Got a hard start (damn near no start on some mornings) that I just cannot figure out. Did you check the three bolts under the ignition module that mounts to the bracket? No spark at plugs, or no spark at wires?
 
Harness looks decent only thing is cut is the original 3 wire oil pressure switch which was swapped out for a electrical type oil pressure gauge

Do you have the oil pressure switch that was cut? can you put it back on? Just a thought,use it or ignore it it's all the same.

Was there an engine in the car when you bought it? and if so are the injectors you are using out of that engine? stock chip
 
Here is a diagram of the CCCI that you requested. If I understand correctly you bought this car and it never ran. Is it possible this car has some sort of antitheft either in the chip or someone's creative approach with wiring inside the car? Hope you get it figured out but if you need additional stuff from the factory manual just ask.

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I have not checked the fuseable links, Good diagram i have multiple Service/shop Manuals for our cars, what im interested in is if anyone might know the schematic to the Ignition switch*

Rick, move the cam sensor like if it might possibly be 180* out? Wouldnt it still turn on just run rough?

I set the cam sensor as usual 25* atdc, #1 piston on top. Set cam sensor window facing driver side headlight dot on the gear facing passenger side, turn clockwise 1/2 a turn the turned counter clockwise till light on the cam sensor tool turns on lock it down.
Checked reluctor ring even changed the cam sensor to a new one i had with no play at all. Cap is new as well.

I did not manually check the cap with a screwdriver trick but if its reading thru the cam sensor tool should be fine?

That is another thing where does the cam sensor get its power from ECM then to ICM? or ECM give power to ICM then the cam sensor gets power from there?

I might sound a little funky in the morning too early to think
 
Not 180 out. Just move it a little and see if it starts.

The cam and crank sensor get power from the icm.

Rick
 
Won't hurt to try.. ill try both ways, CW and CCW i guess,
For sure it was parked for a reason, then i have to come along and pick up a headache that no one could fix.
 
Unplug the injector harness and plug it back in while cranking. You will need a helper. Make sure the correct window is used on the crank sensor. Bypass the factory wires and hot wire the module after making site the connection is good
 
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Since there is injector pulses the ICM is getting the cam & crank sensor signals. The ICM sends the reference pulses to the ECM which in turn fires the injectors.

With the injectors working and a lack of spark, check pin M on the ICM. Note in the CCCI diagram how pin M feeds power to the coils, and has a separate power feed from the CCCI fuse.

Pin P on the ICM is getting power as that powers up the ICM, which powers the cam & crank sensors, along with sending the reference pulses to the ECM.

No power to pin M on the ICM is going to be the issue causing the no-spark.

RemoveBeforeFlight
 
yes i checked Pin M , here's a dumb question am i supposed to check the voltage on each pin while connected to the ICM? Or unplugged from ICM? Or either or doesnt matter same values should be present?
 
It is best to check power with a load on the source. Lift the coil pack up and connect the DVM to the blue wire that feeds all three coils. Leave the wire connected to the coils. Now key-on, engine-off and check for +12 volts (battery level). Now crank the engine while observing the DVM, make sure that the power is still there while cranking.

RemoveBeforeFlight
 
I will have my frend come over tonight and help me out, i cant read values on a multimeter and turn the engine over thru the ignition in car. I can read the values while ignition on but no way of me verifying the values while its turning over. I should install a bump button. Would values differ while cranking? that might show some type of drop or inconsistency in voltage to ICM pin M?
 
Set the DVM in the hood/wiper area to see it while reaching in (open window) and cranking the engine over.

The voltage at the blue coil wire will be lower when cranking. Usually in the 9 - 10 volt area.

RemoveBeforeFlight

LOL, and we just posted again at the same time.
 
Sorry to ask so much junk im just trying to rule out inconsistent rdgs,

These values are present while connected to ICM and wire backprobed or will they also be apparent on ICM bulkhead unplugged, because i have tried both i would prefer to get the reading from the female pin on the bulkhead without it being installed, thats whats making contact...

The ICM i know for certain isnt the culprit. I tested her on my other car minutes apart.
 
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