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HELP! Cranks then Don't Crank

B

Bigboy49251

New member
1999 GRAND PRIX 3.8SC SERIES II 100% STOCK


Hello I need help BAD I am not ignorant when it comes to cars but this really has me stumped here we go. I was accelerating and it just died I had my radio really loud so I couldn't hear if it back fired but couldn't feel anything it just dies as it usually did because of a bad CrankPS but always started back up I let it coast for about 2-3 miles (I was going 70-75) till I could pull in my drive way tried to crank it over it turned for about 20sec NOTHING didn't even try to start then it just STOPS cranking so I think dead battery or starter or wire so I just replaced the battery, ground cable, and starter because it seems easier then driving to bench test and what not but (I had all of them here...lol) still nothing so I pull out the spark plugs and it turns over again (spark plugs are dry) I try some either still dose not start but there is now suction in the throttle body so I take and hold the bypass open thinking it would make it have suction had my buddy turn it over it turns once and STOPS again so I pull just the front spark plus and the are DRENCHED with gas and try to turn it over and nothing just the click I have fuel pressure check them with the nodes and getting good signal what I've come up with is mabye the timing jumped I have spark on all cylinders please help

Thank you for your time and god bless everyone
Brian

P.S. All the electronics work in the car until I turn it to start it when it won't turn...lol it will erase my radio settings too I also have had it hooked to a battery charger as I always do when I am trouble shooting but thank you guys so much for the time I know its kinda scadered I am up to any suggestions besides junking it I am putting a different motor in it on friday evening so I would like to get the trouble shooting down before I junk the motor
 


I would test, or have your battery tested, a weak or damaged battery wont start a motor.

You could also have a issue with your starter, such as a internal problem either draining your battery, or just not engaging. You could have that tested as well for free from any parts store, along with your battery.

Fuel fowled plugs wont spark, so you either need to clean them well, or replace them. This could be a result of it turning over, but not firing, common. Means you have fuel pressure...thats good.

If no spark at all, this could be an ignition problem, such as one, two, or three bad coils. I would see if you have a spark first, and if you don't then look into as to why and work backwards...plug, wire, then the coil. See if its just one plug, or more, and if its more then it could be your ignition control module, the black base your coils sit on. Then you need to see if you have power to that even.

Start with the obvious easy one first, and then test others before you start throwing money at parts you dont need.

One thing to also look into is your engine grounds, that they are clean and tight. The one that can cause a no-start is the little short one that comes right off the negative battery cable, and grounds to the body of the car, under/near the under hood fuse center. You need to be sure this is getting a good ground on every car, ours...usually never cause GM attached it over a painted car. To fix, remove bolt, and sand the wire end clean and shinny, and do the same where it attaches to the body of the car, sand till you hit bare metal, and then add some sort of sealer to keep it from rusting, and reattach the ground to the bod of the car. That much is done now and you can move on, and those who have not cleaned this ground...I'd do it next oil change if I were you.

Let me/us know where this gets you.

~F~
 
I have a good ground both to the motor and the body I've done exactually what you said and I also doubled it with jumper cables going from the battery to the motor the battery is new 1 week old its a red top optima battery I have decent voltage. and on top of that I have it hooked to a battery charger I've even tried starting it with my charger on the start mode 200A.
I have checked the spark as far as the spark plug wires and it have great spark on all cylinders.
The starter I replaced it with was brand new I swapped it out for a new one under warranty about a year ago just to have one lying around.
The main thing that stumps me is how it will turn with no plugs in it but with the spark plugs in it. It cranks about 1 full stroke then it STOPS instantly if someone could help me with this I am pretty sure the rest will just come together pretty simple after that well the basics anyway compression,spark,gas but I have never heard or had this problem with it just stopping like that


Thank you so much for your help GR8racingfool
 
You would get more cranking amps if you hook your battery up to another runing car with jumper cables. If your car is SC you could try pulling the belt off the SC.
 
You stated
"dies as it usually did because of a bad CrankPS"

But I didnt see anywhere that mentioned you replaced the CPS. Was this done? Also, do you have spark on the #1 plug. When you pulled it out did you test for spark and if so what were the results?

I mention this simply because if the CPS goes completely dead, the car wont start. The CPS controls the signal to the Ignition Control Module telling it when to fire and so if it doesnt get the signal, theres no output to the coils and therefore no spark.
 


So it turns over, when there are no plugs in the heads, so you have a "vent" so to say, and when you install plugs it turns over once, then does not turn over at all?

The way I am reading this is that your motor basically seizes on you after one engine rotation, and to get it un stuck, you have to pull the plugs.

Is that correct?

~F~
 
Can you manually turn the engine over with a large ratchet on the balancer bolt? It almost sounds like your starter is bad if it can't crank over the engine because of the compression of the piston at the top of the cylinder.

So the starter just does the "rrrrUUUURRRrrrr"....and then stops? no clicking once it stops turning? The clicking instantly indicates that there is not enough voltage to keep the solenoid engaged, which would lead to checking your battery and grounds...since that's been done, no worries there just yet. If it actually never disengages, that leads me to believe that the starter is bad. Pretty common with "reman" units from an auto parts store. I've had bad dealings with them from friends in the past. They aren't usually re manufactured so much as they are just repaired.

You've got fuel, and you've got spark. Might have to have the starter replaced, or at least bench tested. From the info I'm getting though, I'm leaning toward a bad starter.
 
Okay I have found what happend the timing chain messed up and wasent allowing the exhaust to escape so it compressed the cylinder and the starter didnt have enough power to crank it after that. came concept as vapor locked I though I would let everyone know that incase it happened to them. does anyone know what way is the easiest way to overhaul the motor with or without the tranny? is my quistion usaully I do it without the tranny just curious if anyone could help with that thank you all soo much and god bless you all.

Brian
 


The starter should turn the engine over with compression in the cylinder. That's how it gets things started.

Are you 100% sure that the timing chain is the culprit? It's pretty unusual on a car that is completely stock. Have you pulled the front cover off yet? Turned the engine until the dots line up on the gears?
 
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