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02 Monte Carlo SS 3.8, Intermittent No crank

tunabreath

By tunabreath
in Ask A GM Technician

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gmtech4 Senior Enthusiast

gmtech4

Posted
Posted

Unlike yourself, I am relaxed, not insecure, and not afraid to admit when I'm wrong.

I could research this with a site with nothing but GM techs but I'd rather read your diagnoses for this phenomenon you talk of ,

 

Cuz you say there is no checks for a BCM , and that it inhibits cranking .

 

So explain it to me and get real technical if you need to , I think I can handle it .

SILVER SLED Senior Enthusiast

SILVER SLED

Posted
Posted

I could research this with a site with nothing but GM techs but I'd rather read your diagnoses for this phenomenon you talk of ,

Cuz you say there is no checks for a BCM , and that it inhibits cranking .

So explain it to me and get real technical if you need to , I think I can handle it .

Why do you insist on being so ignorant? You obviously don't know much about cars, so you should stay away from technical threads. Maybe you should stick to who has the best tire shine threads. But for the op's sake mostly, and some what your sake, even though I have no idea what you could possibly do with any knowledge.

 

So, the BCM acts as the main power mode master commanding all the other computers on, and also has some ignition responsibilities also. If the BCM fails, it doesn't set a code, making it hard to detect. There is actually a GM bulletin for such an issue back in the early 2000's. When I get back to work on Monday, I may be able to find it, but it's been so long I doubt it's still in GM's data. Like I said, we replaced a lot of BCM's in our service dept back in those days.

gmtech4 Senior Enthusiast

gmtech4

Posted
Posted

Why do you insist on being so ignorant? You obviously don't know much about cars, so you should stay away from technical threads. Maybe you should stick to who has the best tire shine threads. But for the op's sake mostly, and some what your sake, even though I have no idea what you could possibly do with any knowledge.

So, the BCM acts as the main power mode master commanding all the other computers on, and also has some ignition responsibilities also. If the BCM fails, it doesn't set a code, making it hard to detect. There is actually a GM bulletin for such an issue back in the early 2000's. When I get back to work on Monday, I may be able to find it, but it's been so long I doubt it's still in GM's data. Like I said, we replaced a lot of BCM's in our service dept back in those days.

You are one insulting POS, that's ok , you have no idea who you're talking to , it's called a profile , you should check mine ,

I just want you to show me how you diagnosed this BCM when there are no checks for it , I can check and find the bulletin myself and I don't need to get to work either unlike you ... Rookie , I've been fixing shit since before you were born you arrogant ass ,

 

Just back up your statement , no need to be total dick , talk about Internet mouth , you are a champ pal ,

 

You are a right fighter , you cannot be told otherwise , I just don't believe you , that's allowed here , it's only a GD conversation , why you're being so nasty is weird to me .

 

How long have you been a "guessing tech" ? How many GM courses do you have ,

 

You sir are a classic bully , I'm not going away , just back up your crap ... Tonight !!!!

 

****

SILVER SLED Senior Enthusiast

SILVER SLED

Posted
Posted

You are one insulting POS, that's ok , you have no idea who you're talking to , it's called a profile , you should check mine ,

I just want you to show me how you diagnosed this BCM when there are no checks for it , I can check and find the bulletin myself and I don't need to get to work either unlike you ... Rookie , I've been fixing shit since before you were born you arrogant ass ,

Just back up your statement , no need to be total dick , talk about Internet mouth , you are a champ pal ,

You are a right fighter , you cannot be told otherwise , I just don't believe you , that's allowed here , it's only a GD conversation , why you're being so nasty is weird to me .

How long have you been a "guessing tech" ? How many GM courses do you have ,

You sir are a classic bully , I'm not going away , just back up your crap ... Tonight !!!!

****

I've spoon fed your dumb ass enough. Relax, take a deep breath and stop name calling. Im sure once you look into it, you'll find a more precise and numerous reasons how the BCM can cause a no crank condition and not leave a trace. Your not contributing one bit to this thread. And, if you look you'll see I already did read your profile. I expected better from someone like you. You are the classic example of a "right fighter" ( I actually had to google that, lol). The more you blab the more it shows.

02suburbanZ71 Senior Enthusiast

02suburbanZ71

Posted
Posted

I've spoon fed your dumb ass enough. Relax, take a deep breath and stop name calling. Im sure once you look into it, you'll find a more precise and numerous reasons how the BCM can cause a no crank condition and not leave a trace. Your not contributing one bit to this thread. And, if you look you'll see I already did read your profile. I expected better from someone like you. You are the classic example of a "right fighter" ( I actually had to google that, lol). The more you blab the more it shows.

Govtech4 has been on here much longer than you have so some respect would be appreciated. We don't like it when people cause problems on the site, disrespect like that can get you banned. Also i'm confident rob has much more diagnostic experience than you. I'm not saying anyones right or wrong.

SILVER SLED Senior Enthusiast

SILVER SLED

Posted
Posted

Govtech4 has been on here much longer than you have so some respect would be appreciated. We don't like it when people cause problems on the site, disrespect like that can get you banned. Also i'm confident rob has much more diagnostic experience than you. I'm not saying anyones right or wrong.

He obviously has been on here longer than me. However, he started the name calling and immature, disrespectful verbiage. So if he wants respect from me or anyone else, he shouldn't have to stoop to name calling. Also, I have been around long enough to see these mysterious intermittent no crank MC's and Impalas fixed by replacing the BCM. Nobodies lengthy list of diag experience can change that. No disrespect to you intended. Thanks.

Doug_Scott Senior Enthusiast

Doug_Scott

Posted
Posted

Might have got this thing figured out.

 

I was lucky enough to catch where the spark came from. I found another ground on the trans bell housing. It was a long stud and the nut seemed tight but it actually had a thread or 2 more to go.. It was pretty corroded but not terrible. I took the leads off, cleaned the leads and the mating surface. I started it three times, going to let it sit for a while and see what happens. Thanks to all.

 

 

 

In your original post you mentioned a wire got hot and started to burn insulation, and you commented that it essentially a ground wire. Having the loose ground on the bell housing can cause the electrical system to find the next good ground and use it. Problem is, the starter can draw a burst in excess of 200 amps. If ground is bad, that current has to return to the battery somehow. It is amazing how many times that an odd starting issue goes back to ground connections. There is a good chance for some hidden damage to occur due to some expensive parts. Wheel bearings do not like 200 amps going through them for example. The initial run of the Omni and Horizon model cars back in 77-78 had bad or missing ground straps from the body/chassis to the engine. Depending on how cold it got in the winter where the cars were being used, you may get 2 winters out of a set of front wheel bearings. Factory ground straps were those braided stainless with a slip on clip on each end, similar to the hood ground straps you see on some trucks.

tunabreath New Member

tunabreath

Posted
  • Author
Posted

Yeah, I got lucky by not burning up a PCM, I guess.

 

As for the wheel bearings, we will see what happens. I have heard of wheel bearings failing due to bad grounds.

 

Thanks to all.

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