LMM: LMM Attempts Crank but wont. Think VATS or *83 OS. HELP!

[SIKDMAX]

Hey guys, long time noooooo see. Lots of excuses, none very good haha.

Anyway, I buttoned up my truck today. No, its still not running. Everything in my opinion is taken care of except for a tune. Problem is, it wont start.

Ive eliminated 1 battery and am running a single in a frame mount. Another "shop" did some work on it and did some hack electrical - I think I have all that sorted out. Ive checked fuses, relays, the MEGAFUSEs on the firewall, all good.

I thought VATS.... but then I came across the TSB on the *83 LMM OS, and it doing a no start until a new OS was put in.... *9something.

What exactly would it do when it doesnt start? My truck clicks like the solenoid for the starter coming on, and it moves the belt maybe 3 inches.... like one application of the starter. It seems to me electronic.... something is not allowing it to start.

So, does this seem consistent with that issue? I have my tune I can email to someone if they can script it over to the new OS... I dont think I want to try with not having touched EFI for 2 years.

Thoughts?

 

[gmduramax]

That doesn't sound like VATS or the TSB. You sure all the wires going to the solenoid, starter are good?

 

[rcr1978]

You said that 1 battery was eliminated? I'm assuming its the passsenger one? Anyways the large main ground wire on the passenger battery there is another smaller wire tied into it right at the battery lug, my old truck would not start unless that wire was grounded properly. Only reason I say this is because I had a problem with a bad crimp on the negative cable and without a good connection on the smaller wire my 07.5 that did exactly what you say yours is doing I soldered mine and the problem was fixed.

Probably not the problem but a place to look, good luck.

 

[SIKDMAX]

I know which ground you are talking about - yes what I did was take the big negative going to the passenger along with that small ground and terminate them to a ring terminal and into a bolt on the frame. Maybe I should check that for a good ground.

 

[rcr1978]

12617083 was the bad OS and you can upgrade with EFI live to fix the problem I did it on one of the service trucks at my old work. However it would not even attempt to start and it had a couple of codes dont remember wich but incorrect immobilizer key sounds familiar. I upgraded that truck using efi to the 12628594 OS and the problem was fixed. Basicaly full flashing the newer os gets all the updates in except for a couple of transmission ones but fixes the no start problem.

I mentioned this because you mentioned that TSB but I doubt thats whats wrong with yours sinces it attempts to spin over, does the display on the dash go blank when this happens thats what mine did in addition to what yours does due to the bad connection on that small ground wire.

 

[SIKDMAX]

Yup, dash goes blank, resets EFI if plugged in, etc. Like kills all power for a second as if it was cranking. I guess Im going to have to unwrap the wiring I did and maybe take a jumper cable and clamp them directly and go to the battery and see if that does it.

 

[duratothemax]

you have a loose connection/bad ground somewhere....

its not a VATS issue.

ben

 

[SIKDMAX]

Thanks..... I will continue checking. What a nightmare.

Do our trucks have sufficient frame to engine to negative terminal connection? I know this would be the "big 3".... I take it I should perform the "big 3 upgrade"?

 

[duratothemax]

Thanks..... I will continue checking. What a nightmare.

Do our trucks have sufficient frame to engine to negative terminal connection? I know this would be the "big 3".... I take it I should perform the "big 3 upgrade"?

Yes.....of course they do.

I dont have any fancy expensive upgraded wiring and my truck starts just fine on ONE battery in -10* winter temps without being plugged in.

Did you forget to reattach the ground strap that goes from the driver side head to the firewall?

And ALL the grounds on the bottom of the block? Theres about 4 of them IIRC.

ben

 

[duratothemax]

Is the rear engine cover painted? Maybe the starter isnt grounding properly through the paint.

 

[SIKDMAX]

No rear cover paint. The truck has ran before just fine on 2 batts, this has to do with the 1 battery conversion. Everything points to that front ground. Good to know that Im not missing any - the 1 large 4 gauge and 1 smaller approx 10 gauge, correct racr?

Im going to remove them, check the crimps, and wire brush all the areas and try again. Had to run some errands earlier.

My daily driver... damn Ford.... lost its Trans yesterday - so Im currently vehicleless - that was the final motivation to finish my truck :spit:

 

[JoshH]

Maybe you should put the ground back on the block and see if that fixes anything.

 

[SIKDMAX]

Back there? This ground came from the 2nd battery negative terminal.

 

[MMLMM]

How long has it sat? Could be a bad battery. That's common lately in every issue seems like I have been dealing with lately. Try swapping out with a good known battery. It's an easy test anyway. Maybe also try that battery in the truck you swap with for a better test. Worth a shot. Doesn't sound like vats to me. How ever go to the 94 os because you will get the vats issue at some point and may not have efi with you.

 

[ripmf666]

Matt if I read what you did right. You did away with the driver side battery and your only running the pass side down under the body side. And your only using the cables from the 2nd battery for power supply and ground. I have found that when running 1 battery you need the driver side leads hooked up for power supply and ground to work. Doesnt matter is the pass side ground is used. My pass side power and ground wires are taped over and zip tied away. I know when I have the trans out of my truck I need to put the windows up and had both batterys unhooked. tried hooking up just the pass side and that did not work also would not turn the dash lights on or anything. unhooked that and hooked driver side up and everything worked its worth a try for you.

 

[MMLMM]

Good point. Driver side connections need to be getting the juice. Truck will run and start with pass side battery out, but not other way around iirc.

 

[rcr1978]

Thats kinda weird that some trucks wont start with the driver battery unhooked. The truck I was chasing this same problem on would start on one battery either side . I disconnected both numerous times trying to find my problem trying to isolate one or the other as a bad battery. Mine was so intermittent it never did it while I was trying to fix it only when I was trying to go somewhere Eventualy I noticed that the small wire on the negative passenger cable was getting pretty warm, I trace that wire down to the frame behind the bumper somewhere dont remember exactly where but if unhooked I could duplicated the problem when hooked up everything was fine. So I soldered the battery cable and never had another problem. Maybe try checking where that wire terminates on the frame, I think there was 2 others right where it terminates could be one of those two.

 

[JoshH]

Back there? This ground came from the 2nd battery negative terminal.

Sorry, I misuderstood. I thought you were saying you took the ground coming from the battery to the block and the wire that bolts in with it, crimped them together, and moved them to the frame.

 

[SIKDMAX]

Gotcha.

The drivers side battery is hooked up with the driver side connectors (extended) under the driver side frame mid cab.

The passenger side battery has been removed. The positive lead had its terminal cut off, and the 2 ends of the wire joined. The ground was terminated to ground. Im thinking it just has a bad connection. Going to get out there this morning and get goin on it. Need to put a tire on one of the motorcycles first so I have SOME transportation.

 

[MMLMM]

ok gottcha now. try post 14 again lol