FrankSS

iTrader: (18)

hey guys... my lt1 project i have is messing up. it has been sitting for about a month, and i went to start it today and it was running all crazy. it would fire up, but the tach would not be reading. then all of a sudden it will die.
after that, i would turn the key on and they tack will do a crazy little dance then settle down. i try to start it, and it sounds like it is firing 180* off. it will go back and forth between those 2 things randomly... any thoughts? only thing i can think of is get another ecu. TIA

FrankSS

iTrader: (18)

i also posted this in PCM and Diag...

96capricemgr

iTrader: (1)

Of all the times I have seen people claim "bad pcms" it has actually been very rare it was the pcm.

Number one suspect in all electric wackyness has to be grounds start by checking those.

Smokinlt1

^^^I'd have to agree on this. Sound like a bad ground. In the last 7 years as a tech I've only seen a pcm replacement fix the problem twice. Both times they were on Crapallacs.

Jditlfm

iTrader: (26)

Check bat voltage as a number 1. How are the plug wires double check them also.

xx_ED_xx

iTrader: (17)

codes?

FrankSS

iTrader: (18)

it has a new battery in it, but was drained pretty low trying to get it to start. plug wires are all good... double and triple checked them. i still have to hook up a scanner to it to see what kind of codes it is throwing.

but will a bad ground allow it to run occasionally? also i can start it up and the tach wont be working.... i hold the rpm at around 3k, and then it will just shut off or it will go down to idle and barely run sounding like it is firing 180* off

RoAdRaGe912

As stated the first thing you need to do is check battery voltage. Charge it up anyway if it's been sitting for a month. If this isn't your problem then move on to something else.