What has happened now, TTA will barely run!

[tta983]

I has a alternator to go out, showed 11.5 volts while running at alt. I put a new one on and it barely runs now.

The only thing I did was to disconnect the negative battery cable while it was running, I think this was a mistake and it is running like it is running on 2 cylinders, won't idle and won't rev up.

I changed the ecm out and it is still the same. Trying to get a few ideas what might have happened.

 

[1fastcobra]

disconnect the positive cable
Let it sit for a min. Then retry
Posted from the TurboBuick.Com mobile app

 

[charlief1]

The only thing I did was to disconnect the negative battery cable while it was running, I think this was a mistake and it is running like it is running on 2 cylinders, won't idle and won't rev up.

NEVER EVER take a battery cable loose while the engine's running!!!! That creates a voltage spike that will go anywhere! It's very possible that you've spiked the computer or damaged the chip. Do you have a scan tool of some sort so you can check everything out?

 

[tta983]

I tryed another ecm and still the same thing, I will try a different chip and see what happens. Scanmaster shows no bad codes!

 

[RmvBfrFlght]

Likely spiked the ICM. Pull the plug wires off the plugs and stick a spark plug on each one. Place them where they can be seen while reaching in the window and cranking the engine. See if they are all sparking. Note that if you crank it a lot it will flood, so pull the injector fuse(s) if so.

RemoveBeforeFlight

 

[tta983]

I got it running, it was the Chip. I replaced it with a old turbotweak chip I had and it fired right up. Must have been the voltage spike to the chip that took it out. The voltage is really high at the alternator, over 17v. Sounds like the voltage regulator is messed up. So I need to get a new chip burned and need a new alternator! At least it is running now.

 

[Joeld]

good you sorted

i never knew pulling cable could be so problematic although i have never done it and never will after reading this post

joel

 

[charlief1]

i never knew pulling cable could be so problematic although i have never done it and never will after reading this post

joel

When a battery cable is removed while the engine is running it's producing enough power to run the car as well as charge the battery. Once you pull the cable off that extra voltage may adjust but initially it has to go somewhere. On newer (OBD II) cars the battery is what keeps the car running, not the alternator. Think of it like a surge protector for your puter. Once you pull that cable loose you no longer have a surge protector.

 

[tta983]

Got it up and running today, all it needed was a new Alternator and replaced the Maf with a known good one! No problems with the chip or the ecm.

 

[earlbrown]

sounds like you had a bunch of AC ripple coming out of the regulator. When you disconnected the battery, you had nothing standing in the way of the AC to run through the car like a banshee.

 

[tta983]

sounds like you had a bunch of AC ripple coming out of the regulator. When you disconnected the battery, you had nothing standing in the way of the AC to run through the car like a banshee.

I guess since the alternator was not putting out much voltage is made it a little easier on the system, but I am sure that was what took out the Maf. It could have been much worse. Glad I had a spare Maf. And also thanks to Eric from turboweak for telling me about the Maf might be bad.