I have some big voltage problems after my TPI swap..I swaped from carburettor Lg4 to TPI on a 87 Camaro..305 Engine...

There is something that is affecting my voltage inside the car. My voltmeter in the dashboard gauges is going VERY much up and down...From 13volts down to 8 volts...Jumps up and down and have more troubles if I turn lights etc etc on....I think something is stealing the power, but what and where could that possible be??

I have checked voltage at the battery, alternator and many many places around the engine..Everything seems fine there...about 12.3 to 12.5 when engine is off..As soon as I start the engine it jumps up to 14 volts...sometimes 14.2 and so on..
So that means that the alternator is working.

But still I have those low volts on the voltmeter on the car...I know many of you guys now will say. The voltmeter can be broken, but I can promise that it isn't. Because when the voltmeter drops like i say. my idle on the car is getting very low and is much controlled by the volts...Another thing is that I get codes like 21 and 22...and 34...That is because of the voltage again...

I have also tried to measure some of the wiring that goes to the fuse panel under the dash and there I get about 13volts when engine is running....Is that normal or should it be more??

Here is a movie clip that shows how the voltmeter acts. Sorry my english accent.
http://www.youtube.com/watch?v=N2-gVeeRFFQ

Any ideas of what this could be??..Hope to get some hints from you...

 

Not anybody that have an idea????anybody???

 

WHEN are you losing the volts? (ie..when your running the Heater Fan, Rear Defrost, Power Windows, Radio, etc.) Keep an eye on your gauge as your turning on your options and you should be able to "see" what is causing the most drain. I'm having the same type of problem in my 86 Sport but I've narrowed it down to my Rear Defrost as I have been watching the volt meter when I use anything that draws current. When I use my Rear Defrost the volts drain from 14 to 9 at idle!! (That's the important time since if your alt is strong, as mine is, It'll show good when under throttle...still 13+ volts) I'm pretty sure that on mine, one or both of the power wires is "grounding out" and causing the drain since I've already checked the grounds. Find out what is showing the most pull and you'll probably find your problem. Hope this helps!!

 

You'll want to have a look at a wiring diagram. There are several thick red wires coming off the starter and going into the car (through the C100 bulkhead/firewall connector). One of the wires feeds ignition circuits and another feeds lighting ciruits etc. Check the connections & the fusible links at the starter first, then try with disconnecting and reconnecting the C100 connector. I guess the latter can be a pain in the *** procedure..

 

all i can think of is check the grounds.

 

Yeah I have been looking on a lot of diagrams of that year...One of my problems is that I don't have a C100 diagram of 1988...Because my TPI wiring harness is from a 1988 TPI Camaro and my Camaro is a stock 1987.
The only wire I have changed at the C100 connector is the fuel pump...that was on another pinout...I have C100 diagram for 1987 and for 1989 but nobody have someone for 1988...

When it comes to the lightning harness there is no changes at all..That is completely the same as it was when it was stock 87 carbed engine..
The lights at the C100 connector is a own "connector" that has not been changed..Only the main piece have been changed...

Do you think that because of the wiring is unable to tighten at the starter solenoid, could affect anything?..Because those threads at that solenoid are made of copper and that material is veeeery soft..So one time when I was going to tighten it I tighten it a little bit unstraight so the threads where damaged...And to fix those I need to buy a new solenoid...

 

Found out something today..I have tried to measure all of the wiring at the C100 connector from inside the car..Especially the wiring that goes to the power distribution....I can only get about 12.8volts on that one when car is running...Could this be that the alternator is not giving enough power (Ampere) to the car???

Or could this be that the power distribution is coming from the starter solenoid at the starter motor..And there is not tighted to much because of the threads?...could that affect anything??...

 

Found out today what the problem was so now my car is charging perfect.
I am a little embarrased because of the mistake but you guys know how it is when wiring up those engines...one wire here and there..

The problem was one of the main wires that goes from the + on the battery and down to the starter motor...It was actually not connected to the starter so that means there was to little wiring going in to the car...

Now I am happy so far...But thanks to all of you that have helped me out.