Thanks greg for doing that! I've already checked the transaxle ground and it's good. I need to check the 5 volt references and grounds from pcm to sensors bit still figuring out exactly how to do this. My guess is either I have a short in the harness or the pcm is screwed. I bought a multi meter already so now all I need to do is figure out the correct way of metering everything.

If turbo monte don't soon start being good to me I'm gonna give her divorce papers I've had enough

One thing I need to know from someone is how many ground wires are on that trans axle stud? I have 2 there but wondering if I'm missing one and there should be 3.... (unlikely I would do this but possible)

 

Anyone? How many ground wires on trans axle stud?

Also can anyone assist me on how to meter these wires to check for 5volts, constant power, good ground?

 

Hey John, sorry have not been here in a couple of days. I'm not able to answer this as you would suspect. I did however copy and paste your questions and send to Matt, hopefully he will answer today. Usually pretty fast in responding to me.

 

Ok sounds good man. I know there is people here with wiring knowledge that probably knows but I guess they haven't clicked my thread to read lol

O well hopefully Matt can she'd some light for me and if not I'm sure I'll figure it out on my own lol

 

Heres a thought...
As we all know Tadd recently had a Ground issue on his...

Maybe you should check out the chassis ground that runs from the negative side of the battery to the chassis... (its a 2ndary chasiss ground)
He found that the threads were actually rusted...thus causing a non connection for power to the whole car...

Maybe...
Its lacking a "Good" ground and this could be a sign of that happening...?
Just a thought..

 

I am Def going to check that it's on my list lol. I'm trying to figure out where all of the grounds are though. I know one by battery one on trans and one on coil pack bracket. Just not sure if there is any others and how many grounds are on the trans

 

Hello John , here is Matt's input on how to do a couple of things. Hope this helps bro...

Greg: the connector on the stud is one eyelet for the pcm grounds and one eyelet for the negative battery cable. I think there are two wires coming to the one eyelet. To check the system for good ground, 5v and return to the pcm needs to be done with voltage drops. First do the ground to the tps, using a test light, hook the alligator clip on the battery positive and touch the stud to the ground connector of the unplugged tps, the light should light. While the light is lit take a volt meter take one lead and place it on the negative battery cable, place the other lead on the pick of the test light, the volt meter will read the voltage drop in the ground system, this must be under 0.5 volts. Check the 5v supply to the tps with the problem acting up, back probe (do not pierce the wire, use a paper clip or t-pin pushed backwards into the connector body) the 5v wire (gray) with the connector plugged into the tps, volt meter measuring the back probed wire, black lead on the battery negative, the volt meter should read very close to 5v. To measure the signal wire (blue) back probe both the pcm (c2 #66) and the tps hook one of each leads to both back probes, the volt meter will read the volt drop, with the problem acting up this must be very small (I like to see under .05 v). I would also check the pcm grounds and powers using the voltage drop method, with one exception, instead of a test light use a headlight, those wires handle a bunch more current so the headlight helps to simulate real use conditions. Hope this helps.



Thanks,

Matt

Matt Snell
Paul's Automotive and 4x4 inc.
48 E 9400 S
Sandy, Ut. 84070
801-255-7472

 

Thanks greg! As soon as I get a chance I will be running these tests!!

 

ok on my map sensor the voltage was reading low so i swapped pcm and map was better. at the time of tests the tps wasnt acting up so couldnt find any issue there.

i used dhp to write my spare pcm with my current tune and changed vin number etc but dhp or tiny tuner wont let my change the serial id number so i cant tune my spare pcm with hpt now unless i buy credits unless someone can terll me how to change the serial id number in the pcm.

since dhp left me burn my current tune i could drive the car. went for about a 30min drive and had no tps issues or fuel level issues. no tdc were thrown for anything either. as of now so far so good looks like the pcm was bad. i am going to take it out tomorrow and put some miles on it and see if the issue happens at all and if it doesnt i am going to say the pcm was the issue.... i might swap the (i think junk as of right now anyway) pcm back in if the issues dont happen tomorrow on the spare pcm after driving for a while and see if the issues come back which would finalize the pcm as a failure if the issues come back.

any other thoughts from you guys?

anyone know how to change the vcm serial id number with either dhp or tiny tuner to save me from having to buy credits to unlock my spare pcm so i can tune with hpt?

i found in tiny tuner where i should be able to change the serial id number but when i change the number tiny tuner wont let me save it. dhp i found where i can change the vin but not the serial id number.

on the other note i hit 11psi, was rich, no knock, was spraying meth, maxed out the maf at 53% throttle, and was pulling like no other with tons of power!!! breaking tires loose like no other!!!

it needs tuned for meth, BAP, the maf scaled mack even more with the afc, maf tune, timing advanced, and turn up the booooooooooost!!!! this will all be done on the dyno this coming saturday though as long as the 5 volt reference issue dont come back to haunt me again