Urambo Tauro

I don't have any pics of the grounds to share at this moment, but here's a list of ground points for 1995 models:

threehourshower

Ah man I guess I'm too new to download that, the forum won't let me. Can you post it on some other photo hosting site?

Urambo Tauro

Here, this is the list of engine compartment ground points:

threehourshower

I am getting under the mustang's hood soon, but I have a question before I do.. The battery gauge is barely a quarter of the way up when I turn the key but dont start it. Had advance auto test yesterday and they said battery tested ok. I'm in Texas, can my battery somehow test good if it's earlier in the morning before the heat really hits? Or is it more likely a ground? I probably need to hit it with a multimeter myself for peace of mind, but I just moved and it's all packed away in a box somewhere.

threehourshower

So Ive tested the alternator myself, over 14v while running. The battery tests out at 12.6 while the car is off. I cleaned up all the wires and grounds I could see, although I cant find where the largest gauge ground wire from the battery terminal bolts up. Maybe I should just run another right next to it and ground it to the chassis?? I do know you cant have too many grounds. There still seems to be quite a bit of fluctuation in the gauge, especially during the warmer parts of the day. If it reads correctly, voltage drops all the way down to about 10v, maybe less, when its hot. Since it feels more erratic than constant, I am still compelled to believe it has to do with the electrical system somehow. Its hard to get a good visual angle on the starter to see those connections, but everything else is certainly solid. Probably the starter too, The car was in the shop about a month ago for a 30 point inspection, upon which the mechanic said the only things requiring some attention were a small leak in the timing cover gasket and the MAF sensor (which I had them go ahead and replace already.) With new plugs, wires, ignition coil, 130a alternator, and a pretty damn clean MSD cap and rotor, Im running out of ideas for a possible culprit in this mystery case.

threehourshower

Little update, I've checked all the grounds, replaced the battery, and still scratching my head. Problem persists. I have full alt voltage when the car first starts, then it lowers as the motor warms up. A buddy says he thinks my pcm is going out. Can anybody confirm that as a possibility?

Urambo Tauro

Maybe as a last resort for the original misfiring problem, but it wouldn't explain the charging issue. And PCMs don't fail often enough on these cars to warrant immediate suspicion.

When you checked cables and connections, did you check them all the way to the alternator too? If so, the problem sounds like it's in the alternator, possibly the voltage regulator.

drmambo31

Hi, everyone, new mustang owner. well not that new, I had my mustang for over a year now. my car was riding smooth and felt the power. I installed a CAI and cat back exhaust. the car was running nice and smooth with a small increase in power since have not tune the car yet. I was using premium gas from a gas station close home. then 2 month ago I changed to Costco gas. yesterday I noticed pipes are black. I checked my oil, water, seals, everything and nothing wrong. but this is concerning because never happened to me. there is any possibility that changing gas station can cause this. I have never see any black smoke when I ride the car or stop at a traffic light. also I have noticed the car feels less power and with intermittent flash of strong acceleration. I would change the oil, even I have 2k miles left on the current one. my car only has 57k miles and then only thing a changed was the water pump. also if any of you can advice about BAMA tune, I want to go for it but need some advice too. any recommendations?

wbrockstar

Black smoke is usually indicative of an engine running way too rich.The excess fuel doesn't get burned,so it creates smoke.If a vacuum leak is present,the unmetered air will enter the exhaust after its passed through the engine & the o2 sensors will measure it and trigger a lean condition.When this happens,the ecm will add fuel to try and compensate for the lean condition,but it does this falsely because the engine really didn't need extra fuel to begin with.When too much fuel is added,black smoke will begin coming out.Another thing that'll cause
black smoke is a ruptured diaphragm
on the fuel pressure regulator.It allows fuel to be sucked in to the engine through the fpr to intake vacuum hose,
dumping raw fuel in to the engine.You
can check for this condition by letting the engine idle while you remove the fpr vacuum hose.If fuel is seeping out of the regulator port or the vacuum hose has fuel inside of it,the regulator is bad.You didn't list your year model,so if you've got a 86-88 model with a map sensor or 89-95 model with a bp sensor,that sensor can cause your symptoms too.A dirty/defective maf sensor will also cause it.If you check the things mentioned in the posts above and they all pass,the ecm should be removed from the kick panel and inspected.If the ecm is responsible for the rich/black smoke condition,one/all three of the bluish green capacitors on the ecm circuit board are usually bad.Their posts can be broken off or eroded by the acid that leaks out or the cap can be bulging.The signal return trace on the board could also be open.
Have you ran koeo/koer tests yet?? If no,do that first and post any codes you get. A jumper wire and the check engine light is all you need.