Ive been letting some issues fall by the way side these last few years and now that my FC is my daily again I need to fix them. Some background of the car: Chassis S4, ECU Haltech Sprint, Drivetain s5, Alternator s5.

When I start the car the voltage is low like 10volts then I rev it to 2100rpm-ish and i hear a click from I assume to be a relay and the voltage then reads 12.5. This in more than just the dash gauge reading... the car's electronics: lights, fuel pump(which i can hear become louder) etc. bump up due to the increased voltage. This happens every time the car sits for more than a few minutes.

Next the alternator is pumping out 13.5 volts when im driving Im pretty sure thats not right. I think its what killed my coil packs. I followed the wiring diagram for s4 to s5 alt except for the wire to the gauge which I dont know which is which on the trans harness. but I connected the yellow wire to the battery.

During my first engine swap I got confused and didnt have time to put some things in properly as far as the electrical goes... my reverse light switch is one of them. Is there a way I can just make an in dash switch?

My front diff mount is broken... I put a pinion snubber in before it broke but after later inspection it wasnt preloaded. Do I have to drop the subframe to swap it out?

Lastly my left side rear wheel sticks out more than the left. I dont know why i dont know what to do. the car seems to handle fine. It never felt stretchy in aggressive driving.

Lots of stuff there. I appreciate any insight.

 

alt should read at the very least 13.4 volts at idle and at all other speeds between 13.4 and 14.4v.

With the car off, check the resistance between B+ on the alt and B+ on the battery. Then check the resistance between the engine and the ground terminal. These should be less than 0.25 ohms.

 

I think Im measuring this correctly. My meter is set to 20k Im getting .06

My voltage seems to be more aligned with what you said. I tested again and my ecu reading is telling me about 13.7 with my lights off. My fuel pump (Aeromotive) seems to pull a lot of power. At idle I usually get around 12.5 volts.

I think I need a new battery, though this one is only about 2yrs old. I left the lights on for 10mins and I could not start the car. If the car sits for more than a few days the battery dies.

 

Went through the wiring and the alternator is putting out more voltage. I'm not sure what exactly fixed it but I did something. But the car still does the click thing.

Can any body help with the reverse light? Or the other stuff?

 

Alternator fixed. Reverse light fixed.

The driver side rear wheel sticking out further than the passenger side. I don't know what's that about. It sticks out about a half inch. Any ideas.

 

due to the age of the car and necessary alignments i wouldn't be concerned with a 1/2" difference. if it's in the front even slack in the bolts can cause the wheel to shift slightly, when bolting the struts in i push them towards the inside of the car before tightening the bolts to try and minimize it. if the rear toe was adjusted it will cause the wheels to shift in/out slightly, a bent rear toe rod would be the most likely culprit.

 

It is in the rear. I had slide into a curb and bent a rod... the long one at the bottom. I replaced it and its still sticking out. Due to my slightly aggressive fitment the tire rubs on the left side when shocks bottom out. The right side is fine but it really looks funny and irks me.

About the diff mount. Can I drop the whole rear subframe 4 bolts and the shocks to replace it. Is there an easier method?

 

did you have the car re-aligned? that may bring it back in.



the way i do a diff mount is to remove the driver side rear wheel and put the car on stands in front of the crossmember.

loosen up the passenger side front crossmember mount nut and remove the driver side front.

disconnect the driver side shock.

pry on top of the front of the driver side trailing arm to a solid point on the chassis of the car to open up a gap between the crossmember and the chassis.

stuff a wood block in between to hold it in place. take the diff mount nuts loose with a long heavy duty extension and 17mm wobbly socket(a 1/2" impact and impact tools make this a 30 second step) and pop the mount off the crossmember and jack up the nose of the diff.

loosen the 19mm diff mount to differential bolts and weasel the mount out of the car however you can.

reinstall in the reverse order.

with experience it only takes about 45 minutes with this procedure, most time spent getting the diff mount back into the cradle and front chassis mount to align with the pin, this all just requires prying angles.


use care and keep body parts away from sitting under heavy objects.

 

Yes this happened 7 months ago. Car was re aligned.

 

updated diff mount procedure^