Was my ECU grounds regrounded them now car runs great

 

I seem to be having this problem still. been doing my homework on here and adjusting it to the car (S4 TII) still no luck.

1.) Grounds seemed like a major issue w/ this prob so I cleaned off most of the grounds and sandblasted the bolts back to shiny.

(Chassis Shock tower , upper bolt on Tranny / engine (under oil filter) , bolt on engine under UIM , ECU Grounds re-grounded 3G, 3A, 2R, 2C, & few misc others that i could find)

2.) Ran a vacuum test to check the exhaust under reving (w/o load) Checked out marginal. So i drilled a small hole into my exhaust pipe to see if it would help out. Still didn't run any better. Now its somewhat loud @ idle , still sounds okay cruising.

3.) TPS is brand new from Mazda , fixed a few idle issues after calibrating. 1st Plus so far , but not what i wanted to fix.

4.) Boost sensor re-grounding tried that. Blew EGI fuse, read on a few posts "86 Only, do not re-wire new models" 3bucks and 40mins of my time lost there.

Reading more posts online , but most of them covered what I have already tried.
Any more ideas from others , much appreciated. Prob end up saving up to get exhaust (downpipe / Cat) since its still stock and theres a hole in it now. See how that goes afterwards.

Again, any ideas / knowledge to spare on this issue much appreciated. /scratching my head too much now

LD

 

Not that it will matter immediately but those bolts you sandblasted are going to rust heavily and fast. Bolts come with a protective finish (typically zinc) and you've removed it.

Rather than blast the bolts it's far better to replace them with stainless and cover the connection with grease for a long lasting fix.