Don't waste your time with the fuel injector cleaner, it's worthless. I can't remember where I read it but there was a whole writeup on why it's no good.
Sounds like you might want to give it a good full tune up...fixes lots of little quirks...I believe lots of folks here will agree to that.
This my usual tune up routine...plus the 'Tech Section' here can be very helpful too.
Dugan Racing sells a 'tune up kit' comes w/ Motorsport 9mm wires, Autolites, fuel filter, oil filter, cap and rotor. I'm sure there are other places that offer kits like this.
I've used them[tune up kit] for a couple of years and have never had any complaints.
Also, I've started something new in my routine for tune up. That is getting a can of 'Cee foam' from Carquest. Running it through my intake via a vaccum line, while the vehicle is running. Great trick with obvious results.
Clean you K&N filter...assuming you have one, if not, get one.
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'95 Gt (sapphire blue)
full saleen body upgrade
typical bolt-ons
wish I had a money tree.
there is a post around here somewhere that tells u what it is. i had the same problem with my car. that scratching noise , kinda sounds like marbles is ur engine pinging. the solution is ur mass air sensor. clean that thing with alcohol. u'll need a screw driver with tamper proof bits. hope this helps
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94 white gt
off-road h, 2 chamber flows, 3.73s , king cobra clutch, :)
In response to the rattle under the car..mine does the same thing...i got a h-pipe which runs right along the sides of the transmission, so when i stepped on it, it would rattle against that. If thats the problem just loosen the bolts, pull it to where u want it, and while holding it in position tighten them back up. That worked for me....
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306,Probe Forged Pistons,Eagle Rods,Edelbrock Victor Jr. Heads,Trick Flow 1.6 RR,Hardened pushrods,Comp Xtreme Energy Cam, Trick Flow R Intake,BBK 75mm Throttle Body,Trick Flow 75mm Intake Elbow,BBK Fuel Pressure Regulator,FMS 9mm Wires,BBK CAI, BBK Underdrive Pulleys,3/8 Plenum Spacer,3:73's,BBK equal length headers,BBK h-pipe,Dynomax UltraFlow Mufflers,Cobra R Hood w/ SVO Scoop,95' Chrome Cobra R's,Pro 5.0 Shifter,Pro-M Mass Air,24 lbs injectors,MSD 6AL, Blaster coil VORTECH NEXT WEEK :)