OK This is the 2nd time i have posted this. i need help with my fc. it has high rpm break up bad. at about 4-6 it spits and sputters then at 6500-7k it acts normal. and at night it does this with the headlight on at around 3400-6k. i turn them off and it acts the same as above. what the hell it going on here? is it the coils, Alt some ground not connected?

 

Have you checked your spark plugs? Measured the alternator output?

 

spark plugs+wires are new would that be the issue? ill check that today and let you know

 

Check your Grounds.

 

Used Arroncakes guide for grounds all of them are good solid grounds and all hooked up. i wasnt able to check the Alt output my meter was not in my tool boox where i left it i will check that tmr.

 

ok i checked all grounds checked the Alternator output its right around 13.8 with the headlights on and 13.4 w/o. could this be bad timing or a bad coil? could the headlights be taking all the output from the coils and causing this? let me know

 

OK i Checked the Ohm resistance in Both the coils and they are to high they should be .5-1.0 ohms. Is that bad? would That be causing the issue?

 

Did you check the grounding at the boost sensor?

 

boost sensor? mines a N/A

 

the ecu ground. do i have to remove the upper intake to get to it or can things be moved around slightly? if i need to move them around am i going to need a gasket set?

 

Look in the FSM, it tells you where to check.

 

ok this is crap! i fixed all the ground including the ecu ground with new wires and connectors. It went away for 1 day now its back! should i replace that batt cables? they are the ones you get at autozone as a temp cable connector.

 

So did you check the ground at the boost sensor?

You can get proper battery cables at AutoZone, or at least, you can at every auto store I've ever been in. They come in various sizes with lugs cast onto each end.

 

I believe he is talking about the pressure sensor, located on the passenger side shock tower, behind the airbox, and right beside your 2 green plugs.

 

oh that one. i replaced that ground with a new wire and connector from Mazda. as for the battery cables i am going to replace those tomorrow as i dont have any money right now till then.

 

Nope, I am referring to the boost sensor.

In the FSM, Mazda refers to the NA map sensor as a boost sensor, and the TII MAP sensor as a pressure sensor. Go figure. Using the proper lingo makes it easy to find in the FSM.

 

ok ive replaced all grounds had the alt tested battery is new. could this be a secondary injector problem?

 

ok i figured it out !! the person who had the engine pulled and rebuilt put the MAIN BATTERY GROUND DIRECTLY TO THE BLOCK AND NOT THE STARTER BODY BOLT! i moved the wire to the starter and it went the F***** away! gone works great! now just have to get the trans checked! hear clunking when i change gears! im thinking that is a trans mount or a rear end mount.

 

For the transmission, I would start by checking the oil and check the records to see if the correct oil was used; both misusages of the oil can cause noise.

If those checks deem no solution, it can be a warn bearing; throughout (you may have constant noise) or polite bearing (it will not go into gear), wear of the countershaft gear, surface gears wear or damaged teeth.

 

Putting the ground on the block should not be an issue. It was more likely just a poor/dirty location that was chosen.

 

I took it in to my cousins Trans shop on monday. And found the read end front mount broken which is the clunking and found i need to have the drive shaft rebuilt or replaced the u joints are worn.