Check the O-rings on the injectors and injectors seat.

 

i did that a few times, they are good.

 

I would change the plugs. NGK BKR7Es or Autolites 3922. Like someone said earlier, the 60s tend to idle poorly compared to the 42s or stock. I will be sitting at a light and the car will just start shaking, but I don't throw any codes.

 

I changed the plugs twice. Does the same and still throws a code for misfire in cyl 3. Could running lean do this??

 

But didn't you say that you tried the stock injectors and tune and still experienced the problem. Did you do a case relearn when you switched pcms?

 

a case relearn????

 

it's not the plugs. check the connections on the coil packs.

check the injector seals

i am betting you have an vacuum leak

 

I checked the injectors, like 3 times!! could I have a bad coil pack with a p0303??

Wha this case relearn??

 

move the coil pack to a different cylinder

there is dirt around the outer rings, and below the injector cup. these must be spot less when you put them back in. the injectors must be firmly planted in these buckets.

if they are not. you will have a leak.

 

if you have a leak there, when you step on the gas it boggs down, been there and had to fix lol. I don't have that problem at all! I am getting way better fuel economy than when I had gm stage 2 which makes with think that i could be too lean. Or maybe it's a coil pack

 

Well you are going to get better mpg either way because the GM stage tune is RICH so you're gonna be leaner. Like Area said and I said check the orings again man. I was having a misfire problem and I threw the 03 code once as well and sure enough it was an oring

 

I'll check the o-ring. Which cylinder from left to right is 3??

 

A crank case relearn is done by a new pcm (this isnt needed if you send in your pcm and have it tuned, this is only if you buy a new pcm)..

The crankshaft relearn teaches the ECU the variation in crank signals. The ECU uses this information to help command the proper amount of timing. If the relearn is not performed then the ECU may use an incorrect variation and the resulting timing may be different than commanded. This can vary from less timing and reduced power to too much timing and excessive detonation.

Anytime the ECU, camshaft, or crank sensor is replaced this relearn should be done.

 

the case relearn will not cause a misfire.

the closest to the timing chain is number 1 {passenger side when looking at the engine bay. }

 

I had no idea if it would cause a misfire or not...

Did you switch around the coilpacks?

 

it won't. end of story

 

so cyl 3 is the 2nd to near the driver side??

 

yep. pop the hood and its 1 2 3 4

 

Ummm...check the connections on the plugs and make sure they're tight? i threw a misfire code before and it's because i didn't FULLY connect the plug wire. It was only half connected...

 

thanks for the insight. I will check that and now I'm getting the first misfire which is a random misfire p0300. it's not the coil packs cuz I swapped them and it didn't do anything. The 60's are hooked up with the wires and connectors on the bottom not top right??

 

Try un plugging and re plugging in all your spark plug wires from the plug and the coil pack. make sure all your connections are tight. And if i'm not mistaken, a random misfire happens when the car is outta time. You might wanna check with ZZP and make double sure you have the right pcm and that its tuned for 60's and your pulley, cuz if it's tuned for say 42's and a 3.1, you'll have a timing issue. <--I could be wrong on that, but if i am i'm sure someone on here will make sure i know it lol

 

I contacted zoomer to ask, on the back of the pcm it said 60's but they did not tune for the size pulley that I have on. I already checked the spark plugs, ut just want to make sure that the injectors go with having all the hookups facing the bottom of the car vs the top.

 

I don't think the wiring of the injector would be a problem. If you had the wires on wrong, it just wouldn't work most likely. I could be wrong tho, I'm not sure about that part. I can tell you that ur most likely throwing that code because they didn't tune for the pulley you have on there. More boost vs less boost means you have to have timing/knock retard and yada yada so you don't get detonation. I would contact zoomer and see if they'll fix it for you or what. And if not, find someone with hptuners that'll help you out or somethin.

 

I'm definetly not sure bout that one! I'll check into that

 

I have a 2007 ss supercharged with a 2.7" pulley 60lbs injectors a retune and I started to see a p0300 and lately its just been a p0303. I got new 60lbs injectors and that didn't fix it, but there seem to be many more ideas on this thread. I also cleaned the throttle body (something I do regurlary now as it does my the car rev like crazy) Ill keep everyone posted on my findings.