I tried posting this on another board so if anybody is having deja vu reading this now you know. Basically I installed a 9" and did the racetronix plug and play pump and harness while I was back there. Now when I fired it up the engine was missing and would not idle. Before the pump install the car would idle steady just below 1000 rpms. I thought it might have to do with the chassis ground they provide so I cleaned it and even rearranged the way they sit. Helped a bit but not much. It will now idle initially but if you give it gas it will start missing and when you let off it wont idle. Revs drop down to about 500 and starts to stall unless you give it gas. I checked the connections for the opti, all plug wires, injectors and now I'm starting to get lost. Any ideas?

 

Have you check the fuel pressure with a guage? Sounds like the added pump is causing less fuel instead of increasing it. Do you hear the new pump running? Mine is very loud compared to the intank one.

 

you can hear it prime and fuel going through the lines at the front (hood open). I kept turning the key on/off for about two mins, waiting for the security light to turn off, and now it runs good. Maybe there was air in the lines or something and the extra priming forced it out? Oh well...