Warren, check the basics firts, I think it would be a waste of time to get a tune for an intermittant running problem, at least pull the plugs for inspection. Yes, I agree the car needs a tune to perform at it's best, but I highly doubt it would cause this problem.
Open loop and closed loop simply are ways to calibrate fuel delivery, they WOULD NOT cause a misfire. If an 02 sensor goes bad, the car will still run fine, it has plenty of other sensors to help it keep the car running as it should. This sounds to me like a spark or fuel delivery issue, if the injectors are new, I'd look for a faulty wire, coil or plug. An inspection of all 8 plugs is a great starting point.
Are you sure it's a misfire? A misfire will usually set a code pretty quickly and usually flashes the MIL light to let you know it's a serious problem.

 

The code 1232 is a fuel pump voltage monitor code,meaning the fpdm is seeing incorrect fuel pump voltage..the fpdm maybe shutting down due to being overheated from your fuel pump drawing excessive current.

 

, i dont want to drop my tank again, but it will give me an excuse to run a bigger pump.


the wires were bought last year, FRPP 9mm, i just changed all the plugs the other day. they were black.

like i said it might also be the one coil pack.

maybe i will go down to ford an see what the want for one. or would a crappy tire one work fine?

 

A ctc coil will work,I would recomend installing a fuel pressure guage and test drive it till it acts up to observe your fuel pressure...also clear the dtc's and recheck for dtc 1232 after the car acts up.

 

Warren give me a shout if ya need a hand!

 

Ok, so i found out a little more.

I bought a new coil for the one that i thought could be screwed up.

So i installed it and started it, and then i went working on jens car. after 15-20 minutes, i heard the fan kick in, and the RPM's drop, then they went up, then down. each time it got lower and lower, until it stalled.

it did this also before the new coil pack.

 

Did you post this question on svtperformance? If your gonna get any help it will be on that site! Or maybe the Correl or even eectuning.org.

Good luck man!

 

But is it still misfiring? This sounds like a separate issue to me. Does it start back up? Will it stay running if you throttle it?

 

OK, the misfiring and bogging are gone now, I THINK. i let it warm up for 5 minutes and went for a drive, came back. worked fine. went for another drive, and still fine.

but it does still try/die when the fan kicks on....the up and down idle thing.
Also has high idle when coming to a stop unless you snap the throttle.

Maybe IAC, or tune now?

 

could be a vaccum leak also! try cleaning the iac, and check for leaks, or you may just need to drive it for a bit for it to learn a table, mine ran like crap for about 500 km after i put it back together!