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My car has suddenly developed a miss or more of a surge just on low load between 2000-3000rpm,it is intermittent,the air fuel ratio goes to rich when it does happens,it is either one injectors playing up or coils,changed the coils over and still there,if I rev it pass the 4000- redline then there is no problem.
any thoughts of what it could be would be appreciated.

it's probably your leads?

I will give that a try tomorrow.Thanks

Changed the leads,changed the spark plugs but still there,it only happens when it warms up,it got a Haltech computer running the car.

Screwed o2 sensor?

Are you running a standalone (eg E Eight) or piggyback (eg interceptor)?

If its an NB or ownards and your running a piggyback are you throwing a CEL? (check engine light) If you have a CEL, have it read via an OBDII scanner and if it correlates to P0301-P0304, it is most likely an injector. 01 refers to misfire in cylinder 1, 02 refers to cylinder 2 and so onwards. You will be able to pinpoint which injector is failing.

Misses/surging is noted on fouled/leaking injectors, easily fixed by having them cleaned, seals replaced and flow tested. Are the injectors new? Have they been flow tested recently?

If its not an injector issue then the haltech MAP that your running may require some interpolation, where the load cel moves around between several sites (fuel map) and if the values are a little too different from each other and the end result is a jerkyness/flatspots whilst driving, easily fixed by some smoothing or tweaking of those sites.

If you feel its an MAP issue, perhaps email scott@haltech.com with your MAP, Im sure he will be more then happy to assist you.

I'm running a Haltech E6X,iI'm feeling it could be a injector that is doing it,I will get the other set cleaned and replaced them ,I told my tuner who is a Haltech dealer as well about I feel that it runs on 2 maps when it feels like it,but all he says it shouldn't do,how do reply to that after you have told him 5 times,but I can see on my wideband sensor that it does,that is an answer you get when they don't know and usually blames it on other hardware.
It could well be the sites you are talking about that is out of sync,will send my map to Haltech and see.

Might also be helpful if you do some data logging and send that along with your MAP.

The feeling is more like when you are running low on fuel,but if i rev it pass 3000rpm then no problems,it mainly happens when it has warmed up.
Replaced the leads,injectors,coils,fuel reg and it still doing it,as I said before only randomly happens for about 5 -10seconds,the pump was replaced 5k's ago and new fuel filter as well,any more ideas would be appreciated.