Rough Idle On Cold Start Up

[Bonjaz]

On cold start up starting approximately a few weeks ago my xr idols really rough for about 3seconds then jumps up to normal idol. If I go for a bit of a drive and come back a few hours later the car starts fine its only if the car has been sitting overnight or all day. also approximately 2 weeks ago I installed 2 10" subs and a 1550w clarion monoblock, the amp is turned right down and I dont listen to loud loud music ever so I wouldnt imagine it would draw heaps of current, but I am wondering if its possible that my fuel pump isnt priming properly now I have added another load on start up, the battery is relatively new. I will test the theory tomorro, make sure I can hear the walbro priming then maybe do it again then start to see if I get the problem. Or I might disconnect the amp from battery and check if it primes properly. Just wanted to get a few opinions if my theory checks out???

cheers addie

[millers]

mine idles a little rough for a second or 2 or I just turn it straight on. if I turn the key to start and give it time to prime the pump then it starts perfectly. I have recently changed the fuel pump because of another issue and it hasnt changed this bit.