Hi, my classic has developed a slight lumpyness/ hesitancy at low engine speed, not sure what it is. Maybe just some dirt in the fuel system it did get quite low on fuel before it happened, but is there anything else i should check? thanks

 

Is it just at low speed? Could be MAF sensor, try unplugging MAF whilst car is started and see what happens.

 

Check your throttle body for excessive oily contamination.

 

Unplugging Maf will tell you nothing.
Do a diognostic check using self cel method.
Could be O2 sensor,coil packs,spark plugs ect ect ect

 

Got the same problem with mine, not been able to find the cause in 9 months. Changed ECU to the prodrive SP, plugs changed, then regapped but didnt help, MAF isnt that old, previous owner changed it a couple of years ago, HT leads were new last year, i've also swapped the 02 sensor, recirc valve, boost solenoid but it still does it. Next is to change the injectors over, got to get there eventually, even though it's not very apparent, I know it's not right and it really bugs me and I want to find the cause. I've had no CEL lights to help either.