Intermittant running problem 2

[BLUETHUNDER]

After curing my car of its running problem with the fitment of a new fuel potentiometer every thing has been running fine for the last five months,until last night.On the way in to work the car was running fine then all of a sudden the old problem returned with the car feeling like it was only running on five or six cylinders,got the car to work,checked the markings on the fuel pots and both were in line,but one of the screws holding the fuel pots on was loose.Tightened it up but still had rough running and a bad smell of neat fuel coming from the left bank.On the return trip home the car continued to run rough then after about three miles the car came back to life and returned to its normal self,i then went on an extended drive for about twelve miles and it never missed a beat,but i have a nagging feeling this problem is going to return.Any one else had this problem? and should i be looking elsewhere than fuel potentiometers? Any help most appreciated.

Mark

[longbow]

Well, I'm no expert BUT I have played around with those throttle pots and I know if a screw is even slightly loose it will induce big errors, hence the rough running. When you tightened it up, the engine will have adapted itself back using the O2 sensors to trim the fuel map accordingly, and hey presto the engine will have recovered. I'd reset the pots using the software to make sure the adaptive are reset back to as close to zero as you can get them.

[BLUETHUNDER]

I havent got the software available to me,i did notice with the loose screw that you could move the pot with any effort,i moved the the pot back to what i thought was the correct spot and with the help of my hearing and the rev counter tightened the screw to what i thought was the right position.Ive got to say that the return to normal running from rough running was instantanious it wasnt gradual,if thats any thing to go by.

[simonsparrow]

I concur with Windsor, I've spent a couple of weekends setting up my car, and its still not quite right. The throttle pots seem very sensitive, I've been setting them with the screws just nipped up so that I can move them round, but a final tightening of the screws seems to change the settings.

I also noticed that the adaptives seem to increase by about 5% when the fans kick in (I've got mine wired to come on together), so I gave up trying to set it up until the fans switched off.

I also tried setting the car up using the graph on the laptop only, but in the end reverted to the airflow meter to set the balance.

Sure is tricky! (or could be my engine etc.)

Does anyone else find the setup difficult?