I have a 86.5. I have noticed a slight surge in the engine. It seems more prevelant when the engine is cold. Mainly noticeable in 1st and 2nd gear. The car has been well maintained over the year. I have been fixing some do the little things. I would like to up grade the chip and install a X pipe in the near future. However, I know it needs to be running right first. There are warning lights on. Thanks in advance for any input

 

andyww,
A little more description/detail needed. What rpm surges to what rpm ? Warning lights are on - WHICH ONES ? Is this vehicle a manual or auto ?? Ya gotta help us.

 

check the coil wires make sure they are not rubbing on any part of their run,
also inspect the ends of the coil wires make sure the coil mounts both have ground wires to the engine.
Remove the intake tubes and run the car in the dark, see if any of the wires are arcing

 

My bad...I meant to say NO warning lights are on. I will check the coil wires and do the dark test tomorrow evening. The surge seems to be most noticable between 1500-3000 rpm. It is a manual trans car. When I say it does it when its cold, I mean it does it the most during the first 10-15 minutes of running...I do not mean "coolant temp" cold or ambient air cold. Once you drive the car for 15 minutes or so it seems to kind of straighten out. Other than this the car runs great. It starts right up, does not smell "rich" or any other issues. I bought the car a year or so ago. I have always wanted one. It has 86K miles

Thanks again
Andy

 

Test the Temp II sensor, as well as set the Base CO as per the manual.

 

Andy,
Here's a link to the 928 Workshop Manuals.
Get a good DVM (voltimeter) Sears/Craftsman. The manual it comes with will describe measuring resistance, continuity, etc.. if you are unfamiliar. If you are fixing to do some little things, getting familiar with this will be important on the 928.

http://www.2010.cannell.co.uk/manual...s_porsche.html

 

Thank you for the link. It will be a great help.