[DML] Re: Setting Fuelling - Why does the DMC PRV Hunt? [long]

["Shain Brannan" <shain@xxxx>]

Hello,

This is a subjest that i'm very intrested in. Eveyrtime that i go 
to a DeLorean event i see at least a half dozen cars start up, and 
do the idle hunt described. Being that i had/ have a low mileage 
car (7k when i got it, 10 k now) i never ever had a hunting 
problem. I currently run a porshe cis system on my car, but it 
mimics the the orgional almost to a tee with some exceptions. The 
one reason why i belive (belive being the key word, not experience 
just based off all the knowledge i learned during the switch) has to 
to largely with vacumm leaks, bad or dirty O2 sensors and 
adjustments. I have notcied that a large majority of cars that had 
water pumps replaced properly, did not have a a hunting problem. 
The oring seals that mate with the manifold shrink over time and 
could become a potential vacumm leak, also upon re assemble of the 
engine all the fuel meter or rings become replaced as well (if done 
correcty. My car when i first bought it was a low mileage garged 
vehicle, but i found small cracks in my vacumn lines all of which i 
replaced. I stress alot of vacumn problem, but there is a really 
good reason to. If you have a small leak, if/when you adjust your 
idle it would be off a good amount. Also vacumn is nessary to run 
the warm up regulator, and a certain amount of vacumn is nessary to 
open the delay side (i believe). All of this has influences on the 
idle and fuel fixtures. These are just some things i have notcied 
in the past, wether you belive them or not.

- Shain
#10140