Rough idle and fouled plugs
Rough idle and fouled plugs
I bought my 81 with FI in July of this year. When purchased it was running well and had good power but had a rough idle and it was set at 1500 RPM. After solving the trapped air overheating problem I have been slowly working on the idle issue one step at at time. I have looked for and repaired several vacuum leaks and attempted to adjust the idle down to 800 RPM. When I pulled the spark plugs #1 and 2 cylinders plugs had a large amount of brown deposits on them. 3 and 4 looked ok but in need of replacement. Replaced the plugs and it improved smoothness and power but did not eliminate the rough idle. Next replaced the dist cap and rotor. This too improved the way the car was running but did not completely eliminate the rough idle. Next adjusted the timing per the manual at 10 degrees BTDC and then readjusted the idle speed to 900 RPM. Again this improved overall power but did not smooth out the idle. Pulled the plugs and #1 and 2 have black deposits on them, 3 and 4 look almost unused still. Only suggestion from my mechanic at this point is to readjust the valves which I plan on doing while the car is in the garage for the winter. The car still has plenty of power and runs down the road smoothly but I'm a little bit anal about fixing the idle and want to know why there is a difference between the cylinders. I plan on checking compression soon as well but haven't got to it yet.
- azruss
- Posts: 3659
- Joined: Sun May 30, 2010 12:24 pm
- Your car is a: 80 Fiat 2000 FI
Re: Rough idle and fouled plugs
have you had your injectors cleaned and serviced. sounds like #1 and #2 injectors are dirty
- 124JOE
- Posts: 3141
- Joined: Fri Jun 24, 2011 7:11 pm
- Your car is a: 1978 124 fiat spider sport 1800
- Location: SO. WI
Re: Rough idle and fouled plugs
when you do everything correct people arent sure youve done anything at all (futurama)
ul1joe@yahoo.com 124joe@gmail.com
ul1joe@yahoo.com 124joe@gmail.com