3000GT AWD V6-2972cc 3.0L DOHC Turbo (1991)
Valve Clearance: By Symptom
Engine - Rough Idle Prior to Delivery
NO.
TSB-91-16-003
DATE
July, 1991
MODEL 1991 3000GT, 1991 Mirage 1.5L
SUBJECT: ROUGH IDLE
PURPOSE
This Technical Service Bulletin describes how to correct rough idle by cleaning the spark plugs. On the 1991 Mirage with 1.5 liter engine, valve
adjustment is also a part of the procedure.
AFFECTED VEHICLES
1991 3000GT and 1991 Mirage with 1.5 liter engine.
DESCRIPTION
Due to the short, frequent engine use associated with the transportation of new vehicles, some 1991 3000GT and Mirages (with 1.5 liter engines) may
develop a rough idle prior to delivery to the customer. If a rough idle condition is present, it will be necessary to remove and clean the spark plugs and,
on Mirages (1.5L), adjust the valve clearance.
To correct the rough idle condition, perform the steps shown below:
NOTE:
Always wear safety goggles while operating any type of machinery.
1. Remove all spark plugs from the engine.
2. Inspect the end of each spark plug. If any are wet from engine flooding, clean them with carburetor cleaner or other suitable de-greaser. Using
compressed air, dry each end thoroughly.
3. Insert each spark plug into a spark plug cleaning machine, rotating the plug to achieve full cleaning action. Refer to the following limitations on
cleaning time:
Note:
The cleaning time durations shown on page 2 of this TSB are applicable to NGK and Nippondenso plug cleaning machines. If using a
different type of plug cleaner, follow the recommended plug cleaning times for that machine.
Plug Cleaning Machine
NGK and NIPPONDENSO SPARK PLUG CLEANING MACHINES
a. Spark plugs for the Mirage must not be cleaned for more than 15 seconds.
b. Due to the use of platinum-tipped electrodes, spark plugs for the 3000GT must not be cleaned for more than 11 seconds.
OTHER MANUFACTURERS' SPARK PLUG CLEANING MACHINES
