Injection Pump (With Idle Speed Boost) - Changes
85VW2Applies To
GOLF, JETTA
1.6L Diesel Engine and Turbo Diesel
1986
Group 23
Subject
Diesel Injection System
Part Identifier N/A
Key Points
Injection pump with idle speed boost
A180
Number
85-01
November 8, 1985
The diesel pump now uses a manually operated idle boost, allowing better control of emissions and reduced vibration during idle.. When you pull the cold start cable to the first detent, the idle is raised to about 900 rpm. By pulling the cable out completely it increases to about 1050 rpm.
The modified pump includes the following changes:
1. Previous idle adjustment screw, sealed with tamper proof cap (cannot be turned).
2. Linkage with cap nut for idle speed adjustment.
3. Stop screw for minimum idle speed.
4. Stop screw for speed boost.
5. Tamper proof cap.
Idle speed, checking and adjusting
Requirements
^ cold start cable must not be pulled out
^ all electrical consumers turned off
^ minimum engine oil temperature 60~C (140~F)
- measure rpm using VW 1367 ignition tester and/or adaptor VW 1324
CAUTION
The idle adjusting procedure has been changed. The old idle adjusting screw is sealed with a tamper proof cap (see #5 in illustration) and can no longer be turned.
Idle speed, adjusting
- measure idle speed
^ specification 850 +/- 30 rpm If No
- turn linkage (2)
^ turning cap nut clockwise increases rpm
^ turning cap nut counterclockwise decreases rpm
Idle speed boost, checking
- pull cold start cable out to first detent idle speed should increase to 910 +/- 30 rpm
- pull cold start cable all the way out idle speed should increase to 1050 +/- 50 rpm
Note
The basic pump adjustment performed by the manufacturer, assures that normal idle and boost can be adjusted within the specifications. If, however, you cannot adjust the idle or idle boost within the specification; perform the following adjustment.
Idle adjustments
If the idle speed cannot be adjusted below 900 rpm by turning the cap nut because it hits limiting screw (3):
- loosen lock nut on low idle speed stop screw (3) and turn screw counterclockwise
- Adjust idle speed on the cap nut to 850 rpm by turning the linkage
- Turn stop screw in until it just touches low idle stop and tighten lock nut.
Idle speed boost
If idle speed varies from specification when cold start cable is pulled out completely:
^ specification 1050 +/- 50 rpm
- loosen lock nut on stop screw (4) and, with cold start cable pulled out completely, adjust idle speed to specification by turning stop screw.
- tighten lock nut on stop screw