Now available as a cost savings kit! Eight new Bosch CIS fuel injectors with eight holder bushing O-ring seals. If your 1977 to 1985 8 cylinder has over 120,000 miles and you think your injectors are ok then you might want to think again. I have been amazed with the poor results of our recent testing of large number of fuel injectors from various gas engine models ( 1977 to 1993). Less than half of those injectors tested passed a simple spray pattern and leak test. Unlike diesel injectors there is no way to take them apart, adjust, or rebuilt them. It is possible to send them out for ultrasonic cleaning but in cases where cleaning does not help your only option is to replace them. If you can't get them properly tested you may not be sure of the results and in the end just wasted time and money for cleaning. Install new from the start and know you will have improved fuel economy and smoother performance.
We highly recommend you also replace the injector rubber seals. Failure of these parts can lead to high idle speed and rough running. Plan to always replace them when removing and reinstalling fuel injectors.
- for seals for engines up to 1980 and for seals for engine 1981 to 1985 look below.
If your engine idles rough, quits after startup, smokes, and/or delivers poor fuel economy, it may be time to replace the injectors. Spray timing and pattern are critical to top engine performance. They must be spraying with a full and fine mist. Take a look at the images below of injectors I recently tested from a 300E.
Now take a look at testing a brand new injector. Notice the difference!