You really need to understand the system, and how to diagnose issues.
These should help.

Fuel Injection

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https://www.google.com/search?q=bosch+jetronic+fuel+injection&oe=utf-8&aq=t&rls=org.mozilla:en-USfficial&client=firefox-a&um=1&ie=UTF-8&hl=en&tbm=isch&source=og&sa=N&tab=wi&ei=jLhpUJKeLKy20AHMqYGABQ&biw=1280&bih=883&sei=H7lpUNyUOK-O0QGYv4CQCg#um=1&hl=en&client=firefox-a&hs=gcj&rls=org.mozilla:en-US%3Aofficial&tbm=isch&sa=1&q=1987+420sel+bosch+jetronic+fuel+injection&oq=1987+420sel+bosch+jetronic+fuel+injection&gs_l=img.12...0.0.2.20912.0.0.0.0.0.0.0.0..0.0...0.0...1c.W3kwIfayHmE&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=b3de46ad5252a728&biw=1280&bih=883




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__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

https://www.boldegoist.com/