HT4100 4.1, 4.5, 4.9 Discussion, Replaced Injectors.. Still no action in Cyls 3 and 4? in Cadillac Engine Technical Discussion; Originally Posted by N0DIH
I wanted to ohm out all the injectors, so I pulled the ECM and connected it ...
Automobile(s): 1995 FWB 100,*** miles CURRENT. 1991 Seville 175,000 SOLD
Re: Replaced Injectors.. Still no action in Cyls 3 and 4?
Originally Posted by N0DIH
I wanted to ohm out all the injectors, so I pulled the ECM and connected it up there. Make sure you safe the airbag for this!
You need to be a contortionist, but it was far easier than pulling the connectors on each injector.
It doesn't help much for operational checking, but it does help anyone who wants to check the injector impedance without pulling the connectors on each, which can be a real bear.
Would be nice to swap in a different ECM t rule it out (bad injector driver). Other than time, it would be an easy fix to repair it if you can find the right type of transistor for it.
You can check the resistance of injectors much easier if you disconnect a common connector for four injectors. One per fuel rail. One of disconnected connectors is shown in the picture. You need to measure resistance between
pairs of vertical pins. The other connector has 5 pairs of pins. You will figure out which ones are assosiated with injectors. Though it is tough to say right away which pair realtes to particular injector, you will get general condition of injectors. Normally the ballpark is about 17 ohms. Some of my injectors showed as low as 7.8 ohms . So I replaced all of them with Bosh 19 lbs. My idle is still rough. So that was not the problem, at least was not the only problem....