Removing injectors on 91 740 turbo

twlaub · Post by **twlaub** » 29 Sep 2006, 20:48

I am trying to remove the injectors on a 91 740 turbo but they don't seem to want to come out. I have removed all the bolts (three) on the fuel rail that runs across the top of all four injectors. I have removed the retaining clip at the top of each injector. Everything moves and wiggles but the fuel rail will not come off the injectors and the injectors will not come out. I am unsure as to how much pressure to apply for fear of breaking an injector. Are these things supposed to just pull out? How hard should I have to pull? Any advice is greatly appreciated.

Post by **billofdurham** » 30 Sep 2006, 12:10

The rail, complete with injectors, should pull out quite easily but you should not release the injector retaining clips until you have the rail out.

The injectors do have O-rings on them and it is possible that they are stuck to the engine. The O-rings should be renewed when you replace the rail.

Bill.

twlaub · Post by **twlaub** » 30 Sep 2006, 18:42

Thanks for the reply. I'll get a seal kit if I have to pull them. However, I found that you can check if an injector is pulsing by listen through a screw driver. Place the end of a screw driver against the side of the injector and put your ear to the other end. You can hear the injector clicking inside. So I know the injector is pusling but still don't know if fuel is getting through (cylinder is not firing, has spark).

Post by **billofdurham** » 01 Oct 2006, 12:03

What problem did you have to make you want to remove the injectors?

Bill.

twlaub · Post by **twlaub** » 01 Oct 2006, 13:59

One cylinder not firing. I have verified that spark is there and compression is good. Fairly sure that no fuel to cylinder based on condition of spark plug on removal. I have traded spark plugs with a good cylinder. I have now traded injectors on the bad cylinder and a good one. The problem persists with the same cylinder not firing. So now I know the injector is good. Couldn't find a noid light locally so haven't been able to check that. Have verified 12 volts to all injectors. Now I want to unplug and replug the ECU to see if that does any good. Tried the screw driver listening to the injectors but don't believe that is a reliable method.