Is there a way to check if the injectors are firing when cranking the engine?
Trying to start an FD that sat for years. New plugs, tank, gas, filter, battery. Did a compression check and its decent. about 110 on a piston gauge. Car cranks with a couple of pops and sounds of occasional almost starts but goes back to cranking. I checked for spark and have it. I had Stephen (mobile mechanic) who is on this forum, great guy by the way and he looked into the housing to check the seals and one showed that it could be stuck. I did put ATF and MMO in the plug holes and let it sit over night. Also when I pull the plugs after trying to start to the engine they clean as new. No residue of oil or fuel.

 

You can get noid lights - they plug into the fuel injector connectors and will blink every time the ECU tells them to fire.

Also you can typically smell gas on the plugs or out the tail pipe if the injectors are firing.

Could be possible the injectors are clogged or stuck too.

Dale

 

I also forgot to mentioned that I had all four injectors cleaned and balanced.

 

Dale, do you know which noid to get? From my research I see that there are two for bosch. I have the stock 850 and bosch 1600 (old).
Thanks

 

Not sure exactly, I've never had to use them. Harbor Freight has a kit with multiple lights for different connectors, that may be a good way to go.

Dale

 

You can get a set of noid lights in a little box. They each light has different pins for different injector plugs. Most autopart stores should have them or you can buy a set from Amazon.

 

Thanks. I plan to do that.

 

use a 12v battery and put power directly to the injector. either it will click or it wont. polarity doesnt matter

 

I agree with the 12V battery test, be careful not to short-circuit anything while you're in there. It seems pretty common for injectors to act stuck or clogged if they sit dry for a long time after being cleaned. Sometimes you can un-stick them by just connecting to battery voltage, and sometimes they might un-stick if you tap them gently with a small hammer while they are connected to battery voltage.

 

So I ended up purchasing a set of Noids and I was able to confirm that only one of the two connectors for the primary injectors is getting a signal.
Can anyone advise on how or where to further check why this is happening? I know it's an old ecu so many of you might be to young to know about the E6k.... Lol
Thanks!

 

One wire should be 12v with key on, the other wire is tapped to ground every time the ECU wants to fire the injector. Most likely the connector or the wiring is bad. See if the 12v is good, and if so, then test the continuity of the wire from the injector to the ECU.

Also make sure you don't have the secondary and primary injector plugs swapped around.

Dale