84 325e no start

[Jrgicehc]

So I have this 84 basket case that I picked up not running (Clean shell though!). Cant seem to get it running, here is what I have found so far.

Good compression
No grounds to engine- put in new grounds
Bad main relay- replaced
Crank sensors had broken connectors- replaced with new ones
Spark appeared but i still had no fuel.....
Both fuel pumps would not run when jumped- replaced both

Now I am in a position where it has fuel pressure when cranking, I also have spark but no fuel in the cylinder (plugs are dry). I have access to a snap-on scanner/scope and did a signature test on injector 1 from the signal to ground and the scope was flat lined. so I have no injection signal. does anyone know what would cause this?

[jalopi]

You should try scoping the crank position and reference sensors - I think they get their signal from a tab on the flywheel. I've heard these tabs can break/fall off.

[603Racing]

+1 - and make sure the connectors aren't swapped for the two crank(flywheel) sensors.

This signal is used by the ECU to tell the injectors when to fire. If the signal from the sensors looks good and the tab is on the flywheel, then it might be the OBC relay box. The relay box can go bad and cause a no-start (but I think it cuts fuel and spark). Anyway, to eliminate OBC relay you can jumper the two green wires together that go to the box.

[Jrgicehc]

thanks for the reply on this guys, I swapped my ECU out with one from a running vehicle and now I have an injection signal from the ECU. I actually am not sure if I did my first test right so I might have had it all along. Regardless i still have no fuel getting into the cylinder. I guess the only thing left is plugged injectors? is that a common problem?

also, I have fuel coming out of the regulator, so there is fuel getting to the injectors.

[jalopi]

Shit, yeah... should've mentioned that, especially since it wasn't running when you bought it, sorry bro.

Used to run into that all the time at my old job. We would get junkyard engines in for customers and sometimes have to swap the injectors from the original engine into the new one. Gas'll varnish up pretty good and keep the injector valves from opening.

Try finding someone with stock injectors and see if they'll let you borrow them. Either that or buy a new set, they're not that expensive. Also, there's a dude on the forums that has an ultrasonic machine. He cleans them for about $40 plus shipping to & from your house.

[Jrgicehc]

troubleshooting over a forum is always tough, thanks for the input again.

I have another running e30, so I will just snag the rail off that. I am caging the car and I just want to get it running before I start ripping the dash out of it so I will have plenty of time to get the injectors cleaned.

[Jrgicehc]

Just got the car running an hour or so ago. So to recap for searching purposes.... along with the problems listed in the original post, the original fuel injectors were stuck. The car actually ran with both ECM's so I must have screwed up my first signature test somehow (probably should have just rented some noid lights at advance). As my driveability teacher in college would say "if you come to the conclusion that your ECM is bad, do everything over again, if you still come to that conclusion, do it over again"

thanks again for the help 603 Racing and jalopi

[jalopi]

no problem.

by the way, noids are like $20 from harbor freight if you've got one around your area

[603Racing]

you're welcome, glad to be of assistance