No knock sensors on the E30.
Cam sensor is a problem, but not critical. Fix it later.
No fuel usually means a bad crank sensor or a bad pump relay. There are three relays on the firewall, separate from the relay box on the wheel well. From left (passenger side) to right (driver's side) they're the O2 heater relay, fuel pump relay and main relay.
First off - to test the crank sensor, pull the plug out and put a multi-meter on it. You want to test the sensor, not the chassis wiring. Don't test the harness side (goes to the DME). Test the sensor side. The sensor must have 640 ohms between pins 1&2. Pins 1&3 and 2&3 should have very high resistance...100Kohms or so. PM me if you don't understand what I'm saying. This is important! If the DME doesn't get an excellent signal from the crank sensor, it never turns on the fuel pump. I'd also unbolt the sensor and carefully clean it up. It should be very close to the trigger wheel, like credit card thickness. If it's too far away clean up the mount socket and check the mounting plate.
Next, test the fuel pump and relay:
Cut a short 4-6" bit of good 14 gauge wire...strip a bit off the ends to make a jumper wire. If you want to get really fancy, crimp a pair of male spade plugs on the ends. Use that jumper wire to short FP relay socket pins 30 & 87. Turn the ignition switch to position II, the pump should run continuously. If the pump doesn't turn on find out why. Pull the rear seat & inspection cover and directly jump the pump connectors with 12vdc off a charger or car battery. Check the harness as well - I've seen wires pull out from the connector plug.
If the pump works, test or swap the relay. It's a standard four-pin relay...easy to replace. In a pinch, the windshield wiper relay is the same, swap them out. You can test the relay by putting 12v on pins 30&87. You should feel the relay snap shut...and you should see zero ohms resistance (continuity) on pins 85&86.
Topic: New to this engine, have a few questions to ask (Read 2776 times)