Car wont start after fuel pump replacement.

[e30fix]

last week i swapped out the gas tank and found out that my intank fuel pump wasn't working. the motor was cranking but because of the intank fuel pump, it wouldnt start. So i ordered a new one and installed it today, everything went smoothly. I turned the key to the on position and the fuel pump is working. i go to turn the car on and it cranks once. It sounded as if it was going to start but it died? i try again and now i dont hear anything? the pump isnt making noise anymore. I tried smacking the starter to see if anything happens. Nothing
i checked the fuse relay and tried another one. Nothing.
I checked the sensors near the bellhousing and they look ok? anyway to test them?

i have a 1984 325e with a stock m20 motor. 5 speed. i am lost and need some guidance. thanks in advanced.

[hwy84]

Killed the battery cranking away with the bad pump, and don't have enough juice to start the car now?

Easy fix if so. Heh.

What else did you disconnect when you removed/replaced the tank?

[e30fix]

I took the battery to get charged so the battery is good. I reconnected everything, driveshaft exhaust etc.

[reelizmpro]

Did u put in the same size gas tank? Did u check the main pump to see if it's working as well?

[e30fix]

Nope I put a new tank, 4 gallons of gas, and checked the main pump. The main pump sounds fine. I just don't get why the motor won't crank at all now?

[hwy84]

What's the battery voltage? No crank at all, knowing that the battery was drained and needed charging, feels like the battery is unable to hold charge, or not fully charged. Rule it out with a voltmeter, if you haven't already.

Does your grey market car have power windows and mirrors? Do those work with the ignition on? If not look at your unloader relays. If so...

I guess it's possible that the starter gave up, or the fusable link blew. (Did you connect the battery backwards for a second when you put it back in?)

No crank doesn't seem like a fuel pump issue nor a sensor issue (those would be crank but no start). This seems simpler.

[e30fix]

Wow thanks for the help. All the electronics in the car were working fine so I ruled out the battery. I don't have power windows or anything so I figured it was something else, but I decided to take the battery from my wife's car just to rule it out completly. The car turn on right away. It's running rough but I'll do some maintenance soon and get her on the road. Thanks everyone for all the help!

[hwy84]

Right on! Glad it was an easy fix!