mmm2742

i recently had a blow out on my 90 Ford PU and changed the left front tire. I tried to start the engine, but it wouldn't start, i towed it home. it had gas, I checked that. I had a friend come over and we started troubleshooting. There was fire. I looked in the owner's manual, reset the inertia switch, but the fuel pump would not kick in. I replaced the fuel pump, but it still is not kicking in. i had the inertia switch tested by a mechanic and he said it was good. it does make a rattling sound, is this normal? I'm thinking or replacing it anyway as well as the fuel pump relay. any suggestions. The truck never had issues until the blow out. Definitely i'm not getting power to the fuel pump. i appreciate any advice before i tow it to a shop.

techrep

iTrader: (1)

If you installed a new pump already...try a fuel pump relay next...are you positive the switch is re-set ??

Pmoon

I'm sure that you've checked the fuse, right?

mmm2742

yes, i reset it, will go buy a new fuel pump relay today. thanks!

mmm2742

Yes, i did, thanks for the reply.

Nitehawkjr

Do a voltage check on the system to see where you have lost voltage at. That way you wont start throwing parts at it without needing them.
Also you can check the relay to see if it's bad they're not high but no need buying one if it's good.

5Rangers

I recently replied to another post for a 90 fuel pump problem. In the post I detailed troubleshooting the system with an explanation of electrical flow. I included a Ford system schematic for the fuel pump electrical.
The point is that search is your friend.

Edit: I'll do you one better and save you the hassle of the search.

https://www.f150forum.com/f10/help-f...roblem-133372/

mmm2742

Thanks for the information! i do have the Haynes Repair Manual for my pick up so i will thumb through it again.

mmm2742

Yep, i purchased the relay switch, still no juice to the fuel pump. will check the fuses again.

5Rangers

If you look at the schematic for the 1990, you'll see the pump circuit doesn't get its power from a fuse. It gets it from fusible link W.

While the Haynes manual is informative, the schematic I provided is specifically for a 1990 F series and is a Ford publication. Use what you want and good luck.