Hello all - I've scoured the forums and seen several posts regarding the same code (P20E8), and have tried every recommended action I saw in those posts. For background, this all started when I received the DEF heater code (P20BA), which was covered under Ford extended warranty. I had the heater replaced at a Ford dealer, and 2 days later had the P20E8 code. In the last few months, here is what I've tried:

- Replaced DEF pump, DEF injector, & DEF harness / hose (running from pump to DPF).

Still had code after my attempts, so took to a local shop, who replaced:
- DEF Pump; the pump I put in was reading <10psi, should be closer to 45 I believe, so they thought maybe the pump I installed was defective
- Code returned after a few days, they said the sender/heater was bad yet again (DEF level was not registering properly); at this point they said the DEF pump they installed was not functioning at all, so replaced the pump again under warranty

Less than a day after picking it up with yet another new pump, sender/heater, the code returned.

Am I missing any other obvious parts to replace at this point outside of the DEF tank itself? Nearing wits end here, and about at the point of exploring alternative solutions to DEF...

Thanks again

 

Well, I am definitely no Diesel mechanic, but after reading the description of the codes and you say you've replaced everything. I going to say you have a problem in the circuit. I have read that some people have been finding loose pins and connections in the GPCM. If you haven't checked that yet, it might be worth a shot....Good luck.