1990 240DL with 380k. Recently was getting codes 2-3-2 and 1-3-1. After reading on here decided to test the FPR uing a vac pump and blowing thru it. Seemed like it was bad not changing. Ok so replaced it and seemed to fix the problem for about a week. Now today it started ok then ran and soon as it warmed up suddenly poor acceleration, sputtered and dies at idle. Check light on same codes. So I started checking. Yanked the plug on the AMM while running and suddenly idle normal and able to drive again. Reset ECU. Plugged AMM back in sputters and dies. So got out the Haynes book and started checking. Haynes shows 2 tests. Ohm test of wire on term 2 and 3 I get 3.3 ohms. Plug back in start it up rev to 2500 rpm (guessing) turn off key and look for burnoff signal on white wire pin 4. Nothing. Can hear relay under passenger side click after 4 seconds. So I pulled the kick panel I see the ECU and the Fuel computer on the firewall and passenger kick panel. Up in there are a white relay, and other wires with 2 black plugs that have blue looped ends. I tried removing the white relay but this results in a no start condition. Put it back and starts up but same result. I guess my question then is where is the burn off signal and is it the culprit?
Haynes book is as stated in here fairly useless. Looking at the end of the AMM now that I took it out I can see the very fine wire in there looks good. Is that white relay the one used to trigger the burn off? There is no white wire going to it. Swear I used to hear another relay kick in after the 4 seconds and kick out after 1 second but not anymore.