You certainly have a lot of trouble with this car! I remember when you first started posting, all the problems you had with the fuel system. Anyway, if you get out your Workshop Manual you will find in the Lambda section under the specs different things to do with the O2 sensor wire (appling a voltage, grounding it, and leaving it loose), and closing the WOT switch. You read the output with a dwell meter at the diagnostic plug and you should get readings close to what is in the manual. Keep in mind that you are reading an output directly from the ECU, not what is going to the FV. You might have to check the wiring from the ECU to the FV. A bad connection can cause the FV to not function. The ECU also has 2 ground connections that run through the bulkhead connectors by the ignition coil. You MUST have BOTH grounds at the ECU plug for the ECU to function. One of these grounds is the return path for the O2 sensor. If the ECU isn't properly grounded it cannot read the O2 sensor with only 1 wire! It is not normal for wires to be chopped up in there. This could be part of a missing ground circuit which would make the ECU look bad. I would open the plug up at the ECU and check out each wire all the way. In any case you have to troubleshoot EVERYTHING before you condemn the ECU unless you have a known good one to substitute. The Lambda ECU is not a high failure item. I would suspect a wiring problem or a dead O2 sensor first. Chances are that if the ECU can work by holding the WOT switch the ECU is OK (the WOT switch and wiring too!). David Teitelbaum vin 10757 --- In dmcnews@xxxxxxxxxxxxxxx, "stainlessilusion" <5n-@xxxx> wrote: > I just got my current ECU from DMCH just a few months ago, I'm > pretty sure it isn't defective?is there any way to test the > frequency valve part of it? How do I test the O2 sensor? When I > changed the plate that mounts all the connections and coil on the > engine bay bulkhead, I noticed wires cut and spliced into different > wires [behind the plate inside the pontoon]; I noticed in particular > one of the wires had a capacitor spliced in, was this a recall or > To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/