I have engine codes p1122, p1126, and p1128. My car will only go into limp mode when it's sitting for more than an hour or so with the car off. I have to reset the ECU using the accelerator pedal before limp mode will go away. We've ruled out a few things like fuse, relay, etc. Wondering if it has something to do with the braking system, due to the lights showing?

EDIT: Car is a 2005 Nissan 350z with about 125k miles on it! Today, we took the relay out and cleaned off the severely corroded terminals. Our reader also showed "Throttle relay" as always on, when we had the key on. I wasn't sure whether or not that was supposed to always be on or not.


Thanks everyone!

 

There was an article that covered this problem in a trade magazine recently (I can't remember which one at present) in which one of the writers suffered the same problem as you have described. After much testing and head scratching he found that there was a sealing grommet missing at the TPS sensor end, not the ECU end and this was causing the CEL to come on along with intermittent limp home mode. He fitted a suitable grommet and went through the throttle pedal relearn and then idle relearn and all was back to normal. As you have mentioned your relay was heavily corroded, maybe you also have corrosion and/or damp entering the TPS.