1992 LS400 Ground Up Build
#77
Rookie
Thread Starter
So I picked up this ecu from ebay for like 15 bucks. It said good on it even though it was beat up pretty good. I replaced it in hopes of fixing my transmission slip. I do feel a significant difference in that when I come to a stop, it actually downshifts now and I can get out of the stop sign not in 3rd gear. I can also go up hills now. This is all staying in drive, obviously I can come out of stops and go up hills when I shift manually but when in drive, it usually doesn't work. But with the ecu swap, it works better. However, sometimes, I feel like on straight a ways, when I floor it, it goes from 1st to 3rd again but only when I push it, for the most part, it is driving better, not 100% but better. I don't know what else I should try and do to it though to try and check to see what is up with the transmission. Do you think it is the transmission itself? How would I diagnose that?
#79
Rookie
Thread Starter
So I have been struggling to figure out why my car won't rev past 2000 rpm when in drive mode sometimes. I finally got around to checking the codes with that little paper clip thing and I got the codes 25, 41, and 55. They correlate to Air-fuel ratio lean malfunction, Throttle position sensor signal, and No. 2 knock sensor signal respectively. I do not have the manual, does anyone know how I would be able to solve these problems? I have done some research and have read that I should replace the o2 sensors to fix the lean malfunction. But I could not find anything on fixing the throttle position sensor signal. Some people said that it is because I have a vacuum leak or an egr leak and if I fix those, the throttle position sensor signal will go away. Is this true? Any information will help. Thanks.
#80
Pole Position
I'd be a little suspicious with that ECU you put in there. Thing looks a little beat up. Never know what you're getting with those ebay ECUs, especially when ya get the cheapest ones. I had codes for the TPS and O2 sensors and also the car would die at 2k RPM in drive. If I revved it to 3500 RPM in neutral it would skip bad but wouldn't go any higher. It turned out being the ECU. (changed it yesterday) I don't think changing the O2 sensors would do anything especially since the code for the O2 isn't coming up on yours.
Also I notice on the beat ECU it doesn't have the small sticker next to the main part # sticker. It seems weird why someone would take that off.
Also I notice on the beat ECU it doesn't have the small sticker next to the main part # sticker. It seems weird why someone would take that off.
#81
Rookie
Thread Starter
I'd be a little suspicious with that ECU you put in there. Thing looks a little beat up. Never know what you're getting with those ebay ECUs, especially when ya get the cheapest ones. I had codes for the TPS and O2 sensors and also the car would die at 2k RPM in drive. If I revved it to 3500 RPM in neutral it would skip bad but wouldn't go any higher. It turned out being the ECU. (changed it yesterday) I don't think changing the O2 sensors would do anything especially since the code for the O2 isn't coming up on yours.
Also I notice on the beat ECU it doesn't have the small sticker next to the main part # sticker. It seems weird why someone would take that off.
Also I notice on the beat ECU it doesn't have the small sticker next to the main part # sticker. It seems weird why someone would take that off.
#82
Pole Position
I didn't realize you had the same codes with the old ECU. I don't know what your problems would be then. My ECU was bad, caps leaking. I think my problem was whatever cap dealt with throttle position cuz it's fine now. I notice you have those two sets of wires going to the sides of your ECU, do you know what those are for? Are they some type of relays? It might be a Ca. thing cuz I don't have them.
#83
Rookie
Thread Starter
I didn't realize you had the same codes with the old ECU. I don't know what your problems would be then. My ECU was bad, caps leaking. I think my problem was whatever cap dealt with throttle position cuz it's fine now. I notice you have those two sets of wires going to the sides of your ECU, do you know what those are for? Are they some type of relays? It might be a Ca. thing cuz I don't have them.
#84
Pole Position
On a side note; I just went through all the pics from when you started 4 1/2 months ago and would like to commend you on the progress and dedication you're putting into this car. Good job so far. I think I was the first one that said " it ain't worth it". But for you, doing it your way and on your time, I guess I was wrong, sorry. Maybe I just see things different now that I'm older, wish I was your age again.
#85
Pole Position
I was losing motivation to fix my LS. This post gave me some, love what you’ve done to your car.... especially the black accents on the door, and the wood in the trunk!
#86
Rookie
Thread Starter
I replaced the throttle position sensor(tps) because I was getting the error that the tps was malfunction, but it did not seem to help my problem. I think I am going to try and clean the egr valve next because I was reading and I saw that some people say that the reason I am running lean is because my egr valve is broken. And when I run lean, the car smells bad which it does, so I hope cleaning the egr will make the smell go away and maybe I will be able to go above 2000 rpm when in drive so I don't have to manually shift. I also replaced the air filter. Question: Will replacing the maf sensor help in anyway? Also, another question, when my car warms up to temp, in drive mode, I can't rev past 2000 when I floor it, I have heard that this is because I am in limp/fault mode and apparently I have 40% power, but when I manually shift, I can rev up to whatever I want, when I am in Low and second gear, am I at 40% power as well?
#87
Rookie
Thread Starter
I finally got back to the Lexus. I finally saved up some money to get some parts and as you can see I am doing the important mods first. I put two 12 subs in the back.
#89
Rookie
Thread Starter
My hood struts used to not work and I use to hold my hood open with a half broken fishing pole every time I had to jump my car. So I replaced the struts and now they work like a charm.
#90
Rookie
Thread Starter
Finally saved up some money and was able to do a real mod. The car no longer sqeaks and feels like a wheel is gonna give out every time I make a turn. I dropped it a bit but I don't know if I should go any lower. I know I could run a stretched tire and drop it a bit lower, closer to a fender to lip look but my rims I don't think are quite made out for that yet. Lmk your thoughts on how low I should go. I think I might try to do sum tire lettering on my tires and go for more of a track look than a vip look but idk. Maybe its just my wheels rn tho and when I get sum better wheels I'll try and go more fender to lip.