Hi Scotty, First, I really enjoy your how-to videos. I have learned a lot from them. I have this issue with my 1993 Lexus SC400 1UZ-FE engine NO CODES/engine light
1993 Lexus SC400, Manual Trans, 140,000 I have had the car since 1998 brought with 77,000 miles had all maintenance done at the dealer until a few yrs ago with 120,000 mi. I smelled fuel in the cabin, research videos, and Lexus Forum. So, I changed the charcoal canister, had the solenoids in the ECM swapped that didn’t solve the problem, read up on the EGR valve, cleaned it out (carb cleaner), and swapped it with another one.
I started the engine afterward, and it will not stay running unless you maintain your foot on the gas; I changed out the IAC valve that didn’t solve the problem either. I have had two Master MECHANICS look at it with no resolution or fixes. I have run out of options, and you have no other videos I can troubleshoot with, so I decided to ask your advice.
Do you know the EGR you swapped out was good?
Yes the EGR was a good one, I swapped out both parts with two different ones and I even mixed and matched a couple of times and I still can't seem to get it to run without applying gas constantly, someone said the computer may need to be reflashed. I tried to reset by disconnecting the NEG for 24 hr and also touching the NEG to the POS to try to reset. Lost and confused now.
Has anyone tested the wiring going to the IAC valve to make sure it's getting Power on both terminals and the computer's Grounds are reaching it to control it?
In your case you don't have to test the wiring if you still have the old IAC valve motor laying around.
Pull the wiring connector off of the new (installed) one. Attach it to the old IAC valve motor and see if it's being controlled when you start the car.
If it is, then that answers that question.
When I first tested the IAC with the old one, I didn't hear the IAC engage, but when I swapped it out and turned the ignition to the on position, you can hear the IAC click on, but I will remove the wiring and test it with the old one again
Hi all, did some more reading up on the issue and was wondering could the ECU cause the problem of starting and not continuing to run? If so can you have the ECU flashed without being in the car, the Lexus dealer is a pretty good ways from me and Toyota doesn't want to work on it.
Thanks to all in advance for all the information you have provided.