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Ok I got the "new" used MAF sensor in, installed same, then removed negative battery cable for a of couple minutes, replaced cable and fired her up. Still had check engine light Ran diagnostics, no longer a code 24 but still flashing a code 31. About that time my buddy called to tell me the "new" used HVAC screen was in and to come on down and he would put it. I hopped in the sc400 a headed to his lot. As i was leaving the neighborhood i came to a slight incline and goosed her just a little. THE LIGHT WENT OUT, when I backed off the light CAME BACK ON.
It appears that light will go off anytime the engine is placed under just a slight load. In other words anytime the engine demands more air the light goes out.
Ideas PLEASE
Thanks much for the offer to assume the role of sounding board. This something i need quite often. you've figured out I'm in Southaven, just across the line from memphis and the name is Bill Ham. Where are you Rodger.
Please take look at my last post regarding the check engine light issue. I just posted a few minutes ago.
Thanks much for the offer to assume the role of sounding board. This something i need quite often. you've figured out I'm in Southaven, just across the line from memphis and the name is Bill Ham. Where are you Rodger.
Please take look at my last post regarding the check engine light issue. I just posted a few minutes ago.
I can't offer any suggestions on the 31 code. Have not ran into that before.
I would however not rule out you may have a problem with the ECU. If it has not been serviced you probably should have that done. They have a known issue of leaking capacitors which is well documented on here if you want to read about it do a forum search. If it has not been done you run the risk of damaging the ECU from the leaking capacitors. You can send it to Tannin Auto and they will repair it and send it back to you for about 100 bucks.
Thanks for info about Tanin Auto. I'm probably going to replace the MAF sensor with a remanufactured one this week. What is so disgusting about all of this is that everything was just fine until the work on the AC was done.
Thanks for info about Tanin Auto. I'm probably going to replace the MAF sensor with a remanufactured one this week. What is so disgusting about all of this is that everything was just fine until the work on the AC was done.
I missed that earlier that you had a/c work done. The maf is right in the way of getting to the low pressure port so the guy probably moved it and could have broke a wire, messed up the plug, dropped the maf, etc. Might want to look the plug over closely. Maybe the replacement maf will tell you something. These plugs get brittle and a lot of times the snap breaks when you unplug them. But I am sure you looked at all of that.
Southhaven, I would also recommend checking your connector to the MAF just to rule that out.
What model year, engine type, transmission and emission type is your SC? In case you need it for reference here is a list I've compiled of *most* ECU's our SC300's and SC400's use just in case this is needed to source another. Frequently you can find these on ebay. In this situation is is also good to just make a WTB ad in the CL SC300/400 classifieds and reference the P/N on your original ECU to see if anyone might have the one you are looking for.
I will also echo the recommendation to get your ECU rebuilt by Tanin Auto. They do exceptional work and with few exceptions are able to restore your engine computer back to its original snappy condition. If they do find any issues that are irreparable they will be able to help locate a new engine computer for you.
Though all you should need to do is send the in the ECU in your car to Tanin (pack it well, throw on some insurance and use non-overnight shipping) and you will have it back in a week or so good as new. Sourcing another is only needed if you cannot afford the downtime without your car or if the ECU was proven to have an irreparable issue... which is rare to occur even if repair is needed.
At the age these cars are at due to the type of board capacitors Toyota/Lexus used in the middle 80's through early 2000's it is good policy for everyone to have their ECU refreshed with new capacitors (but very specific replacement types are required).
Tanin will take care of everything required when you send it in.
Congratulations on solving one of your two CEL codes!
I removed the MAF and air cleaner box today. Much to my disgust there was only ONE bolt anchoring the air cleaner box and MAF. The other anchor was the rubber tube connecting the MAF to the intake. the bolt attaching the metal strut extending down from the right side of the MAF near the windshield motor to the car body, was missing . Sloppy, Sloppy, Sloppy. I believe the check engine light came on shortly after I left the repair shop. I hope and pray the remanufactured MAF assembly solves the problem. If the problem is stil exists there is going to be a really nice 1993 SC400 for sale. Timing belt done about 10,000 miles ago in the summer of 2015. I don't need this aggravation at this late stage in my life. My wife was right .
Southhaven, do you need the OEM part numbers for another couple of air cleaner mounting bolts? Seems some mechanic did not put them back when they should have. Nonetheless you will be able to get these from any local Toyota or Lexus dealer.
They should be 90119-06467 (x3) or 90119-06667 (x3) for the main airbox. I believe there are only three main bolts anchoring it to the chassis.
For the connection between the MAF and airbox there are four (4) nuts: 90179-06195
...And the gasket should be 22275-50020.
It does sound like it's nearly in good order now. A 10,000 mile old timing belt is WELL within good service life.
The remanufactured MAF should help and getting another repaired ECU installed should help.
The correct ECU part number to search for on ebay if you just want to find a decent second one first and *then* send that out for repair is:
1992-1994 Lexus SC400 ECU 89661-24231 (Federal Emissions Type -- 49 States). 89661-24230 may be the same part number of the ECU that is currently in your car. They should be the same computers just with one number difference from Toyota.
If you have a 1993 California Emissions SC400 (doubtful but you should check the label under the hood just in case for "Federal" or "California") then the ECU part number will be 89661-24240.
Once you get your new MAF installed I really think you should also get either the ECU in the car rebuilt or get a spare ECU off ebay and get that worked on by Tanin Auto and reinstalled in the car before you write the vehicle off. You will notice a difference all around with a reconditioned ECU.
From what you've said so far the car is in good shape. The MAF and ECU in SC400's tend to be likely culprits when phantom issues show up and are both easily addressed to rule them out.
Somebody missed the deal of a lifetime. this time yesterday if some had made a halfway reasonable offer they would have owned nice SC400.
Got the remanufactured MAF assembly in today, a spent about a hour PROPERLY installing same. Just got back from about a 6 mile test drive...NO CHECK ENGINE LIGHT. The tiger under the hood purrs like a kitten
Congratulations, Southaven!! Very glad to hear this news!
Aside, I still feel getting your original (or a spare correct-part-number) ECU reconditioned is a good idea but it is always great to hear that an issue has been solved and the car is treating you well again!
KahnBB6, that's on my to do list. Right now I'm just going to drive around town for a few weeks grinning like a Opossum eating persimmons. Thanks for the parts diagram.
07-07-16, 01:44 PM
