1UZ-FE problems in a Cobra.

PARTS FOR SALE: Limited availability on EGR Delete Kits, Torque Converters and Supercharger Brackets. Email for info: [email protected]

Schnitzel26

New Member
Messages
14
I have a wiring video for that ecu as well. It was part of the wiring instructions I sell but released it publicly as its not a common ecu these days
Hi again,
I actually did watch the video, but as the car has been running for some time and this problem has just popped up, it didn't really help with the problem but I still found it highly educational. The mechanic wonders if you would have a known, good working ECM lying around for sale. I see you are just across the ditch. Cheers.
 

gloverman

Well-Known Member
Messages
3,056
Location
Hamilton. New Zealand
Yep. The one from one of my videos. Tested and started fine however I'm reluctant to sell secondhand ecus as they are prone to failing so they generally get a refab before Ill sell them.
 

Schnitzel26

New Member
Messages
14
Yep. The one from one of my videos. Tested and started fine however I'm reluctant to sell secondhand ecus as they are prone to failing so they generally get a refab before Ill sell them.
Thanks for the reply. I understand your reluctance to sell second hand. I always told my customers that I can do a cheaper repair with used parts but no warranty. What sort of money would we be looking at? Also, shouldn't the MIL output from ours work? Someone has removed the wire from the plug, and I am not getting anything if I hook up the pin on the ECU connector.
 

gloverman

Well-Known Member
Messages
3,056
Location
Hamilton. New Zealand
In the video I diagnosed a faulty ecu that didnt have a CEL output. No CEL is a fail for the ECU. I did a video on ECUs as well. I opened 5 secondhand ecus and all had leaking caps , this is how often they fail so chances of getting a stuffed second hand ecu is very high. Especially if they have been sitting for any amount of time.
 

361UZ

Member
Messages
167
Location
Canberra ACT
Thanks for the reply. I understand your reluctance to sell second hand. I always told my customers that I can do a cheaper repair with used parts but no warranty. What sort of money would we be looking at? Also, shouldn't the MIL output from ours work? Someone has removed the wire from the plug, and I am not getting anything if I hook up the pin on the ECU connector.
See the video. The light should be ON with ignition and go out when the engine starts, unless you have a fault that has set an error. To see the error, link T1 and E1 on the diagnostic connector...
(You dont have one) so, T1 is pin 15 of the 16 pin ECU connector (Blue/White), E1 is ground. The check engine light goes between W, pin5 of the 22 pin ECU connector (blue/yellow) and Ignition. So when T1 is grounded, the ECU spits out engine error codes.
As Kelvin demonstrated, you CAN have an ECU that starts and runs the engine but wont give error codes. (I learned something more today!).
 

Schnitzel26

New Member
Messages
14
Thanks again, guys. As an electronics tech, and not an auto electrician, I have replaced ALL the caps in the ECU, and the fusible resistor going to the relevant CEL output pin was open circuit. I checked again today having opened up the ECU and plugging it into the vehicle, and once again, there was absolutely no output from the CEL or MIL as it is called in the manual. I have tested, as has the mechanic, had all engine sensors either checked or replaced, (bit of a fishing expedition, apparently), and as I said in an earlier post, a couple of auto electricians that just made things worse. The car will start and run fine, rev to the red line, for as long as it feels like, and as soon as you actually put it into gear and try and drive it, it just dies in the butt, won't rev, stalls etc. I still think it's the ECU, but I will double check 361UZ's suggestion, as that helps.
Gloverman, apparently the owner wants the car to remain as is, with this motor, so what would it cost for a known good refurbed ECU. I know you can't give a warranty on a secondhand unit, so that is up to the customer.
 

361UZ

Member
Messages
167
Location
Canberra ACT
Interesting progress. An ECU WITH a working checking system would be a must, even if the problem with the car is something else. Its the only sure way to see what the ECU thinks is the problem.
If I was your friend (and I might be in the same boat one day) I'd be exploring alternate ECU's.
You said its in a Cobra replica. Plenty of those around, so plenty of ideas about alternate ECU's, Toyota or aftermarket.
But I know its frustrating, and being an electronics tech (as I am/was, I.T mainframes) you'd want to nail the actual faulty component, rather than throwing parts at it till it goes.
 

Schnitzel26

New Member
Messages
14
Interesting progress. An ECU WITH a working checking system would be a must, even if the problem with the car is something else. Its the only sure way to see what the ECU thinks is the problem.
If I was your friend (and I might be in the same boat one day) I'd be exploring alternate ECU's.
You said its in a Cobra replica. Plenty of those around, so plenty of ideas about alternate ECU's, Toyota or aftermarket.
But I know its frustrating, and being an electronics tech (as I am/was, I.T mainframes) you'd want to nail the actual faulty component, rather than throwing parts at it till it goes.
Hi again. This car has been sitting at the mechanic for a year now! The mechanic (Wayne) tells me EVERY sensor has been either tested or replaced, but I have my doubts. The ECU was apparently sent to some place on the mainland called Jet Tech or similar, and supposed to have been tested as OK, but I really can't see how they would test it without an actual motor. Even Gloverman in his video shows it starts and runs, but what does it do when you actually try and drive it? Wayne tells me ECU's are available from S.E. Asia but they have a completely different plug setup, which of course would be a major pain. This car was built ten years ago and the wiring loom was sent away with the computer to be modified to suit the Holden Torana dash etc. I have no idea what sort of manual box is in it, and Wayne tells me the owner wants to keep this motor and he is also reluctant (Wayne), to change it, as it would require major mods to the Torana chassis, steering, etc. The 1UZ has been shoehorned in as it is. I am a cancer patient and can't spend all day on these things, but I will go out again today with your suggestion and bridge those pins and see if there is any sign of life. As for a refurbished unit, I mean all one could expect is that the caps have been replaced, all passive components checked, and all semi's checked for shorts, which I have already done, as well as resoldering the entire boards. There is no reaction to heat or cold, and wiggling all the wiring doesn't change things. Everyone who has looked at the car has just thrown their hands in the air and said it was too hard, but I am like a dog with a bone and like to see things sorted. An actual circuit diagram of the ECU with the functions of all the IC's would be fantastic, but the, even the MOSFETS are listed as unavailable (they check OK.) I will keep everyone informed as the saga continues. Cheers.
P.S. The ECU is behind the front firewall of the passenger seat, and would cop a fair bit of heat, but I haven't been able to find any components that are getting hot. Obviously, if I can get the checking system to work, it will throw quite a few codes as a lot of things haven't been connected.
 

361UZ

Member
Messages
167
Location
Canberra ACT
" Obviously, if I can get the checking system to work, it will throw quite a few codes as a lot of things haven't been connected. "

But presumably the battery is disconnected between testinmg sessions, so hopefully any unintentional codes should be cleared.

I am a bit like you in the dogged determination ti find the actual problem, but there must come a time when a different ECU would be easier and cheaper. (AND a bit easier on you!).
I am in Canberra. My test bed is my 36 Chev. As I said before, my ECU seems to work ok. At the present stage I have been looming the wiring up and sorting out where the various controllers will go (these Crowns had a LOT of controllers!).
But I could test your's for you if that helps. Only cost would be postage to and from. My wiring is all standard, I have deleted wiring for stuff I dont need, but what's there is 100% Toyota.
 

Schnitzel26

New Member
Messages
14
" Obviously, if I can get the checking system to work, it will throw quite a few codes as a lot of things haven't been connected. "

But presumably the battery is disconnected between testinmg sessions, so hopefully any unintentional codes should be cleared.

I am a bit like you in the dogged determination ti find the actual problem, but there must come a time when a different ECU would be easier and cheaper. (AND a bit easier on you!).
I am in Canberra. My test bed is my 36 Chev. As I said before, my ECU seems to work ok. At the present stage I have been looming the wiring up and sorting out where the various controllers will go (these Crowns had a LOT of controllers!).
But I could test your's for you if that helps. Only cost would be postage to and from. My wiring is all standard, I have deleted wiring for stuff I dont need, but what's there is 100% Toyota.
Thanks so much for that, I tested it once again per your suggestion, and nothing worked. We are convinced the ECU is U/S so now on the hunt for a replacement. I think this particular case is one where there have been too many cooks in the kitchen, all with different ideas and dodgy work. Cheers.
 
Top