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1G ECU seems perfect. Car won't start

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Grose1

Proven Member
34
5
Aug 26, 2021
Setúbal, Europe
Hey Guys!

From everything I've seen before, my ECU seems perfect.

In fact I bought a 1g Eclipse with the 4g63 NA with the engine blown. Then bought a new engine and get it inside. The engine worked once, but after the radiator change (seems not related), the MPI fuse blown once and now it doesn't start at all.

Compression is OK in all 4 cylinder.
Spark plugs work fine.
Engine is timed.
Fuel pump is new and working with correct pressure.
CAS is new and the outputs are giving 4x per rotation 5v and 2x per rotation 0.2v (this doesn't seem ok), but injection is working, all 4 injectores look good.

I've been searching for everything but nothing works.

Last chance was to take out the ECU to check if it's good.

The engine worked fine, then started misfiring and working only 1 cylinder, and now won't even start...

Any help?

Thank you all








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That video shows it starting but you are saying that it wont start? explain.
Sorry, the thread comes from where the car won't start. Now it does but only stands for those 2-3 seconds and then shuts.

One particularity is that I can get that engine running only if I invert the CAS disk
 
Can you confirm that your fuel pump is staying running as the car shuts off? if the ecu does not see a valid crank signal from the cas it will shut the fuel pump relay off.
 
Can you confirm that your fuel pump is staying running as the car shuts off? if the ecu does not see a valid crank signal from the cas it will shut the fuel pump relay off.
I think I need to figure out some way to do that. Indeed the ECU is not receiving the correct signal - gives me code 23 so CAS, however doesn't makes sense for the engine to misfire and pop from intake with the correct timing and position of CAS sensor or am I thinking wrong?
Regarding what you said, maybe I can confirm if the fuel pump is turned of by the ECU listening to the MPI relay inside the car, right?

if everything was right, it should keep on for like 1 ou 2 seconds after I turn the ignition off, right?
 
Fault 23 is for the TDC (2 inner slots) sensor.
Fault 22 is for the Crank Angle Sensor (4 outer slots) sensor.

So there is a problem with if or how the TDC signals is being received by the ECU.
 
Last edited:
Fault 23 is for the TDC (2 inner slots) sensor.
Fault 22 is for the Crank Angle Sensor (4 outer slots) sensor.

So there is a problem with if or how the TDC signals is being received by the ECU.
It makes sense because I have the disk turned upside down and the TDC signal is inverted, so it gives me 23 code and turns off the fuel pump, so the engines shuts down. I don't have in mind any solution for this, since when I install everything correctly the engines doesn't works fine...
 
Are you checking and clearing the codes from the ECU between tests?
A 23 Code causes the ECU to not fire the injectors.

It's been a long time since I've taken a CAS apart, how do you know which side is up?

The signals don't get inverted but the relationship between them changes when the disk is flipped.
 
I've just performed tests right now. The fuel pump only goes off by the MPI fuse after the engine shuts off. You have uploaded some images from some manual on another post, that say which is the correct rotation of the CAS disk. I'll go from the beginning now and try to get everything timed. Disk correct and CAS times with the engine using the marks.

You can see clearly by the lines and the alignment of them which is the correct.

As said before, I will now perform tests and this time, as you advised, check for the ECU codes between them. I'm right by the car so I'll update you soon.
 
Well guys... I'm gonna just show you the below vid. It's working.

Thanks you all for everything. The journey is not over but at least it's working!
After many and many tries, I saw 2 spark plugs were fully wet and as these were new I tried to clean then and see if they were ok but no spark was coming out, so I changed them to 2 old sparks plugs. The engine got just a bit better. Came home and picked 4 old spark plugs from my Miata, changed them and the engine runs ok. Idle weird but runs ok.

 
Your weird idle is called idle surging.
I've been searching awhile about that... Maybe I'll start by a FIAV bypass and aí live in Portugal and we have temperatures between 5 and 35 °C maybe it'll be not that bad... No errors on ECU so I think all sensors are ok
 
I've been searching awhile about that... Maybe I'll start by a FIAV bypass and aí live in Portugal and we have temperatures between 5 and 35 °C maybe it'll be not that bad... No errors on ECU so I think all sensors are ok
Do boost leak test... there is unmetered air getting in somewhere.
 
You can still pressure test an NA, you just start at the TB instead of the Turbo inlet and you don't have to use much pressure. Expect the PCV to leak since it doesn't have to seal on an NA.
 
Ok so I did something. First thing was to block the FIAV. I still use the IAC but closed the FIAV spring. Car is now stable idle but holds at 1000 rpm. The thing I don't know how to adjust is the BISS screw (which was fully closed) and the throttle stopper screw (?you call it SAS?). Some air ir surely going there without me knowing. Fully closed BISS and without the stopper (fully closed throttle), it sill goes at around 1000 rpm. But now is stable and much better.

The problem now is the clutch. Does someone has a photo of the clutch fork and the slave cylinder? Mine seems too further and the slave cylinder is pushing it but the car doesn't unclutch. Might be the flywheel bigger or different from the other engine? I'm really confused but the clutch spring plate, when installed was too straight. Can't explain better but when torquing, it got with the blades straight. Will for now remove the gearbox

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Ok so I did something. First thing was to block the FIAV. I still use the IAC but closed the FIAV spring. Car is now stable idle but holds at 1000 rpm. The thing I don't know how to adjust is the BISS screw (which was fully closed) and the throttle stopper screw (?you call it SAS?). Some air ir surely going there without me knowing. Fully closed BISS and without the stopper (fully closed throttle), it sill goes at around 1000 rpm. But now is stable and much better.

The problem now is the clutch. Does someone has a photo of the clutch fork and the slave cylinder? Mine seems too further and the slave cylinder is pushing it but the car doesn't unclutch. Might be the flywheel bigger or different from the other engine? I'm really confused but the clutch spring plate, when installed was too straight. Can't explain better but when torquing, it got with the blades straight. Will for now remove the gearbox

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Well it seems that two lockwashers were need in the pivot point... I have removed 3 times the gearbox...3 times to find this out!!
 
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