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Hey guys, long time. First of all, apologies in advance for the length of this post, just thought I should provide as much detail as possible. I'm having some starting issues and I guess I'm kind of running out of ideas, so if anyone has any ideas, i'm all ears.

1990 Mirage Cyborg with a 4G63 swap. About a year and a half ago I was daily driving it, I got in the car one day and went to start it, and it just cranked continuously, didn't fire. I sat there for about 10 minutes trying over and over, my battery was going flat and I was just about to phone a tow company, when for some reason I decided to roll the car. So I pushed it backwards a few meters, and tried to start it again, and to my surprise, it fired right up (still can't figure that one out). From memory this exact thing happened again twice, and ever since then, it hasn't started at all, regardless of if I move the car or not. I was kinda over it at that stage, and I have 2 other cars I can drive, so I parked it up where it has sat unloved for the past year or so.

Prior to this happening, I had a different weird starting issue. Often when I started it, it would attempt to fire on like the 1st or 2nd crank, and either immediately die, or sit there struggling at 200 rpm until I kicked the gas. If it died, the second time starting it would be more difficult, it'd crank over for about 5-7 seconds before it actually started, as if it was flooded? From memory the car was doing this for over a year. It never seemed to get any worse during that time, just randomly happened sometimes and other times it'd start fine.

I'm not sure if the two problems are related, but I thought i'd put them both out there.

Now I've decided I miss driving it, so I wanna get it up and running again. Back in 2009, I did an engine bay wire tuck. I decided to start there, so I pulled the harness out and went over it. I found that the CAS wiring didn't look the best (didn't have a soldering iron at the time when I did the wire tuck so I crimped the connections), a couple of the wires were sitting loosely in the crimps, barely connected. So I pulled all the crimps off and properly soldered the wires together. The rest of the harness looked fine. At this stage I was pretty sure I'd solved the problem, so I went and put the harness back in the car, turned the key, and the same thing happened, just cranks over and over.

I pulled the spark plugs out to check if I'd flooded it. Nope, dry as a bone. Checked the ECU for leaking caps, all seemed fine, no visible leaks, no fishy smell. The car is getting spark. The MPI relay clicks when I turn the key, but I have no idea how to properly test it (might just see if I can find a 2nd hand one to try, but from what I've heard, if it's clicking it should be working?). I ran out of daylight, but next on the list is to remove the fuel line at the rail inlet and give it a quick crank to make sure fuel is getting to the rail? I'm electrically retarded, I own a volt meter but I don't really know how to use it. What should I be testing? I'm guessing if the fuel is making it to the rail, I should be testing the injectors, if it's not getting to the rail, I should be testing the fuel pump?

I just remembered, about 7-8 months ago I did attempt to start the car, and it actually did fire, but died immediately. It hasn't fired since. Is there anything obvious or simple that I'm overlooking? What should I do from here?

Thanks in advance

Edit: Another thing I just remembered. Every time I go to start it, I get the rapid clicking that you get when you have a flat battery, only for about half a second, and then it proceeds to crank over like normal. This is with a brand new battery. I might actually try hooking it up to another running car and jumping it, but like I said, it cranks over fine. Can this be a sign of something more sinister though? Bad earth maybe, poor power feed to battery? Anything at all that would cause the car to not fire??

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1990 C83A 4WD 4G63T powered hatch - [PSIBRG]
1992 JZX91 2JZ powered Toyota Mark II

Do you have a known good ECU to try? I've seen ECU's that looked mint be bad and I've seen really bad looking ECU's work. It's weird but that's where I would start.

If that checks out find the fuel pump check connector (if you didn't eliminate it) and make sure its working.

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93 Mitsubishi Expo LRV 1.8/manual
95 Eagle Summit DL Coupe 1.5/manual
01 Mitsubishi Mirage ES Sedan 1.8/manual

I would check for fuel at the rail first..sounds like it could be not getting gas.




Steve

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Steve 89 colt 2.3 stroker stock top end. evo3@20 psi 13.489@99.30mph 3/10 2012
On drag radials.auto trans.launching @ 5 psi and no traction thru 2nd.

Since you messed with the wiring I would check the grounds for burns. You could open your ECU like Mirageman said, cause that could be the issue too. If the car sat for a long time, get rid of the fuel and add some fresh petro. Also check your battery post-these are ideas that im tossing out for you.

Thanks for the suggestions guys, feel free to keep them coming
I don't have a spare ecu, but I'll post up on the local forums and see if I can find one to borrow. I run a Walbro pump, I made sure when I bought it (4ish years ago) that it was genuine, so I doubt it'd be dead, but who knows, worth a look!
Thanks, this was gonna be my next move anyway, I'll try do it tonight if I get the time.
Alrighty I'll check the grounds out. I've opened the ecu and it looked fine, but I'm gonna try to borrow one off someone just to be sure. Looks like I might be dropping the fuel tank to get at the pump, so I'll put some fresh gas in while I'm at it. Thanks for the ideas!

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1990 C83A 4WD 4G63T powered hatch - [PSIBRG]
1992 JZX91 2JZ powered Toyota Mark II

When was the last time you replaced the coolant temperature sensor?

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go fast- break stuff- repair- repeat

Engine starting, after cranking properly, then stalling almost immediately likely spells out just enough fuel to push into the cylinders but not enough pressure and or volume to keep the engine running.

There is a check wire on the firewall that allows you to apply a positive feed direct from the battery and should turn on the fuel pump.
Is your fuel pump rewired yet? or still stock all the way to the pump? Aftermarket fuel pump?

If the starter makes a fast ticking noise like a weak source voltage/low current supply, and then stabilizes ... you can have a weak Bendix function (there is a pull in winding wire that is the wire you trigger with your key forward the push on connector to the top of the starter) or a even a bad Bendix. This is what is likely happening to my car, key forward in crank and nothing but a loud clank from the Bendix function operating but no starter movement. Try again 45 minutes late and voila, it cranked and started without issue. Check for poor terminal tension when the connector removed/installed and green death in the connector and pin on the starter.

If the engine fails to crank over, you can have someone get in and crank the key and you can confirm the power supply to the starter Bendix with a test light. If you have a properly lit test light, then you should have enough current to get the Bendix moving. After that, you are looking at starter replacement. Don't worry as all the starters 4g6X motors are the same in this regard (within a few watts of one another), the only difference was the starter plate moving them to the proper nose position for the flywheel they were going to mesh with (AWD and FWD bellhousings).

There is a connector on the right frame rail near the fuse box (RF) that connects a black wire with yellow stripe (the wire that goes to your starter Bendix) and that connector can get pretty green. So, sadly there are two points of failure just on that section alone, to provide distress to the starter engage/hold-in function of the Bendix.

I just had those cleaned up while going over my wiring and alas, I am where I am. Once the car needs to drive, I will test wiring and pull out the AWD starter that sits in my basement. If my starter is indeed original, it has nearly 200,000 km's of starts behind it.

Thanks for the detailed reply Mr Eagle. I haven't had enough time to even touch the car during the week but I'm gonna see what I can do tomorrow if the weather holds out.

Where exactly is the check wire on the firewall? Like I said, i'm partially wire-tucked, so chances are I might have gotten rid of the check wire. Hopefully not. The pump (Walbro 255lph) isn't rewired yet. I'm hoping it's a dead pump tbh, cause I've been wanting an excuse to buy a Bosch and do the rewire.

Another thing, is my fuel filter looks like absolute crap. I've never changed it since I've owned the car (a long time now) and I kinda doubt the previous owners did either judging by how the thing looks. I've ordered a new one, though I doubt it will solve my problem cause I can't imagine the current one being completely blocked to that extent, but hey, it's gotta be done anyway.

The starter issue was non existent when I parked the car up, so I'm thinking it'll be something minor like the battery not charged up quite enough? Possibly corrosion on a connection somewhere? The starter was brand new about 5 years ago.

But yeah, this has definitely given me some ideas to go on, here's hoping I can get the old girl running again.
On this engine, never But I always thought the coolant temperature sensor affected hot starts, I remember having a temp sensor issue on my old 4G61 and from memory the car would start up perfectly fine when cold, but that was years ago now so my memory is a bit foggy.

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1990 C83A 4WD 4G63T powered hatch - [PSIBRG]
1992 JZX91 2JZ powered Toyota Mark II

Check wire may be on the right side of the firewall for you, but for us it is on the left. Single prong female connector just like the one that clips onto the starter.
It's still in your loom somewhere.

Fuel filter is a great idea, Also probably good to drain the fuel rail also which may happen when you disconnect the top line from the fuel filter, as gravity will take over most of that. If you wanted to help it along, you can jack up the car on the left (passenger for you) side (preferably a suspension point and not the pinch welds!) to aid gravity bleeding almost all of the fuel back to the filter line.

Weak battery ... yup that plagued me when I went to first start my motor after the tear down. Just went weak sauce from sitting and not being charged for months on end.

Either boost it, or have it tested. Either way be weary of a battery 3-5 years old and that hasn't been taken care of. Sulphation ... the silent killer.

So, confirm with a check light or light bulb wired to ground, that when you crank the engine, you can light the bulb with the other end of the tester plugged into the starter connector (small black push on style). At least you know you have power that far. If not, work your way back.

Get it cranking and running and go from there. Fresh fuel never hurt, and you could use another running car to get the fuel check connector operating and pump out all the fuel from the tank. This saves pushing it up through the injectors/combustion chamber, etc. Just wait to change the filter in that case or use the line right off the bottom of the fuel filter to drain into a large plastic pop bottle container. Be very careful of fumes ............... Sparks ............ this may not be the best idea afterall ..... Sigh. Well, even with a near dead battery you could do this with some test wires and not have fumes anywhere near the fuel. There is always a spark if you are connecting/disconnecting wiring unless there is a switch inline.

If the ECT(engine coolant temperature) has failed and is telling the ECU that the coolant temperature is -70* then you aren't gonna start whether it is hot or cold. Not sure if you have link or access to a scan tool but that is easiest way to find out what the ECT is reading. Or you could always replace the thing with a new one...

Interesting, something to keep in mind for the future, but it's not related to my current problem.

I managed to finally find some spare time on a fine day so I did a bit of work on the car. Pulled the fuel line off the rail inlet and cranked it over, no fuel came out. I poured a bit of fuel into the rail and the car fired right up, so my problem is definitely a lack of fuel reaching the rail. I pulled my old fuel filter off, but decided I'll grab some new banjo bolts and copper washers to go with the new one, so I'll sort that out later.

I managed to find the fuel pump check wire, but didn't have any spare wire kicking around to run power to it so I'll do that sometime in the next few days. Hoping for a faulty fuel pump as it'll give me an excuse to upgrade to an in-tank Bosch. If the fuel pump and it's wiring/connector end up being ok, what would be next on the list to check? Still have to find an ECU to test out I guess...

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1990 C83A 4WD 4G63T powered hatch - [PSIBRG]
1992 JZX91 2JZ powered Toyota Mark II

If you put a load like a test light inline from the power supplied, to the ground wire both of which are in the fuel pump connector, then you can confirm MPI relay operation and all wiring back to the tank. If the light does not light, choose another ground location to put the test lead, while still probin the power pin, if the light comes in when tested, you could have a bad ground (confirming once again the power side feed to be good). Always check the test light before making connections to confirm it still lights up period! Self check.

If power supplied via the fuel pump wire on the firewall, and confirmed ground at the pump, but no pump action ... Drain the tank via the bolt on the base of the tank, also a good time to invest in a quality drain pan! Likely dead fuel pump ...

Be warned not to start a fuel pump outside of the tank!!!!
Residual gas can light off .... = BAD.

Thanks man, I'll see what I can do over the next week or so!

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1990 C83A 4WD 4G63T powered hatch - [PSIBRG]
1992 JZX91 2JZ powered Toyota Mark II