DIY: Hopeless project.

[Ivan141]

Yes, that would be the obvious conclusion.
either the fuel line or filter is clogged, or the pump is not operating properly.
Find out how fuel comes out before the filter, then check the flow at the pump
end of things.. not a nice job, but you'll have to single out the cause.

[Rascal21]

(07-12-2015 07:02 PM)Ivan141 Wrote:  Yes, that would be the obvious conclusion.
either the fuel line or filter is clogged, or the pump is not operating properly.
Find out how fuel comes out before the filter, then check the flow at the pump
end of things.. not a nice job, but you'll have to single out the cause.

Not afraid of getting a little gasoline on my hands, plus "4A-GE powah" (the power to make you smile) is worth the trouble

Never had problems with low fuel pressure before, so it`s a learning experience.

I took off the fuel pump hose that goes to the fuel pipe, put it in a bottle and tried the pump again, just like it did at the fuel rail, fuel just calmly filled up the bottle instead of shooting it away, the fuel looks very good though so I`m probably looking at a fuel pump gone bad.

Maybe a pump with a little more pep could be a nice insurance too.


No wonder it ran rich the last time I got it started, I can imagine the fuel pressure reg was probably trying to compensate for low pump output which has now gotten so bad theres no way in heck I`m going to get her started until I change the pump.

[Ivan141]

Time to drop the fueltank then..
For a 4age I'd recommend getting a decent OEM pump, not a Walbro (chinese fuel heater).
Lot's of period JDM in-tank pumps fit reasonably well... I was running an RX7 FC turbo pump on mine.

[mad.matt]

I've heard R32 GTR pumps are a good OEM upgrade

[Uzelac]

No need to put more stress on fuel and system, get an OEM speced pump from reputable manufacturer.

[Rascal21]

Followed your advice and bought a new cirka OEM spec pump from reputable manufacturer, 5 bar and 100lph, costed me 300E but whatever, I can just bring it back if it breaks etc.

Fuel pressure is back, but new symptoms appeared:
No spark, and plugs are not wet (Maybe theyre not supposed to be? They do smell fuel)

Tried a set of brand new Bosch plugs, the set of NGK`s that I`ve been using, AND the Denso set that was in the engine when I bought it, all of them seem fine but alas..

Now and then it sounds like she gets spark i.e a single cough, but she wont start or anything, I get RPM signal though, so I suppose igniter is good?
Test light on W-pin with diagnostics bridged shows nothing.

Just to have it covered I made new earth for the coil/injectors/ecu on engine intake, and to be sure I made a new harness with new 12v relay for coil and injectors from ignition, but the symptoms prevail.

Again I checked resistance on coil, plug wires, dizzy cap, rotor, tps and most other components covered by the manual, and also made sure the distributor was centered on marks with engine in TDC, compression is good also.
As usual, all components are apparently well within OEM specs.


Edit: Tried filing the Coil bracket and engine bay metal shiny where both contact, in a bid for good earth, but alas no cigar.

Reverted to old alternator (I`ve tried a 20v alternator in it in hopes the voltage might be bad, no difference though), still wouldnt start.

Changed fuel pump to the one I currently have, still wont start.

Reverted to old coil and igniter, still wont start.

I even kicked one of the front tires and spun around 360 degrees for extra rainbow tofu luck, still wont start


So no ECU codes, but no spark, no fuel to cylinders.

This all started with me leaving the car at home for a month, coming back home and started her she worked perfect, but as she got warm, the idle went super-low and she stalled out, started her back up and did my round around town the ignition got worse and worse, barely limped back home on super bad Rotary style ignition.

Then I changed coil+igniter for another 2nd hand item, she worked for a little but was running super rich, I passed my house on the way home after a test ride and she stalled further up the hill here, I managed to roll back home thanks to gravity.

After that I could start it sporadically (every time I started was because I made new earth here or there, changed ignition items here or there etc, now all ignition components are new except coil and igniter) and in the end she wouldnt start even when I reverted the changes I made etc.

As I mentioned, I went over to a 20v alternator and re-did the alternator wiring, she still wouldnt start, so the next day I recharged the battery (Almost no voltage lost) and still would not start, then later that day she started like lightning out of the blue sky, she idled for 50 seconds, went down to 200 RPM, then back up, then stalled, so I restarted her, same thing, 50 sec idle, 200 rpm, back up, stall, I`ve never got her started again no matter what google/forum/top dollar advice I`ve followed.

Is there any way to use a multimeter to find out if igniter is bad?
I`ve tested the coil (and it`s VERY good according to manual) but ECU gives no Error code on Igniter.

[pack]

Have you checked the grounds of the ignition coil?

Forget the ignitor and focus on the coil!

[Rascal21]

(07-20-2015 10:39 PM)pack Wrote:  Have you checked the grounds of the ignition coil?

Forget the ignitor and focus on the coil!

Alright, how can I check that? Where does the coil ground lead to and is it always grounded or do I have to leave ignition on? Do I make a lead from coil negative to fender?

I`ve filed the grounded eye-spade connector on the intake for ignition/ecu/injectors and made a lead from there and to the fender if thats what you mean, I also filed the coil bracket where it contacts bodywork, as well as the bodywork (where it contacts the coil bracket..) alas both to no avail.
I dont know where else coil ground might be.

[Rascal21]

Tried another few coils I had laying around, 1 from 2T, 1 from 4AC, and 1 random (don`t know what brand), still no spark, all of them checks out better than minimum OEM FSM specs as far as resistance though.
Tried a wire from ground on coil and to intake, still no spark.

I think it`s safe to say that the 2nd hand igniter I got was also on it`s last legs, no other way to explain why this problem persists.

Found that all the 88-89 MR2/SR5 Pickup etc igniters are replacements for the 12270 (MAP) igniter, so I found a cheap enough one for around 150 dollars or something, I`m not all that worried it wont be in sync, read about one guy using Celica igniter on a otherwise stock MAP motor too.

[pack]

Damn.... electrical problems sucks balls..!