Early EDM non-cat 4A-GE 16v Bluetop Fails emissions (high co)

[Bean]

If you already opened the ECU check that the pin out diagram you use is correct with what is written on the PCB (Toyota did some small changes). Then jumper the pins on the ECU instead of the diagnostic port to exclude faulty wiring.

Not a proper solution but considering you have an adjustable FPR lower the fuel pressure slightly and see if it helps at all with you emission problem.



Good luck

Maybe jondee can add his 2cents he has a nack for diagnostics across the globe.

[Rascal21]

As I mentioned I did lower the fuel pressure to minimum factory specs, it helped with about 0.3% only.
I`ll open the ECU again and make sure.

Again thanks for chime-ins everyone

[Bean]

the ECU part is related to the check engine light anyway so not related to the problem but might help.
Not sure where you read 2.4bar in the manual. In mine on page FI68-69 it sais 2.7-3.1 bar with the vacuum hose disconnected and 2.1-2.3bar with it on at idle (which is the important part for emissions).

PS: also check page FI96-97 and see if you get nearly correct readings on your sensors

[ditn]

0.8 thats reallly rich ...
Did you change map sensor already?
grey is the correct colour i believe 182cc

[Rascal21]

Pretty sure the W-pin is correct, in lieu of other info I`m starting to think ECU is switching earth for W lamp (while the lamp gets constant 12v).
If the pin-out`s were wrong from the Early 4AGE pinout available online the ECU would not be getting IGN signal (From memory, 12v IGN on pins 7-14 and B+ on pin 6 whereas W is pin 13).
And you`re correct, 2,6 bar pressure is what I have it set at, and that`s what made 0.3% difference on CO reading.
Potmeter is good (but also tried another one with same resistance area, to no avail as far as emissions go, 0.3% over-all is all it can affect)
I did have problems with the water temp sensor a year ago, it was broken, so I had cold idle hunting, soldered wires to the pins and no problems with that since

Potmeter is good, have not checked water temp sensor yet (Which I assume is OK since engine is not hunting at idle when motor is cold).

0.8 lambda and up to and over 8% CO is crazy rich, its overfueling like mad, without giving me grief while driving, idling or anything.
AND plugs which dont even have 1000km on them let alone 10000km, still look normal!
If it was exhaust leak I`d be getting over 1.0 Lambda value (but no better CO)

Have no spare MAP sensor but the one I have works (disconnect = engine stalls)

And yes I did visually check and re-grind earths for EFI on intake+head to firewall+block to frame-rail again (And measured them).

[oldeskewltoy]

(05-12-2016 11:28 PM)Rascal21 Wrote:  AND plugs which dont even have 1000km on them let alone 10000km, still look normal!

THIS..... as rich as you say... and the plugs should be black......

[Rascal21]

Indeed, they have been used in another 4A-GE that once ran rich, so they have some black residue on them on unimportant places from back then but nothing crazy, these plugs are mint (and expensive )

[Rascal21]

Ok, went and picked up EFI parts that is for another AE86 that I bought (more on that later), same ECU, harness, sensors etc etc.
So thats the THIRD ECU swap on forum recommendations

Changed green water temp sensor (same part#), still runs rich.
Changed MAP sensor (same #), still runs rich.
Changed injectors (also grey 182cc same # as everything else I have), still runs rich.
Changed ECU (yep, same #), still runs rich.
Changed potmeter (..), still runs rich.

Timing, fuel pressure etc is all good, but as usual adjusting the potmeter makes no change to idle RPM or rich condition (whereas on that Portugese AE86 guys Youtube video, the one who had his car stolen, potmeter adjustment makes an immediate change on idle)

I had a look at fuel return, I`m using the old 2T fuel line for return to the fuel catch tank (around 3 or 4 mm inner diameter), can feel the hose that goes from FPR to return line pulsing a bit hard (then again I dont know what to compare to), so maybe return line is a bit too small?
Am I perhaps looking at too much fuel back pressure here?
Whats the recommended pipe diameter?

Oh, also changed harness, still runs rich
Fully charged battery (in case injectors dont get the correct voltage), still runs rich.

[totta Crolla]

Note to self, always ask if an engine in question is fitted to an originally equipped 4age AE86

[Rascal21]

Yeah we had that discussion before, remember
Should still pass emissions
It`s overfueling, not blowing up because it knows it`s not in an AE86 or something.
I`ll simply lean it out with the adjustable FPR until Lambda values are correct, and will at least know then if there is something wrong with the internals or not, if it gets above 2% still it could be valve seals/piston rings (but it will pass the 4,5% CO requirement for the car itself) or it could be completely fine (Below 2%), will update as follows, worst case scenario I actually have a worn engine head and will need to service it a little