3TGTE issues

[Ta22boy]

Hey,
i have a ta22 running a 3tgte, but i cant get it to run right anyways it has a constant miss and wont let me rev the engine, but does slowly increase in rpm but still missing the whole time. The engine will start and idle very slowly around 250-300 rpm but once you try to rev it up and let it drop to idle it stalls. Also the engine is overfueling badly but i do have good spark also ignition and cam timing are both fine.I also need information on the three pressure switches, such as which one does what? and at what voltage should i read when they are in the off/on position?
i have already tried many things but the most recent are-
-disconnect the vacuum lines off the 3 pressure switches, with no effect
-disconnect all three wires going to pressure switches, and then engine wouldnt start after all were disconnected, then i re-connected one and it started and seem to run a lot better.

Anyways i am mainly looking for sugestions for things to try as i am running out of idea's...any help would be really appreciated

Cheers
Scott

[Ta22boy]

c'mon someone has got to know about these pressure switches

wheres all the 3tgte guru's?

[Hulk]

Hi Scott,

I was looking back through your old threads. Would this be the same or similar problem that you have been having for a while?

Here's my left-field suggestion.
I couldn't tell if youre running an aftermarket ECU, but if you have the standard computer - I would suggest unplugging it taking it to an auto leccy and just getting him to resolder the points on the circuit boards. Shouldn't cost much at all. Might take him an hour.
The stock computers are prone to dry/cracked solder joins (30+ year old electricals).
I was having a similar problem and that's all it was!


Give it a go - Can't hurt.

[Ta22boy]

hey mate yeah well that has already been done, ecu tested fine....so not that unfortunately i wish it was that easy...lol

[Ta22boy]

but i really think it might be a electrical drama somewhere as i have been told there are bad connections in the car, most have been fixed now but i have a auto elec coming over on sat morning to check it further...but until then i just want to eliminate everything else...so im open to any suggestions?

Cheers
Scott

[Hulk]

Fair enuf. Let us know how you go with the Auto leccy.

[Ta22boy]

will do mate, thanks hulk

So can anyone tell me about these pressure switches? please someone...anyone!!

Cheers
Scott

[Ta22boy]

hey well the leccy came around and tested a few things and come up with a faulty AFM, so i am hopefully having it bench tested tommorow and see how i go, its either that or the wiring he thinks.
But he also installs adaptronic's for a really good price and im thinking it might be a good way to go, so has anyone been using these ECU's on 3tgte's? If so what do you do about mounting a crank trigger disc, and how do you re-tain your twin spark setup?

Cheers
Scott

[Ta22boy]

Alrighty i seem to be getting no help here,
Can someone please tell me how to tell which pressure switch is what? all i need to know is why i am losing injection pulse after i disconnect all 3 and when i re-connect one the them i have injection pulse again.....as this is giving me the shits, cause i know now its electrical for sure as everything mechanical has been checked and re-checked....

[Hulk]

the pressure switches shouldn't have that much effect on the injectors. It might pay to check that the vacuum lines are connected to the right places. I still think it's your ecu.

[Ta22boy]

dude, ok i really appreciate your help, but its not the ECU, it has been bench tested by automotive service solutions and was fine....
I dont know how many other ways i can say it, when i disconnect all three pressure switches i lose injection pulse, Now i think that shouldnt be the case....but thats why i am asking because thats exactly whats happening....So i need to know which pressure switch does what so i can go back through the wiring and try to find the F*%K up?

Now does anyone actually know which one is what? cmon wheres simon when you need him

Also hulk just for my own piece of mind, where do the vacuum lines go, from each pressure switch? i will check this, but it still doesnt explain losing injection pulse....

Cheers
Scott

[3jcelica]

when i disconnect all three pressure switches i lose injection pulse, Now i think that shouldnt be the case....but thats why i am asking because thats exactly whats happening....So i need to know which pressure switch does what so i can go back through the wiring

When you disconnect you pressure switches you will not get an injection pulse as you have found. This is normal. This is due to essentially removing the grounding from the boost cut switch.

I forget the pressure switches, but you have a boost cut switch(fuel cut on boost), and a fuel enrichment switch.

It is a good idea to remove the boost cut switch(no a good idea to cut fuel on high boost) and then ground the appopriate wire that goes back to the ECU. If the fuel enrichment switch is working ok then leave it alone, some people ground it but it can result in a richer mixture at lower boost.

I don't think the pressure switches are your problem but it doesn hurt to simply gound all the pressure switch signals from the ECU

Roger

[Ta22boy]

cheers 3j celica....i just wanted to clear that up....now onto the next thing....lol

what i thought might be happening is somehow the fuel enrichment switch might be fucked and causing it to constantly read boost and up the fuel even at idle, causing it to flood so badly it has a miss....but anyways, ill ground it and go onto the wiring again....

GOD DAMN I HATE WIRING...

Cheers
Scott

[3t-RA40]

I ran my 3t for years on standard boost and turbo, no incooler and then around 13psi with different turbo and intercooler. The whole time without any of these pressure switches. When i got computer and cut harness it had none of these switches and the guy who leghthened the harness just allowed for the switches not to be there. Why don't you just get rid of all the switches and that will eliminate that as a problem.
Cheers,
Neil.

[Ta22boy]

because as said previously when i disconnect all three i lose injection pulse, because mine are hooked up, yours were never wired in it so you didnt need them for injection pulse, but i will just ground out the switches and go from there....thanks guys

Cheers
Scott