thats why i'm trying to find the conditions that the secondaries must have in order to fire.

i suppose i could tap the injector wires and put a 12v light on there and run it into the cabin or something, then i could watch when (if) it comes on

 

or use a multimeter. the injectors like most other things on the car i believe are activated by the closing of the ground circuit. the positive or hot side should always be on. so even with the car idling there should be positive charge going to the injector clip. just keep the clip plugged onto the injector and peel like 2mm of insulation from the positive wire. wrap a wire around the bare opening and connect it to the positive side of a lightbulb and ground the bulb to the chassis. if the car's running and whatever the light should come on since there should still be a positive conection. if the light comes on then you can conclude its the negative wire on the clipthat's either not making a connection all the way to the ECU or the ECUitself isnt completing the neccessary ground circuit for the injector. if you had a multimeter you could obvioulsy use that instead in the same way and test for voltage. all you need is a wiring diagram to find which pin at the ECU to test you would just unplug the injector clip and unplug the harness clip at the ecu containing the pin for that wire. then just connect the injector clip ground to the positive battery terminal and test the pin at the ecu harness for continuity by placing the positive lead on the multimeter to the pin and the negative lead to the chassis. if al the wires test for continuity then you have an ecu problem.

wow i rambled but i hope you can make sense of that mess lol

 

yeah we covered all that in the above posts, but thanks for the detailed explanation i guess.

 

lol do you need a wiring diagram?

 

UPDATE:

ok i checked continuity between the ECU and the secondary injectors. all of them checked out OK...

problem persists.


i had the ignition turned ON when i was doing the testing and had the secondaries unplugged. i guess the ECU saw this, and when i started the car, upon stabbing the throttle, it doesnt rev up at ALL. i'm guessing the ECU was still thinking the secondaries were unplugged. after resetting the ECU the car revs up, but stumles under load and still above 0psi it hits a wall...

this leads me to believe the problem is not with the secondaries.
what else could it be?

 

Probably its time for a new fuel pump. Get a fuel pressure gauge and monitor the pressure under load...

 

i set a code with mine that gave the exact symptom you're describing. i think thats why you keep getting the same responses.

heres some thoughts....

1. the ecu is on the ground side, are the secondaries getting 12v power? best way to check is on the harness by the ecu, it should have battery power with the key on.

2. does the check engine light work? sometimes if the ecu gets borked, it doesnt work right.

3. what did you have apart? if it worked before you touched it, then something you touched isnt happy. go thru and recheck.

4. if it just drops dead exactly @0psi it really sounds like a limp home, if the secondaries done come on, it just gradually leans out....

 

interesting.

something worth mentioning: after i got done with the oil injector replacement and got the fuel rails and UIM back on and everything, i started the car and had NO CEL. before, i had a knock sensor code, now i have no codes, and when i do the CEL check i get nothing...

i really agree with you that it seems like limp home mode, but i thought that required a CEL... i'm really confused now

 

Just for the heck of it, pull something that will throw a code and verify that the ECU is still storing/throwing them.

If that works, I would suggest you recheck your steps (i.e. undo everything you did and redo it).

 

ok good idea, i'll go pull the OMP real quick and report back

 

Unplugged the OMP got a check engine light and the standard limp mode, where it would not rev up at all under load. Then I plugged it back in and the check engine light went away and it still revs up and stumblles as before.

 

Well, that's good and bad.

So, that should eliminate anything which would toss a CEL. Have you inspected your ignition system? Make sure that you have the coils, wires, ground wires and ignition harness all connected properly and securely?

 

knock sensor might come back, it might need some time. although it might point to a harness issue too. original harness? 100k? had a motor? seems like the harness is good until you move it, then depening on crispiness its bad....

 

it had a reman installed in 2003 (says the badge on the front cover), and i'm guessing its the original harness...

also, upon driving the car home today i realized that the wall happens at 1psi... if i stay in it for a second (literally 1 second) i can hear the turbos trying to keep boosting, almost like i'm sitting on anti-lag... i'm now thinking its an ignition problem, but i'm trying to figure out how in the hell an ignition problem could cause this.

 

Now that you mention ignition - I had a very similar experience with a fried plug wire (I don't remember which one). It felt like the engine just stopped pulling (this was before I had a boost gauge, so I can't tell you the boost level it happened at), but because of the rotary's characteristics, it did not feel at all like a miss. At light throttle it ran fine, but fell on its face at more than ~1/4 throttle.

Replacing the plug wires fixed it completely!

Dave

 

i got your PM daveW


interesting... i guess it wouldnt hurt to replace all 4 plugs and wires :/

 

I would keep tracking down the injector issue. I had IDENTICAL issues with mine and one of my newly cleaned secondary injectors was bad. It's too coincidental that your failure is exactly at 1psi every time. You weren't near the ignition components and what are the odds that a plug, wire, ignitor, coil etc, happened to fail at exactly the moment that you were doing your work on the passenger side of the engine. Btw, my secondary injector failure didn't setup a CEL either. Try grounding the secondaries at the ecu (rather than directly) and see if you hear clicks. I know you checked continuity but it's worth a shot.

 

If that happens to be the case, gimme a call. I have an OEM FD pump and a walbro FD pump. I'll almost give the OEM one away

 

just checking up to see if you made any progress?

 

well the harnesses are usually fine until its moved....

1psi really sounds like an ecu problem, odd

 

i have the UIM off right now checking stuff out.


i'm trying to figure out which pin at the ECU is the positive 12v for the injectors. i checked the - to the injectors (pins 4X and 4Z at the ecu) and got continuity from the injector plugs back to the ECU. now i need to do the + side, but i'm somewhat confused about it. all four injectors just get 12v from the main relay, right? so as long as i get continuity between the main relay and the injectors its all good. then i could rule out the injectors/wiring as the problem...

here's the diagram fwiw:

 

edit

 

yes if you get continuity from the relay to the secondaries then the positive pwoer to the relay as well as the relay are rules out because any problems with either would keep the primaries from working too. the ecu could still be an issure but i'd tkae that into the last consideration. if u get positive power from the relay to the injectors (which will happen anytime the motor is running or the car is on at all, not sure when the relay get's its power). I'd go and check the same from the fuel pump relay. check to see if the output of the fuel pump relay increases from 9v to 12v when you try and get it over the 0-psi point. if theres no switch then you're relay just isnt allowing the fuel pump to pump enough fuel for the secondaries to do much of anything. sure the map sensor is plugged in lol? i'm sure you've heard it but it does have the same symptoms mostly.

 

yeah the map sensor is plugged in. haha

and yeah, the fuel pressure (and voltage at the pump) is the next thing we're going to check.

 

I had the same problem..kinda, I disconnected my battery and reset my ecu, and everythting is running fine now. I would hit second gear and it would just want to shut down.