legacycentral bbs

Okay.
So this is the problem, and you can read up on the old threads from Js92tru, cause i bought the car from him, he was having the problems, and i am finally getting around to tinkering.

Basically, when the car is completely cold, start, runs on i think all 4 cylinders, for about a minute, then it begins to slowly cuts off the pulse to the 3rd injector and begins to run like crap.

With a noid light connected to the #3 injector harness, upon a cold start, the light pulses okay, but in about a minute, it slows, then in a couple more minutes, the light stops blinking completely.

shut car off, restart, light blinks once, then nothing.
Let car sit for long time to cool, start, seems okay for the first minute, then slowly dies off.

Listening to the injector with a stethoscope, the other three injectors click rapidly. It is just the #3 injector. The voltage at the injector is 12.2 with engine off.

Why would the injector signal work at first, then stop?
I am about to test the continuity between injector harness and to the ECU.

anythoughts. spark is good, new plugs, plug wires good, voltage good. I have extra injectors, but if the ECU is cutting the signal after a minute....i dont know. Coolant temp sensor is newer. Knock sensor is new. tried a different cam sensor. it has to be something in the ECU, but why would it work briefly?? could it be maybe and O2 sensor problem. why just injector #3??????

Hm. I don't know.

When you checked with the noid light, was the injector hooked up as well?

I know later model ECUs sometimes shut off injector #1 when there's an IAC valve problem. I didn't think any of our ECUs did that though. This is a 92 turbo? Are there any trouble codes?

Out of curiosity, if you swap the #1 and #3 injector connectors, what happens?

yes a 92 turbo
The noid light is connected to the injector connector, but that leaves out the injector.
no codes, but i have reset the ecu, and swapped in another.
but as of now no codes, but the car cannt really be driven in its current state with the cutting, bogging, rough violent shaking.

I swapped out the #3 injector this weekend, but to no help.
Also swapped back in the original ECU this weekend.

If the timing jumped somehow, would it cause this? It starts, but wont run smooth, definitely bogs, cuts out, wont rev past about 3500 evver.

On a cold start, runs smooth, but lack of power, bogs, cuts out. Then after a couple minutes, the engine begins to shake and run rough. The tach needle bounces around abruptly.
O2?

So far, here is the list of things that have been tried out:
different coil
new knock sensor
different pressure solenoid valve
new plugs NGK
different plug wires
different ignitor
swapped camshaft sensor
different injector
did a compression check, all 4 are 165 psi, with a snap-on tester. (checked compression on cold engine though)
temp sensor is newer and looks okay.

I guess I will be checking to see if the timing might have jumped, but would like to know the symptoms before i go this route. The timing belt was replaced around 20,000 miles back, according to the records, but maybe they reused the tensioner.

I want to get this thing running. about to have it flatbedded to the nearest Subaru dealer, that is about 60 miles away. tha will cost around 2.50 a mile, and i doubt the dealer will be able to figure this out either, they will just do what i have already done, as well as prevous owner Jay did. Also, I doubt that the dealer has as much experience on these as me, i am now in Iowa and I doubt the dealer has ever worked on a older gen turbo, they just arent around here, and never were.
anythoughts.anyone

I suppose it's possible that if the timing jumped in exactly the right wrong way you could end up with three cylinders firing and injecting at the wrong time and the fourth one not at all.

You may as well take a look.

What happens when you try to rev past 3500 RPM?

okay, another thought, is there something that will not allow a 5 spd to rev while in neutral, and the car is not moving? most of my testing is done with the car in my garage.
I have taken it out around the block and around the side street a couple times, but the car just has no power, it buks, cant get it going any faster than about 25 or 30, any gear.

with the car running, and in neutral, if you give it any gas, it just seems to cut. if you floor it, then let up, then give it more gas, it will rev to around 3000 rpm, but a few times, feathering the gas pedal, i can get it to about 3500. nothing more.you can hold the gas down, and it just sits there low rpm, no smoke out the tailpipe, no oil burning, maybe rich tho

No, there isn't a different rev limiter when in neutral.

It sounds like you might actually be getting fuel cut when you are hitting atmospheric manifold pressure.

What's the story with the Check Engine light? Is it on? Any codes?

no check engine light. no codes. but the ECU was reset, and it is not really driveable, so it might not be giving a code in the time i am letting it run.

just swapped back in the original ECU that jay sent along with the car. both ecu are identical model. I have 2 other good ecus, in my other cars. Think both ECU good with that came with this car.
O2 sensor?
bad fuel pump? i doubt the fuel pumo is bad, cause the other cylinders seem okay. you were helping Jsttru with this too, i read all the old threads. he gave up. he sent your scan tool cd, and has a connector, and plug for a paraller port. I have a laptop, but have neve tried to this. where do i plug in the connector? then just boot up laptop with car runnning? are the results written to a file? what will this help.

If you think it's the oxygen sensor, just unplug the sensor, reset the ECU, and see how the car runs without the sensor.

I don't see how a bad fuel pump could make one injector not fire.

I guess you should check the timing belt.

Oh, also, try hooking up the noid light directly to the ECU's injector #3 pin. Connect the other terminal of the noid light to any +12v source. Maybe the light will work; if it does, you just have a problem in the wiring.

oh, forgot to mention, i tried to unplug the O2 sensor, let it run. no difference in engine, no CEL.

vrg3 wrote:If you think it's the oxygen sensor, just unplug the sensor, reset the ECU, and see how the car runs without the sensor.

I don't see how a bad fuel pump could make one injector not fire.

I guess you should check the timing belt.

Oh, also, try hooking up the noid light directly to the ECU's injector #3 pin. Connect the other terminal of the noid light to any +12v source. Maybe the light will work; if it does, you just have a problem in the wiring.

okay, i can check the ECU output to the #3 injector, it should be the blue/white wire, i traced the wire from injector to the electrical connector plug by the battery, and it had conitinuity there, so myabe the ECU to the plug has a short. I have to check the FSM manual again, to make sure that i have the correct wire at the ECU.


again, though, why would it get worse after the car has run for a minute or two.?
thanks again for the help and advice.

Well, try removing that contact from the harness and testing directly at the ECU pin with nothing else hooked up to that pin. I want to know if the ECU really isn't trying to drive the injector.

I have no idea why it would get worse a few minutes after startup.

Had some time to spend on this today.
removed battery from car. Unmounted ECU. Removed all ECU connectors, checked the conitinuity for the #3 cylinder wire at the connector ECU side, all the way to the Injector harness. Good continuity. Wiggled connector by battery, no change in continuity.

Then I grabbed another ECU out of my 93 SS. Plugged it all in.
put battery back in.
Determined my battery was not good. Had charged it all morning on a charger, installed, click clcik click.
Either charger is bad, or bad battery. Determine by taking battery to nearest wal mart, the battery is bad. Buy brand new battery, the best one they got.
Install battery. Starts, but just wont run, it idles, but if you touch the gas, it can reve to only about 2500-3000, then sputters, misses. On idle, it is still sputtering, tach needle bounces around some, like it bounces 700-900-700 etc. give it any throttle, 50 % and it cuts out bad. . Now it seems the problem even happens on a cold startup (outside temp near 75 F, as opposed to 35 or so last time i messed around with it)

Changed to another spare injector. no help. Listen to injectors with stethoscope, 1,2,4 sounds like rapid noisier clicking. #3 has a fainter, lighter clicking, like it isnt firing right. it is defiinitely a diifferent sound on #3 injector.

Went back to the original ECu

Swapped out another known good MAF from my 93 SS. No change. swapped back to original MAF.

Checked PCV valve by removing. shake, it is good. it clicks

Just took out the front fans, and removed the Timing belt covers. going to check timing tomorrow. I am new to Subaru timing. I see the cam sprockets have an outer line mark on each front. And then next to the L, there is an arrow inside the sprocket. On the R, there is an arrow on the inside of the sprocket. Both those arrows point same dir. Turn crank, both point arrows point up at the same time. Is this correct???? i will check my FSM manuals tomorrow on how to check timing lineup.

doesnt look like the belt could have jumped, it is in good shape, replaced around 15-20K back by Jay before i got the car.

Any other things to look for. Pretty sure the wiring and ECU is good now. TPS? MAP? Pressure solenoid valve. Turbo? O2 sensor?

I still need to check the ECU injector #3 with a noid light at the ECU pin directly.


WTF? This car needs to run soon. No CEL, but i cant exatly drive the car around, it bogs, cuts so bad it cant really be driven.

Also, with the car runnning, i can pull plug wires off at coil, one by one, and every time i pull i wire off, it changes engine idle, except witht the #3. Yes the coil is good, there is spark on all 4 at the coil. Plug wires good too. also new plugs. NGK BKR6E11

Clogged CAT? the #3 cyliner is closest to the exhaust outlet, so maybe it would cause wierdness at that cylinder..

And still no code for injector #3?

It seems like it's gotta be the wiring. Maybe you should just cut the injector connector off a couple inches from the injector and run a wire from one side all the way to the ECU's injector #3 pin and run a wire from the other side to a fused +12v source (you could even just put a fuse in the wire and connect it to the alternator terminal with a 1/4" ring terminal).

A clogged cat couldn't cause one injector not to fire.

Did you ever try swapping the #1 and #3 injector connectors to see if it would make injector #1 not fire? It's a quick 30-second check.

when i toggle the injector harness from 3 to 1 and vice versa, it seems to follow to the cylinder the harness is moved to. With the injector connectors switched, If I pull the 3 plug wire at the coil, , it seems to make the engine miss. And when i pull #1 plug wire at coil, no change.
When the injector harness back to normal, i pull #3plug wre, no change, but pull #1 plug wire, and miss.

So, I will attempt to determine if: The polarity at that injector harness are reversed. this is doubtful they are reveresed. I will compare the readings to my other cars.

If they are not reversed, i will cut the 12v wire and rerun that directly to the battery, with fuse in line. Then will test.
I know that the wire from ECU to injector has god continuity, so maybe it could just be the 12v wire bad, or shorting.

If that doesnt work, then i will then rerun the other wire direct to ECU pin.

will reply with my updates today is nice out, awesome weather to work on it.

I don't believe our injectors are polarity-sensitive.

Realize that a continuity test doesn't really differentiate between a good wire and a marginal wire...

Good luck with the rewiring.

yeah. i have a couple extra injector connectors i got out of the junkyard. so that should help.

update.
Totally bipassed the original wiring for injector #3, jumped across new wire from ecu pin, to injector, and from battery to injector.

Started car, same.

hooked back up originall way

Swapped out #3 injector with another, I think i need to get a brand new one to swap in. Anyways, the injector i have in there now does click, and it sounds pretty much same as the others sound via stethscope. Engine can rev to around 3700-4000, but it is defiinitely pushing it to get to 4000.

Held it there for a while. idle, rev, idle. I can here a somewhat metalic click sound around the rearby throttle body, iopen up throttle, it revs to about 4000, let off and it clicks, open throttle, let off some clicks.

Here is the biggie.....looked under car, and glowing red orange around downpipe, and back at CAT in mid pipe cneter of car. Bright red hot glowing orange.

So, could this be a siezed turbo? what do i look for.

How old is the catalytic converter? Could it be clogged?


And have you replaced the coolent temp sensor?

there is exhaust pressure out the tailpipe, but i guess it could be restricted. I will try and get more info on this, and a comparison of the pressure it puts out compared to my other SS.
The CAT is the OEM, with 140,000 miles. The car came from Minnesota, so it does have some rust on exhaust, primarily the muffler. I never seen something so bright orange, looked like the embers in a hot hot fire up under the downpipe and at the CAT.

coolant temp is newer.

So even now, disconnecting the #3 plug wire has no effect on the engine's smoothness?

I don't understand how the problem could be the injector if the problem moves to injector #1 when you swap their connectors.

Is it possible the contact in the ECU harness connector for injector #3 is bad?

Oooh... that's interesting about the cat overheating. That normally happens when raw fuel is being sent out the exhaust due to excessive misfires (the fuel essentially burns inside the cat). Well, we already know your engine is misfiring... But if it were because of lack of fuel you'd expect the cat not to mind.

Soooo... maybe this is an ignition problem somehow? I know that doesn't make sense considering much of the other stuff we've seen here, but still... Try swapping plug wires with another cylinder? Do you have another ignition coil you could try?

You should be aware (and it should be obvious) that this isn't good for the catalytic converter.

hmm.
I got the timing belt covers off the left and the right sides and crank pulley is still on as well as center cover........
The factory white lines on the T-belt are BOTH lined up 12oclock with the back cover marks, BUT, the cam sprocket marks are not ligned up with the T-belt white marks.
the cam tick marks are both off to about a 9oclock position on both, when the white belt mark is at 12 oclock. .

I am removing the crank pulley tomorrow, to check the crankshaft mark, but I am assuming that the camshaft marks should be ligned up on the marks of the belt, and they are not.

If the timing is off, and the car has been run this way, any damage?

Also, if the timing is off, then I am getting a new tensioner before i got any further. The belt is newer.

TIMING BELT ON WRONG MARKS. YEP plus maybe some of the other stuff, maybe the old injector was stuck. But yep, today I redid the Timing belt, and it runs great. This is the first time for this car for a long while.

Just changed oil in it, and am going out to drive it some tonight. YEAH.
Thanks to those who have helped me with this......thanks for the time spent.

YaaaaaaaaaaaaY!