adamrx7

Well to start off I was just crueising down the highway and all of a sudden my car starts to puck bad and backfire. After this it wont go if I toutch the gas. I park the car and go inside to let it cool. ow it wont start, just cranks. I start to look at my wires under the intake manifold. (most have 330ohm resisters in them) I move the harness and I see sparks!!! It seams one of the resisters came out enough to ground its-self. So i go to pull codes and I see.

LSSS
LS
LSS
LSSSSSSSS
LLL
LLL
SS
LLLSSSS
LLLSSSSSSSS
LLLSSSSSSSSS
LLLLS
LLLLSSSSS

Thats when I stoped. Did I mess up the ECU???

My mods are "Full"non-seq, K2RD block off plates,330ohm resisters in selinoids, and other non-important to this descusions parts.

Thanks

Mike Baker

Not sure if you killed the ECU but most codes are "remembered". I would suggest clearing them, off the top off my head I think you disconnect the negative battery terminal, hold the brake pedal for 20 seconds, put the cable back on and start with the codes cleared.

Now, onto the shorting. Once you fix the resistor, check the EGI main relay and 30A EGI fuse. The simplest way to check these would be turn ignition switch on and pull then reinsert the relay, you shoud hear (and feel) it click. If not one of these is most likely cooked. If these are good to go, then it is a deeper issue...I am in the same spot and most likely will be needing another ECU.

adamrx7

I went to replace the resisters and reset the ECU but drive 30 minutes away to my car and relized I had left my keys at home. So we'll try it tomarrow

adamrx7

OK I switched out the resisters and reset the ECU. Now im getting error codes.

30- Split Air Bypass Solenoid/open or short circuit
33-Port Air Bypass Solenoid/open or short circuit
34-Idle Speed Control Solenoid/open or short circuit
37-Metering Oil Pump/low battery voltage
39-Releif 2 Solenoid/open or short circuit
42-Turbo Precontrol Solenoid/open or short circuit
43-Wastegate control Solenoid/open or short circuit

I'm not using most of thoes...

adamrx7

anyone

wonder1and

Check the voltage on the OMP if you can to see if its just being retarded.
-Ryker

jwhite94RX7

Those all share a common power source from the main relay through connector X-05, so it could be just one problem.

Sparks were probably the hot side of the resistor being grounded (grounding the battery voltage). This could have blown a fuse. That would be good. Grounding the ECU side of a resistor probably wouldn't have made sparks or hurt the ECU. Measure the voltage on the hot side of your resistors to ensure that there's voltage there.

The bad news is that the ECU pulls that voltage to ground when it thinks it's activating each solenoid. If you somehow bypassed the resistors (i.e., connected power to the ECU pins without the resistor) it could easily burn up the transistor in the ECU that's trying to supply ground to the solenoid (now resistor). Don't swap ECUs until you're sure that your resistor circuitry has been restored correctly.

Measure the resistance of the resistors to ensue that they are still 330 ohms. With the ignition off, measure the resistance to ground of the ECU side of the resistors. They should not be grounded.

I'm guessing here a little because I don't know the exact circuitry inside the ECU, but what I've said is a reasonable extrapolation based on the external circuitry.

Good luck!

adamrx7

thanks a million, i'm going to check that out now.

adamrx7

OK well I checked everything. The main EGI relay is working properly. It's sending power to everything. All my resister's are new and working good(the old ones were fine too).

Now for the weird stuff. the orange,gray and white plug do not have power on the ECU side. Does this mean they are grounding them-self out at the ECU? I get power to the black and white wire wich comes from the EGI relay but no power on the other side of the good (new) resister's. or near X-05 connector near the ECU.

jwhite94RX7

That sounds good. By "power" I'll assume that you mean "voltage". You should have the ground (usually black) side of your voltmeter connected to battery negative (or equivalent) and be probing the b/w wire with the positive (usually red) side of your voltmeter. You should see battery voltage (+12 or higher).

I can't relate to those plug colors. I'm working from the '93 electrical schematic which gives some plug colors but none of the colors you mentioned match the solenoids you listed previously.

Again assuming you're measuring voltage referenced to ground with the ignition on, you should see:

Port air bypass (blue wire) V+ (battery voltage)
Idle speed control (blue/green wire) 8-11 volts
Relief 2 (green/orange wire) V+
Turbo precontrol (blue/yellow wire) V+
Wastegate control (blue/white wire) V+

The Split air bypass terminal must be measured with the engine idling (not just ignition on):

Split air bypass (black/red wire) V+

Or they could be grounded somewhere between the resistors and the ECU, but it's pretty unlikely for more than one of them to be doing that since they're separate wires.

I think you're telling me you don't see battery voltage (V+) or similar on the wires I listed above. That's bad news.

That part of your reply confuses me. I think the b/w wire runs through the X-05 connector on its way from the EGI relay to the common (non ECU) side of the solenoids (now resistors). How can you have voltage on the b/w wire as it comes from the EGI relay, AND have voltage on the b/w wire where it connects to the resistors, but NOT on the b/w as it goes through X-05? My confusion is that the individual wires from the resistors to the ECU don't go through X-05.

If I ignore that last reference to X-05, and if you're measuring the voltage on the ECU side of the resistors correctly, and you're not seeing V+ (as described above), it may be time to swap ECUs with someone.



When you do the swap, pull the old ECU, turn the ignition on, and measure the voltage on the corresponding wires at ECU connector. You should see the voltage there, indicating that when the ECU is connected, it's pulling the voltage to ground (even though it shouldn't). If the voltage isn't there, that's good news because it means it isn't the ECU that's pulling the voltage down. Unfortunately, that doesn't sound likely at this point.

adamrx7

Thanks Jwhite, I have located a local ECU and will pick it up tonight. I'll let you know what happens.

As for the last connent about the X-05 connector, I'm getting voltage to the b/w wire but not poer to the other wires that have no power (the colored connector I mentioned before) So I was basicly conferming that they still had no power like after the resister, so desreguard that comment, Thanks again.

adamrx7

Well I put a new ECU in and nothing . I'm pulling 11 codes!!
5-Knock sensor
11-Air intake temp
12-Throttle Sensor (full)
18-Throttle Sensor (narrow)
30-Split Air Bypass
33-Port Air Bypass
34-Idel Speed Control
38-AWS
39-Relief 2
42-Turbo Precontrol
43-Wastegate

All these connections look good and the wires are ok...Most of them have a new resister in them. Should my next step be to pull the entire wiring harness out and check each wire indivisually?

adamrx7

I pulled my wiring harnes today(that was fun), I found a coroded connection and fixed it. It was on the main black and white power wire. Everything else was good. I pulled out all the unused wires and wraped them up so it cleaned the whole harness up alot.
I did fix error code 5 (knock) I didnt have it pluged in(late night flashlight mistake) and the coroded connection fixed my code 11 (Air intake temp) and the metering pump code. And my code 12/18 were fixed by pushing the TPS connector all the way in(again it was late).

So after two ECU's and the entire harness pulled and inspected,Im still getting the same codes...

30-Split Air Bypass <--I have resister in it's place
33-Port Air Bypass<--I have resister in it's place
34-Idel Speed Control<--K2rd block off plate
38-AWS <--I have K2rd block off plate
39-Relief 2<--I have resister in it's place
42-Turbo Precontrol<--I have resister in it's place
43-Wastegate <-- I have resister in it's place

All my 330ohm half watt resisters are testing good. And the car ran fine with the K2rd block off plates with out throwing thoes codes. The car will not start just cranks and cranks. I'm also concluding both ECU's are good.

adamrx7

Again I pulled the wiring harness and checked each wire at the ECU pin outs. Everyone is good all eight resisters are good and reading 330ohm's all other wires have continuity all the way from the ECU pin-outs to their plug. Both ECU's are sending out the same error codes. Both my EGI and Circuit relays are working, and all fuses are good. Still same codes cpme up.

is wrong!!!!!!!!!!!!!!!!!!!!

adamrx7

Is there any perticular fuse that would do this?

lane_change

iTrader: (20)

This is beyond me....but when you went "Full Non-Seq" did you remove the rats nest? If so, there are 34 B/W wires that have power and they should all be tied together...that is one thing I can think of, especially when you say that the B/W wire has voltage, so it could be that same wire. And if it is grounding against another wire in the rats nest bundle, it could be grounding itself out somewhere along the way. This is just an idea about it all. I have never experienced anything like that with my car or my friends' cars.

adamrx7

Thanks Scott, I had the the entire harness apart and its OK. But then again I can pull it in a half an hour. So I can check it again. But I'm thinking it's some other problem.

adamrx7

Would a Power FC fix this, sense I hear you can turn off thoes selinoids?

I'm going to do a compression check and see if I have spark if it ever stops raining.

books

iTrader: (8)

been reading your thread for a couple of days now..just noticed you're in St. Louis also..having some problems of my own trying to get a reman to run right....I have a PFC and installed it in this car to try and compare logs from my other car...anyway..I don't BELIEVE you can turn off the solenoids with the PFC..it merely reports the voltages or switch positions of the sensors and solenoids...there are function that you can enable or disable.. one of those is the O2 feedback control..don't know if that would help you

Dave

jwhite94RX7

Wow All I can think of now is the pins themselves in the connectors that go to the ECU. Are any of them further back inside the connector than the others (so that they might not be connecting to the ECU pins)?

Double check: Is the ground wire to the ECU (4D) good (zero resistance to battery negative)? Is the ECU case ground good?

Maybe it's all a wild goose chase because of some other problem. How about ignoring the codes and just attack it from the "it won't start" perstpective - checking for all the necessary resources (fuel, air, spark). Are the crank angle sensors good?

Grasping at straws now

adamrx7

ECU pins are good
Grounds are good and ECU is grounded

I checked compression and it's PERFECT
I checked fuel and it's flowing

I have NO spark but I think the ECU is doing that, because It ran after it started messing up for about 4 miles in "limp" mode.





I was told by a mechanic that both ECU's must be bad, I doubt it but who knows.

jwhite94RX7

Is the ECU seeing the start signal from the ignition switch through the clutch switch (terminal 1C on the ECU)? If the starter is operating, the clutch switch should be good, but the ECU must also see the start signal. It should show voltage while cranking.

jwhite94RX7

If BOTH ECUs are doing that, there must be a reason for it. I don't think any of the listed codes should cause the ECU to not generate spark.

Water thermosensor?
Intake air thermosensor?
Fuel thermosensor?

Still tryin' to help.

Therx7ist

I dont know if it's the same thing but my car did the same thing when my 02 sensor wire melted and grounded out on my headers. I'm still having problems with my 88 ECU but I'm almost certain its a bad ecu ground. hailers has suggested soldering in another ground for the ECU, maybe you should give it a shot. ....What else could affect so many systems??

SPOautos

Are all those wires in the same harness? Are there any other wires in that harness that are NOT pulling codes? Does that harness have a ground that came loose or isnt grounded properly?

Could it be that all the solenoids were killed? I know you have resistors but I think you'd still pull codes if the actuall solenoid got fried.

STEPHEN