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Full Version: weird wiring and fuel delivery problem
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Let me first layout what I have. It's a 1988 1/2 Samurai that has been converted to fuel injection with a 1989 tracker system. I drove it home when I bought it (@50 miles) and it was not driven again except for starting it and moving around in the yard so I could mow around it. I've spent the last 18 months or so completely restoring it from the frame up. Last week I finally finished connecting the wiring back and filling it with fluids to try to get it started. When I turned the key on, the motor turned over good but there was no fuel to the TB. Poured fuel into the TB and the engine will start and run until the fuel burns off. Noticed that the fuel pump didn't run until the key went from "run" back to "accessory". It would not run in "run" or "start". Sent my ECM to Digitalguy in MN, and got it back today. While I waited for him to get it done, I removed my dash and rechecked all the wires. I took the harness out and chased/checked all the connectors against the wiring schematic, tagged them, and reattached it to the back of the dash just like it was from the factory. Put the ECM back in, double checked my connections, hooked up the battery, turned the key...same problem. But, I've found out that not only does the pump run when the key is returned from "run" to accessory, it runs when the ignition is turned off. It even runs when I unplug the ignition from the harness.

So to recap:
Ignition off - no pump
Ign. accessory- no pump
Ign. run- no pump
Ign. start- no pump
Ign back to run- no pump
Ign. back to accessory- pump runs
Ign. off- pump runs
Remove fuse -pump runs
Disconnect ignition - pump runs
Unplug fuel relay - no pump

Unplug harness from ECM- main relay pulls in just like it's supposed to and doesn't go off as long as the key is in run or start position. But as soon as the key is in accessory, main relay opens.

Started checking voltage. So I put the ECM back in. Turned the key to run then off again to get the fuel pump running. Put my meter probes into the main relay connector at the black/white wire and then to ground. As soon as the negative probe was grounded both relays opened (main and fuel). Did the same thing on the fuel pump relay. Put the +probe into the connector at the black/white wire and then touched my - probe to ground and the relays opened. The opposite side of the main relay coil is a black wire that goes straight to ground. The opposite side of the fuel pump relay coil is a pink wire that goes to the ECM. I cut the pink wire and then turned the key to run and the main relay pulled in just like it was supposed to. The fuel pump relay though didn't pull in. I grounded the pink wire that I had previously cut coming off of the fuel pump relay (kept the pink wire from the ECM hanging loose) and it too then started to work exactly like it was supposed to. So it seems the culprit is the pink wire. When I check voltage on the pink wire to ground I get 8.5v with the ignition on. I assume there should be no voltage on the pink wire since it is the ground leg for the fuel pump relay, but I don't know what goes on after it goes into the ECM.

While I had the pink wire grounded and the fuel pump running, I tried to start the engine but the injector wasn't spraying any fuel.There are no sensors that detect fuel pressure so I thought the injector would fire regardless of fuel present. Using a 12v bulb and socket from an old turn signal, I rigged up a noid light and wired it to the red and yellow wires that connect to the injector, but I didn't get any light when I cranked the engine over. So it looks to me like I still have a ECM problem. Any suggestions? Open to any ideas.
its no 89 ecu nor is it 89 harness
there is but one control relay on 89/90s
so my post is just a waste of my time...
recap
what ecu, pn
what harness, its no 89 for sure.
so what is it, if we knew that we can test all pins, or just 6pins on the relay and tell why no PUMP POWER

show photos of relays, or relays, the 89 has only one, so why not tell us all why your car has 91+ harness?
and please...... stop hot wiring ECUs (this is no 60s ford, it's got electronics)
unless $400 + is cheap pocket change. for a fully rebuilt ECU,
illegal hot-wiring electronics is rule one, dont....
i can teach you to run an ecu on the bench but that is bench testing hot. and is not hotwiring
for sure never hot wire any ECU output pin ,or boom.
and that means same with hot wiring fuel pump relay sockets. boom , the relay driver smokes, blown to H3LL
I appreciate you getting back to me. I feel really bad. You spent a lot of effort trying to help. I found my problem, A bad ground connection on the (2) black/blue wires coming off of the ECM. Engine fired right up.
im still curious, its not a 89 G16 ECU nor is it 89 tracker harness is it.
and not one 89s has pump relay by itself. so its not a 89 EFI system, is it.
black blue is the ECU main ground,
that tell me the harness ground called,G105 to body is cut.
that would kill any ecu made, zero power to eCu and CEL dead. key on, top clues.

all you need is this if it really is 89s parts ;harness and wired.
1 pdf.

its all there.
http://www.fixkick.com/ECU/89/1990-scan-...lpages.pdf


down to ground names and all. its the GM set and Suzuki set in 1 pdf. only I have this.

hope it stays running for you.. cheers
The engine is a 1.3 8V
ECM#33920-60A31 -There is a paint marking on the ECM that says "89 Tracker M/T" like you would find in a salvage yard. That is why I assumed it was an 89 system.
The wiring harness matches the wiring diagram I found here:

http://www.suzukiclubuk.co.uk/pdfs/90-92...am_USA.jpg

The following are not on my engine:

EGR VSV or EGR (has block off plate)
Throttle opener or Throttle opener VSV ( the throttle opener was on the TBI but when the plunger was completely extended, it didn't reach the throttle assembly nor did it have a vacuum hooked up when I got it)
Igniter ( connector was there but not hooked up. Instead the orange/black wire was cut and tied to the brown/white wire on the distributor)
Resister Coupler
Spark advance is not connected to vacuum.

Like I said, I haven't driven this vehicle but once, so if there's something that's not running optimally, I don't know it yet. I fully expect there to be some issues once I get it on the road. But for now it starts right up and idles smooth.
ah the 1.3L but those here are all CARBS. trackers, no ECU , no TBI. (sound to me like a mix of all parts. 1.3, with1.6L and wrong year harnesses.

The 60a31 is the 89;90/ ecu, used only 2 years, and makes ZERO SPARK the Distributor on that car makes all its own spark, and has VR /IGNITOR and centrifugal advance system.
That is the dash pot, and the ECU loves to flood lacking that device.....
is the TBI top right side , the ISC has 2 wires, but are they with a connector or just 2 wires, the only 2wires, is 89/90
the 89/90 runs a special sized injector and so does the 1.3L in 1991 all this changed, why not post a photo of all that, I can tell you in seconds what you have. with photos.

the 89/90 EFI is totally not same as 91- up. radical different is the word.
the vacuum advance give you lots of torque off the line, lacking that power is limited to higher rpms and long delays.
the problem is what intake is there, G13, G16 and what year.
what TBI, 89. or 91+


no 89 has a stand alone Fuel pump relay, none do , if you have one that is in fact 91 and up, and is in a green socket under ecu, that is not 89 harness.



91+ TBI
here, see that ISC on top and it its connector?
http://www.fixkick.com/engine/8v-Show-bo...ge_15.html
now look at 89s
its very much different, all this is on my find parts page.

the isc has no connect part of its self. the 91+ has on ISC body a connector with 2 pins.
http://www.fixkick.com/sensors/89/89-TB-exploded1.jpg




http://www.fixkick.com/engine/8v/vacuum%...age_6.html
I'll try to post pics

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