Where is the diagnostics plug-in on a 90' Samurai (TBI 1.6L 8/v if it matters).

If it plugs into the ECM.. is there a special way to do it?

Thanks!

A 90 Samurai with a 1.6, 8v TBI?

The Samurais were all 1.3, so that didn't come out of the factory that way - so the real question is - what did the engine come out of, and where did the person who did the swap put it?

OK - one of your other posts says a 90 Samurai, with a 92 1.6 engine and the EFI from the 1.3.

First - there may not be a "diagnostic" plug for a computer, and if there is, your new problem is finding a computer that can talk to the ECU, it's not OBDII, so most diagnostic scanners won't pull the codes - you may be stuck with the paper clip & counting the flashes of the check engine light.

Having looked at a couple of the other threads, I can't help but wonder if you're "chasing your tail" - the 1.3 ECU was not designed to run the 1.6 engine, and whilst it may do it, what are the chances of you getting all the quirks out of it?

Hmm...well he doesn't really know...so I guess that it does not plug into the ECM? If it doesn't have a plug in is it easy to add or tie into where it should be?

You posted whilst I was editing to my post - sorry about that.

I found a diagram for the TBI 1.3 over at Ack's FAQ and that only shows a 4 wire monitor connector - which I believe is the one under the hood where you put the paper clip to get the CEL to flash.

I doubt that there is a diagnostic port - however - if there is one, it should be under the driver's side dash, but it may be a 12 pin connector rather than a 16 pin one, and as I indicated earlier a 90 Suzuki will not be OBDII compliant.

That's crummy! My problem is the engine runs when the MAP is unplugged to the motor...when the map is going to motor the engine it backfires, misses, and eventually dies. I replaced the O2 and that wasn't the fix...Im going to test the map to the specs according to the books and go from there...if the map is to spec then I don't know what to do!?!

I really appreciate you looking into that for me! My cousin has a pro diagnostics computer and he was going to bring it over tomorrow if he had a place to plug it in. He says it will read odb1 and will give him everything he needs to further diagnose my issue

Found it!

I like where yours ended up being located. Nice and easy to get to. Out in the open so that you can reach in and go to work.

Found it!

That's the "monitor" connector I was referring to - the one you jumper to get the CEL to flash - it has a couple of other uses, another jumper freezes the ignition advance so you can set the timing, and I think there's a way to monitor the O2 sensor duty cycle - but I don't think you can plug a computer into it and get any data.

As far as I know Suzuki used/uses two different connectors for computer connections, a 12 pin connector that is also used by GM for ALDL (please note - Suzuki does not use the ALDL protocol), and the J1962 16 pin connector commonly associated with OBDII, (please note - the presence of the J1962 connector does not mean the vehicle is OBDII compliant)

With regard your cousin's pro diagnostic computer and OBD1 - the big issue is that there is no single OBD1 standard (OBDII is a federally mandated standard), and many manufacturers have differing OBD1 protocols, Suzuki is no different in this regard and their OBD1 protocol is known as SDL or serial data link - there are very few readers available that can communicate with a Suzuki OBD1 ECU.

Take a look at Rhinoman's Suzuki Diagnostic pages - there's not been very much work done on the Samurai ECUs, but, and as I said, I'm not certain if your ECU does have a communication port (not all do), but if it does, this software will most likely be able to communicate with it - please note - the software is a work in progress and most likely does not have a configuration file for your ECU, however, with a bit of work you can create your own file.

well isn't that a bummer!  Of course it is 20yrs old and guess you can't expect 20yr old vehicles to be as electronically advanced as the ones today....

Thanks for your input and help --- i'm going to look into your keywords and see what they mean and how to proceed.

I tested my map sensor and put the results in another thread about my O2 sensor --

At first I was looking to get all the bugs out because I figured it was possible...now I'm just looking for it to run connected to the MAP sensor...heh

The Sammy ECU that I have has a diagnostic port although it seems that on some models it wasn't connected externally. A 90 is very early though so it may not have a serial port. The official Suzki tool covers 1991-on but a photo of the ECUs circuit board would help.