Pozi

Thanks for the reply. I do not have the complete FSM manual for the 98 engine but I have the engine control diagram.

The #1 plug is firing and yes the #4 plug is also firing.

Also the #1 and #4 plugs fire continuously and not just once.

Willcipher

Pozi,

What year and model is your ECU? A 98 4Runner ECU will be 89661-3D3XX and a 98 Taco ECU will be 89661-04XXX (X's vary on Fed or Cal, MTM or AT, 1 ton, LEV, etc). You need to have the correct year factory EWD for the exact year ECU you're using. Without this, you'll never resolve your trouble. Post up your ECU number and I'll cross reference it to the correct year. Then you can confirm that the EWD you're using is the one you need. Toyota used 3 different plug styles between 95.5 and 02 on the 5VZ ECU's and changed the pinouts within the same plug styles from year to year on some occasions :pat: From what I've read, it looks like you're close to ironing this out. As stated before, you don't need the O2 sensors to run the engine. I suspect that the wiring harness and ECU are not pinned out properly. In the 98 models, the M/T ECU shared the larger style A/T plugs but the pin configurations varied between A/T and M/T. I doubt the ORS harness is the trouble; I've never seen one but it shouldn't be associated with the plugs going from ECU to ignitor / coil packs / injectors. Correct me if I'm wrong, but Mike's harness only attaches the ECU to the body, right?

Will

MTL_4runner

Well put, this is what I was trying to get at above.

It isn't that I think the ORS harness is wired wrong, just that there are many ECU's with similar connectors and different pinouts year to year. My thought would be that ORS might have had people with similar engine symptoms (who might have had a harness/ECU mismatch) that they helped them work through while verifying the harness and ECU were compatible.

Gadget

I think it has been mentioned before.

The ECU wire color codes and pinouts change every year or two.

I have no idea what is included in this convertion kit, but if it includes a wire harness, then you must find out eactly what truck, tranny, and 4x4 or 2x4 and of course year that was built foir. Then get that exact ECU and engine wire harness for that exact year and truck and everything should then plug in correctly and the proper signals will get to and from the ECU as they should. Just one function being one pin off will screw you.

Gadget

mt_goat

One of the first questions ORS asked me was the vin# for my truck and the vin# for the donor truck so they could custom build it for the exact year ECU, engine, tranny, etc... Plus they ask for the years of both trucks, engines, trannys, etc... But if you gave them the wrong info or the salvage yard gave you the wrong info then it could be wired wrong.

MTL_4runner

Yep, it's the most likely scenario IMHO.
Gadget is spot on as well, all you need is one pinout wrong or one pair reversed and who knows how the ECU would respond.

Pozi

Mike from ORS is looking into a possible solution. I will let you know what he says. Please stand by. =)

Pozi

Ok.

Mike verified that the ECU and the wiring harness both match. And the ECU I obtained from a 98 Tacoma should work also with my engine.

Good news? Maybe but it still does not solve my problem. He mentioned that he has seen many salvage yard ECU's fail (something contrary to what was said in the other thread). But to have two consectutive ECUs fail????

Other then this he suggested that I hook up a diagnostics scanner to see if there is a failure code. Something I do not own.....What is a good unit that I can purchase at a reasonable price?

Another suggestion was to check the ground of the ECU (something also suggested in the other thread) by the intake plenum (left side by the diagnostics connector). Which is good; however I was wondering if there is any other grounding points for the ECU which must take place? Does the ECU body itself require a ground ?

Thanks,

mt_goat

http://www.urdusa.com/index.php?cPath=76_71

midiwall

We're talking OBD II here, right? Not something to tie into the diagnostics connector near the plenum?

You can get a cheap one (only displays a trouble code and lets you clear it) from Habor Freight for about $35. or, many autoparts stores will let you borrow one overnight. There are many "good" ones around $100-150. There are also plenty of options if you own a laptop or a Palm handheld.

This is a whole 'nother thread. For now, I'd suggest seeing if you can borrow one from a store.


The case on the ECU is tied to that ground lead, but in the stock location the case is also bolted to the body up behind the glove box. If the body isn't electrically connected to the chassis, then the box ground on the ECU is one point where the engine becomes tied to the body.


fwiw, Gadget's selling above the manufacturer's actual price:

http://www.obddiagnostics.com/order.html

Pozi

Ok the number on my 4Runner ECU is 89661-3D360

and the Taco ECU number is 89661-04415

However I do not have a part number on the engine wiring harness. Is there someway to tell which engine I have by comparing on of the connectors somewhere? The original tag that came attached to the harness had fallen off before I got the enigne.

Pozi

Like this one?
http://www.harborfreight.com/cpi/cta...emnumber=46030

midiwall

Yeup, that'll read a code, but it looks like the price went up - way up. That's the one that won't clear codes (though can do it just buy pulling the EFI fuse) and I thought it used to be like $35.

If you're willing to drop $50, then I might suggest that you spend another $50 and get the OBDDiagnostics box (link above), though you need a laptop or a PC to hook it to.

Pozi

Not being able to start the engine what could possibly be wrong though. I may be just missing something but I have always thought a scan tool was used when the vehicle is started.

midiwall

Ummm, I'll agree with you that it's certainly more useful in a non-catastrpohic failure situtation, but there are some things it can tell you.

Check this failure code list for the possibilities: https://www.yotatech.com/forums/f128/obdii-trouble-codes-76363/

(P0100, P0110, P0120, P0200-P0206...)


Again, your best bet may be to see if you can borrow one from an autoparts store. It'll save you $50 and the time spent waiting for it to show up only to find out that the ECU hasn't thrown any codes at all.

MTL_4runner

.....plus you should be able to access realtime data from a majority of the sensors which might indicate where the problem lies.

Sorry to hear about Mike's comment because I think that just blaming it on the ECU is a bit of a cop out on his part. I think the chance of 2 ECU's being bad is very, very slim (but still plausible).

midiwall

Good Point! But Pozi, know that you can't do this with the $50 HF reader. You'll need something "more".

Pozi

Thanks for that. I will check with the local autopart stores and see if I can borrow one. I will avoid the HF tool also.

Now my laptop could be put to use for something other then school work.

midiwall

Cool.


Oh you BETCHA'! Once you get the engine running, you can start looking at logging some of the engine data for performance and general health graphing.

When you get ready to do that, let us know and we'll talk about the OBD II options. The OBDDiagnostics box _will_ graph, but it's proprietary software.

There's a slew of readers that are using a common protocol which is being used by an additional slew of applications to do a slew of cool things. To start the drool, check in here:

http://obd2allinone.com/sc/details.asp?item=obd2ser
The buzzword is "ELM 5". That's the protocol that's become "standard" and "common" for doing OBD II work. It's a single chip that's very easy to talk to.

http://obd2allinone.com/sc/pages.asp?pageid=60
That's a VERY small sampling of software that will talk to that box.

I have 3 readers... the OBDDiagnostics box; the OBD2AllInOne (above) and the Auterra (for a Palm or PC). They each have their place....

midiwall

btw... did we ever ask where you were in the world? I thought we did, but I can't find the message. Could you update your profile to at leats give us a general location? Maybe one of us could pop over and help...