bought a SHO, help me make it run

I would call these guys and be done with it:

www.diyautotune.com/

thanks for hanging in there with the story fellas....

I tried swapping ecu's, no dice.

I found all three pin-outs to the ECU that are supposed to lead to ground. They do :(.

sergio wrote: Unplug the coolant level sensor in the overflow bottle and see if it fires up. I know it sounds stupid and I don't remember exactly how, but if it shorts out somehow it's wired into the ignition or injectors. It's been a half life since I fixed on those.

and i tried this too.

Stick with it. Don't let the car beat you.

belteshazzar wrote: at this point i just want to win. due to the circumstances involved it will be more satisfying than normal.

This car will fight you every millimeter of the way......they all do. Keep it up, you have more patience than I.

On a side note, can a bad injector ground out the others?

Power from all of them is spliced off one circuit so if one shorts to ground it will pull down that circuit and either pop a fuse, OR at least you wouldnt see proper voltage on the rest of the injector pigtails.

Try unplugging the engine coolant temp sensor, it's under the throttle body just to the right. 2 wires, round fbarrel connector. The gauge sensor is 1 wire to the left of the TB. Don't confuse the engine coolant sensor with the heater cold lockout switch that's located on the metal heater pipe near the head by the firewall. That just keeps the heater fan from blowing til the coolant is warm.

Does the new motor have any of the old overheated motor sensors on it? If so I would change them.

yamaha wrote: On a side note, can a bad injector ground out the others?

this is where i would start. try unplugging one injector at a time and try starting it. i have seen more dead because of a bad injector grounding out the system and it wont pop a fuse all the time. 280zx's this happens to all the time

yamaha wrote: In reply to Vigo: If it has spark, the ecu knows what rpms are at.

I'm not sure about that.

The SHO was one of the first motors with DIS, and with that, it used an external box that read the crank signal, which it used to time the spark, and it passed that signal to the EEC IV to start injection.

On those era of cars, it would either use one big injection per cycle or a bunch of small ones- either way, if the EEC didn't see a signal from the EDIS module, it would not inject fuel.

On the other hand, the EDIS module will spark at 10 deg BTDC if it does not see a signal from the EEC, so if the EEC isn't reacting, it will still spark.

I wish I kept some of my old documents, but all I have easy to find is a EDIS module form '89, and I'm pretty sure that's not the one on the '93. But there is a pin from the EDIS to the EEC giving it a good PIP signal (and I think that's what it's called, too). Going the other direction, there was an easy plug to pull from the EEC to the EDIS which forces it to run at 10deg.

Anyway, if you can find the PIP signal from the EDIS to the EEC, see if that's good. If the EEC is good, perhaps it's not getting a good PIP from the EDIS module.

In reply to alfadriver:

So to add some info- ironically on the interenet- EDIS pin 1 is PIP (out to EEC) pin 3 is SAW (back from EEC).

And this diagram should help- http://www.justanswer.com/uploads/ZZdaryl/2009-07-26_134658_sho3.pdf

It shows that PIP goes back into the EEC on pin 57....

But now I'm back to being confused- and if that diagram is right, Yamaha is right- that diagram shows internal EDIS.

So can you find out if you have a box that controls the spark or it comes directly from the EEC?

In reply to alfadriver:

Man, I keep adding to myself... Ok, so I'm going on that Yamaha is right, and this is internal EDIS, and that the engine knows what the speed is.

With that, check and see if the CID signal is working correctly. On the diagram I linked to, it gives a location to look for it. And it looks like CID goes into the EEC on a dark green wire on pin 24.

IIRC, without that, the engine will not SYNC, and because of that, it will not fire the fuel. This would be one of the early motors that had fully sequential fuel injection, and while there is an error mode where it will try to batch fire, I also recall that a very common error is that it won't do anything.

So check for those signals.

it will fire crank fuelling w/o the mass air flow sensor. and it should try to limp a fuelling with it disconnected.

it's been a while, but I did work on the 3.2l SHO's, as we used them for electronic throttle test beds. It was fun.

In reply to alfadriver:

The 3.0 and 3.2 both have a DIS module that sits on the crossover tube for the intake on the passenger side. If they aren't working properly, they will throw a code and he won't have spark at all.

The only reason I mention fuel injectors is due to the only case on shoforum similar to this, it was remedied by a few sensors(while trying to figure it out), an ecu, and finally a new set of injectors.

In reply to yamaha:

If it has an EDIS module, and is working correctly, but isn't connected to the EEC properly, it will spark at 10deg BTDC.

If I read the thread right, this is already a replacement EEC, and it seems to be shown that the injectors are not firing. So that means that IF there is an EDIS, then it's possible that the PIP signal isn't getting to the EEC, so it has no idea that it even needs to fire the injectors.

That's why I bring it up.

It's been a LONG time since I did any SHO work. I used to have a floppy with the calibration on it. But I threw those away a few moves ago.

Well, its good to know my original guess wasnt completely off-base. I knew there was some situation where an old ford would spark even if the ECM didnt know the engine was turning.

alfadriver wrote: In reply to yamaha: If it has an EDIS module, and is working correctly, but isn't connected to the EEC properly, it will spark at 10deg BTDC. If I read the thread right, this is already a replacement EEC, and it seems to be shown that the injectors are not firing. So that means that IF there is an EDIS, then it's possible that the PIP signal isn't getting to the EEC, so it has no idea that it even needs to fire the injectors. That's why I bring it up.

Thats good intel right there. I'll chase the connection from edis to eec next. Thanks.

In reply to belteshazzar:

Just remember, if you replace the DIS module, you will need(IIRC) the dielectric paste to put behind it.

In reply to yamaha:

You know there are two different versions of that, right? I think you are talking about the DIS module that looks much like an overgrown TFI module.

There's another one that is a black rectangle with just one connector- and instead of being a single plane, the single plug comes out at a 90 from the module. I'm pretty sure this is mounted onto the chassis and not the motor.

That being said, the SHO was an early adoptor of DIS- the early one beign a "slow data rate" which I think is the TFI engine mounted module, a later one was the first "high data rate" which is the other module, and I'm pretty sure that even a later v6 was the first EEC with on board EDIS. This was over a pretty short time frame- things happened quickly.

'93 could have any of them, so look closely.

belteshazzar If you can't find it- find the coil pack, and trace the wires from it to the EDIS module. Be it the DIS module yamaha mentions, the high data rate EDIS, or even on the EEC board. Knowing that will pretty much tell us where the signal is coming and going from. And a possible error state.

In reply to alfadriver:

I only know of the one on the crossover tube on the intake, its possible the ATX is different. I've only owned one atx gen2 and had it for 3 weeks total before I sold it. MTX's had several other differences I know about.

this car has the edis module mounted to the intake crossover tube. there's a plug on either side of it, one black and one gray.

I checked the wiring between the crank sensor to the EEC, and the cam sensor to the EEC, and also the pip wire between the EEC and the EDIS. All good. :(

any other modifications to the car that you know of?

Have you checked the injectors for a bad one.....i have ran into it before

Well, he tested for voltage at each injector and they all have voltage. That tells me that an injector is not shorting to ground and pulling down the circuit for all 6 (or at least, it wasnt shorting when he checked). The only other ways an injector can fail would only affect that one injector, and the other 5 would probably still work. Even if an injector was shorted to power and fried an injector driver in the computer, there's more than one injector driver so that wouldnt explain the rest of them not getting cycled.

So, i doubt it is a problem with an individual injector. It seems to me that the computer is probably not even trying to cycle the injectors at all. Since more than one computer has been tried, it is probably because the computer is missing some input that prompts it to do that, or it is getting the wrong input on that circuit.

If i were currently working at a shop id be on Alldata reading all the 'description and operation' entries under the powertrain management section, trying to figure out what all inputs the computer needs/uses. Sometimes you can find a simplistic diagram that just shows the ECU's inputs and outputs. You can sometimes just look at an electrical diagram showing the ECU and work off of that, but it's nowhere near as obvious just looking at a circuit diagram what the computer actually does with that info.

One grounded could still read power but be berkeleying up the ground pulse for the rest. That is what mark is saying.

I'll rule that out tomorrow