Green Llama, 85 turbo T5 conversion

[Jordan]

Sent an ECU out of my car yesterday. It is setup for speed sensing, so you might not get full boost, but you'll be able to troubleshoot since it is known good C900 conversion with T7 valve modification.

[johnshan]

So, pretty sure ecu is not the issue. Still getting zero tach signal while cranking. Sparkplugs are dry after cranking. Could I have a lemon cps? I ended up buying an ecu from a T5 with auto trans. Jordan your diagnostic ecu is on it's way back... I need the wiring diagram of T5 harness to continue my trouble shooting.

[hutch]

If you are not getting any tach signal bounce then it certainly sounds like CPS problems, but, I couldn't get my car started once because one of the bolts on the 12v distribution block had worked itself loose and the fuel pump wasn't getting power. Very unlikely thats your issue since you said you can hear the pump prime, but if you're looking for ideas you never know...

Anyway, for a wiring diagram check out Appendix 2 on pg 124 of this document:
http://www.rossonex.com/SAAB/Trionic_5.pdf

Have you tried swapping the MAP and CPS harness connectors to see if they were switched up?

[Jordan]

I check for continuity for all the connections before I ship to be sure they are wired right, but there is always the possibility that the one of the pins backed out of the connector if it didn't *click* in, or a pin got jumped (still being in the right order but not in the right spot on the ECM).

CPS wires are clear, black and black on a thick shielded cable and the MAP connections are blue , black and grey on the new harnesses. Also you can try to set the CPS sensor out to 3mm airgap. I've seen a whole lot of variance in how the hardware processes the signal, 2mm is even a little close.

[johnshan]

checking through the connectors I found this. Hard to see in the picture but pin 9 is completely crushed-in and is surely not making the proper connection. Not sure if this is associated with no tach signal but still can't be good.

top row second pin in.

purple pin 9

[johnshan]

supposedly pin 9, connected to pin 18 at the ecu, is used for ion sensing to determine camshaft position and synchronizes the injection and ignition firing order. Jordan... how am I going to fix this connector?

[Jordan]

Is the terminal ruined or can it be pushed in more or bent back? Check to make sure you don't have a bent pin on your DI or something that would have gotten it all mushed up. With those big terminals I usually have good luck with being able to remove them with a large sharpened paper clip (if you don't have terminal removal tool) to press in the keepers on both sides and slide the pin out the back, I could send you a new terminal set. Of course I'd also be happy to re-pin and give everything else a once over if you sent it back to me.

Seems reasonable that that could be your issue. Definitely something to fix!

[johnshan]

I tried to bend the terminal back into place with no success, it's ruined. DI is still in good shape. If you could send me a new pin set that would be awesome! In a perfect world I would send you the harness, but with exactly 1 month before i'm moving down to California... hopefully driving my saab... I don't want to take chances on shipping things across the big ole US of A.

[Jordan]

sure, no problem. I'll send a few just in case.

[johnshan]

Ok, so I changed out the pin on the DI, much harder to get out than in. Checked every pin on the ECU to make sure they were going to the right place. as far as i can tell everything is in order and connected up.

Still no tach signal- still no start.

Went through some diagnostic steps and found out that i'm not getting power from the main relay with key on or during starting. Apparently this is pretty much only due to CPS wiring or non functioning CPS. I tested resistance on the CPS black wires to intake air temp black ( ECU ground ) wire, which has zero impedance, suggesting that there isn't a problem there. I replaced the relay with one from my bothers running 95, no difference. CPS resistance is 552 ohms.

I think I have a lemon CPS. Kinda the only possibility at the moment.

[Jordan]

Sounds like it, did you try another ECU as well? The CPS activates both the Fuel and main relays. What is your CPS gap set to?

[johnshan]

I have been trying both your prepared ECU and another one I got from the junkyard. I set my CPS out to 3 mm, but I'm going to play with some different gaps this afternoon. I'm going to check voltage at CPS and I think I might try jumping the relay if playing with different air gaps doesn't give me any results. I'e read that small resistances in the CPS circuit can lead to no starts, I'm going to do as many tests as i can before i ask for a replacement from Eeuro.

[Jordan]

if the CPS doesn't pickup the signal then it won't even fire the injectors (or plugs) even with the relays jumped. Right now I found a good gap to be between 2mm and 1/8".

[johnshan]

had my car jumped to a running car to ensure proper battery voltage and tested basically every air gap within the adjustment limit in < 0.5mm increments. checked what kind of AC voltage the CPS puts out and its less than 1 volt during cranking around 0.5 volts. been looking at the wiring for the CPS and I haven't found anything anomalous. Checked the CPS plug and made sure the pins were connected securely. main relay powers with key ON after de-powering the ECU but power doesn't return during cranking.

I think its time for a new- new CPS... unless someone can think of a electrical test for the CPS circuit...

[Jordan]

Looking at the Trionic guide,

Resistance between 1-2 540+-50 Ohm

Voltage at starting revs should be 2v @ 200hz