2002 9-3 SE : original DIC repair/modification

[michel6244]

SAAB 9-3 2002 SE
DIC (Direct Ignition Cassette, part # 55559955) DOOMED REPAIR ATTEMPT
09/2017

TBN : The car was apparently fitted from new with the DIC part # 30583218.
This first version was plagued with insufficient thermal resistance of its electronic circuitry, which could create dangerous driving conditions. Its replacement by version 55559955 was recommended by SAAB around 2005 - 2006.
When I purchased the car (second hand), back in 2006 (56 K km on the clock), it had already undergone this recommended upgrade.

From 233 K km (about 200 K km in service), I began to have now and then spurious engine electric management alarms (the dreaded little orange engine alarm in the dashboard !).
The SAAB specialist in the area was called for help with his TEC 2 analyser, and indeed the error code message we got was P1312 : there was a problem with the ignition on the (1 + 2) group of cylinders.
At about 234 K km, I first inspected the plugs, which were found all four to be of a correct aspect and colour. The gaps were a little high, so I brought them back to the recommended value of 0,9 mm. Also, the torque was found to be too weak (about 12 Nm), so they were torqued back to 20 Nm.
The problem was however not suppressed, so something else was wrong.

I thus inspected the DIC itself. A transverse crack, about 5 cm long, was observed in the bottom, plastic part, but between rubber prongs # 3 and 4.
The cassette’s two components were readily separated from each other by removing eight M6 assembly screws.
No hints of any coil cooling oil leakage, nice clean aspect of the epoxy bedding, etc…
But, unlike the three others, the bottom contact of the #1 coil showed a gummy aspect, and slight but uniform oxidation. This implies a poor electrical continuity to the #1 spark, and therefore logically accounts for the occasional misfiring error code.

I also checked the lengths of the springs which make continuity between the coils and the spark plugs : they were all four of about 37,5 +/- 0,2 mm, so I stressed them a trifle, to bring their rest length to about 38 mm.
I cleaned all four coils contacts with fine emery paper, then sprayed them sparingly with a chemical electrical contact cleaner, before re-assembling.

While I was at it, I also carefully worked the two ends of the DIC aluminium alloy base cover (as shown in the pictures below) with a small hand grinder, to enable some cooling air flow between the DIC and the two cam banks. Purpose being to help in taking a little more heat away from the system, by air convection.
I suspect indeed that when under way, there exist small, local air pressure differences under the hood, which would help in establishing a cooling draft around the DIC alloy base.

Reducing somehow the DIC operating temperature, if only by a few degrees, is all but detrimental to its reliability.
Automotive electronics maximum admissible operating temperature is 125 °C.
We here have an application that is not far off this limit, when the going is tough.

michel6244







UPDATE / FOLLOW UP

500 km or so have been covered without problem...

Alas : re-appearance of the fault again this morning !
On looking closer, the cylinder head plug #1 pit area shows a slightly oily aspect.
Come to it, I now witness the same, well known problem, that has already been described at length elsewhere : a leaking coil cup.

Worthwhile mentioning :
1) I have to admit, this problem has probably started quite a while ago, the draining has thus been very, very slow : I now can remember I first observed a lightly oily #1 plug already about 50 K km ago. I first thought it had to do with engine oil from down under.

I have finally opted for installation of a new, genuine Saab DIC : it was waiting in my trunk for installation anyway (just in case :-).
2) The cooling oil leakage path seems to be along the coil bottom contact passage. This explains why this contact was found out to be gummy in the first place...

[swisssaabist]

Well could be useful for others like me who have two used DIC So for now you have tested it ? I mean drive with it ?
I speak French too.