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4 blinks usually means that there's a knock sensor Posted by RS [Email] ![]() ![]() ![]() In Reply to: Engine Light Saab 900, Claudia, Tue, 19 Sep 2006 20:14:14 Members do not see ads below this line. - Help Keep This Site Online - Signup |
fault or you got a batch of really, Realy bad gas.
The ignition control module has backed off the spark advance as far as it can, so it's telling you that something's up.
It often something simple like bad (or incorrect) spark plug wires. If they're so old that they let spark go to ground or if they're not the original plug wire manufacturer, they will put out radio fequency pulses that the ignition control module picks up on the knock sensor wiring and interprets as knock. It tries to back off the spark adavance until it doesn't detect knock but it can only go so far. Once it reaches that limit, it triggers the check engine light, calling for help.
If somebody just put new, cheap spark plug wires on, you'll want to get your old ones back and put them back on or get a new set of Bougicord (that's the brand name) wires and put them on. They're available through site sponsors (look down on the bottom of the page) at fairly reasonable prices. We can talk you through putting new ones on.
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