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My 1998 900s has been acting up latly, and the problem is only getting worse.

Rewind to 2 years ago, I noticed that after an automatic carwash the engine would misfire (once every 3-6 seconds) while idling for a few mins until it all dries up. It was obvious that I had a ground somewhere, be it ignition coil, distributor, plug wires etc..
Anywhoo the problem got rectified by not going to automatic carwashes :confused: :lol:

At about 3 months ago, randomly while accelerating I started expiriencing complete power loss for 4-6 seconds. It would be as if I had drive by wire system, and the computer throttle position sensor was way off. For example I would slowly start accelerating from a stoplight, and about 40kph all of a sudden complete power loss and engine just normalling idling. I'd press the gas pedal to the metal. Nothing for a few more seconds, engine still idling. Then BAM wheel spin.
I did not sense any misfires at all during these episodes, the engine was perfectly idling.

Then it hapenned during uniform highway coasting. I would be going at 120kph when I would loose power for 4-6 seconds. No wierd stutering or misfires. As if the fuel pump only gave enough gas to idle.

Then as of last week sometimes I would come to a stop at a stopsign press gas, and the engine would start to stutter real bad (I usually idle at 900-1000rpms), but the rpms would dropp to 500-600 range. Hard to say if it was misfiring or if fuel pump was having issues. I'd kick it in neutral, it would still misfire for a few seconds, then return to normal ~5 seconds later.

Then today during haighway speeds a really wierd thing hapenned. While accelerating at about 100kph the engine started to completely loose power, return to full power ultra quikly, like twice every second. Basically it would be jerking the car fairly hard twice a second.

I know from the write up it feels like I am loosing spark somewhere along the line, but could it be the fuel pump? It would explain the lag in acceleration after initial start-up.
LOL, knowing my luck it's prolly both ;p

Anyhoo, am just at work killing time, any suggestions are welcome though.
Will initially change rotor cap, plug wires, coil.
 

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Losing power after the car wash was the first clue there is something wrong down there where the coil is - also the wires.

These must be clean and unaffected by moisture..
Spray with polyurethane ??

How about the age and miles of the service items (wires, plugs, maybe the rotor and cap)
The coil has ohm values at its terminals - maybe this is in the book..

service as necessary
test
diagnosis
repair as necessary
 

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I recently bought a 1998 900s vert. Car is great for the most part. I too get this occasonal power loss.(once every couple of weeks) usually in second gear I get complete engine power loss for like 3 seconds then it comes back. Is this considered a misfire. I am going to change plugs,wires,rotor,cap very soon as I have not yet since I got the car and am not sure the last time it was done. Any ideas?? Also I know my exhaust has a rusted out hole. Would that play a factor?
 

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Me too

Have had same problem with 94 900s 2.3i. My Saab garage chaps have replaced rotor, plugs etc. fault still apparent. The current theory is that I need a replacement ECM. If anyone in the UK knows where I could get hold of a cheap 2nd hand one I'd be chuffed to bits.
 

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I suspect the transformer (coil), if the hi-tension leads have been changed(these used to be a service item), I do not know about now.
I never renewed anything, other than the plugs, with the old '88 Honda..
Many American cars have had to have the coil-pac changed...
 
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