Engine miss after sitting for two hours post short drive

Talk and Tech about turbocharged 924/944/968 cars
ROB III
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Drove my basically stock 89 Turbo for a short run to check for any issues after it sat for two weeks, all good.
Next day, I did a 5 mile run with a small hiccup but then clean run once fully warmed. Parked for two hours and when I restarted it had a terrible miss and the whole car vibrated with a couple coughs almost like bad timing.
I checked the plugs when it cooled down, looked acceptable, not wet, not carboned...
Plugged in a new DME, no change.
I once had a similar sound/feel and unplugged TPS and plugged it back in, which fixed the issue then, but no impact this time.
It starts easily, but runs terribly, no tach bounce.
Thoughts?
Thank you
Rob
89 944 Turbo
Musik-Stadt Region

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walfreyydo
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Sounds like you might have a miss on one or more cylinders. I would start by first ensuring every spark plug is firing (or alternatively if each port on the exhaust manifold gets hot). Determine which cylinder may not be firing and go from there. Usually one cylinder missing is a spark plug/spark plug wire, cap/rotor, or injector issue.
89 S2 Variocam, Megasquirt DIYPNP
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ROB III
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Update to my miss issue and also being mindful of some issues NCGermerican had with his Kroon harness install issues, I thought I'd share what my result was......a dead plug.
So i'm embarrassed to admit it was so simple but I looked at the pugs, wires, DME...all seemed fine. Was frustrated so I took it to a recommended mechanic (also needed A/C recharged) and it was a dead plug. He LOOKED at them as well but had a plug checking instrument and it was just dead. They were new plugs with less than 1K miles on them and the number 1 plug just gave up the ghost. Changed out the plugs ( all to be safe?) and runs just fine. Sometimes it's the simple things that are easy to overlook and assumed OK by visual check....live and learn.
Rob
89 944 Turbo
Musik-Stadt Region

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