Technical Fuel Injection Problem

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Technical Fuel Injection Problem

Jun 17, 2020
Completed mechanical restoration on my 1981 Fiat Spider Turbo (with Turbo delete). HAd a small oil leak at head gasket and ended up replacing the head gasket . Unlike 90% of the work which I did myself I had a local shop do that. Got it back and after a little tweaking it was running good but seemed to run rich. After a couple of drives and about 40 miles the car ran rough and was difficult to restart. I pulled the plugs and they showed the engine was way too rich. I replaced the plugs but the car still ran bad and now will barely start and run. I noticed that the Throttle plate switch was not connected to anything. I took a picture before the work was done and there is definitely a connector attached to a wire which I assume connected to the harness. Now I could not find a wire and connector that I could connect to the sensor/plate. The mechanic is positive there wasn't anything hooked to the sensor and actually marked it and took a picture of it. I did find a wire with a 3 hole connector coming from the wiring harness which is the same area wher that throttle switch is attached in my 1983 spider although there isn't a connector on the 83s wire. My assumption is the mechanic did disconnect that wire from the sensor and at that connection and then forgot and assumed they were both just unconnected. I orderd a connector for the throttle sensor and it has three wires which I plan to attach to the three wire connector that is coming from the wire harness.
I know this is a lot but I am seeking the following advise:
1)Does it sound feasible that the car could run decently for a short while until the plugs fouled to the point that it would barely run because of no connection to the Throttle plate switch/ sensor?
2) After changing out the plugs for whatever reason would the car still barely run?
3) Other then disconnecting the battery is there anything else I should do before connecting the Sensor to the existing three prong connector that is somehow wired to the same harness that I see on my other car. I certainly do not want to fry an ECU or do some other damage?
Any help will be greatly appreciated
these pictures show the sensor with no attachment and the dangling connector coming from the wire harness


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You say "Turbo delete". Just taking the turbo out with no ECU mapping/other changes is not likely going to work well.

If I were you I would try and find the circuits/wiring for the original stock setup and then you can work out what all the sensors etc. did.

A dangling connector needs to be traced back to it's original purpose/function.
Appreciate the response. The car had the Turbo taken off for years prior to me acquiring it. It has run fine for a long time prior to having the head gasket replacement completed.IT also had a valve job done at the same time and the head machined. I assume all of these cars should have a connection to the throttle plate switch but I don't know that for sure. If it does have to be connected, then I would be almost positive that the dangling connector coming from the same harness loop that my other Spider connects to must be the problem. Does anyone know of a reason that throttle Switch wouldnt need to be connected to something?