Hi. My '94 850 not-a-turbo sedan keeps setting the check engine light on. The only diagnostic trouble code I can find is 411 on A6: "Throttle position (TP) sensor signal from fuel injection system missing or faulty."

I've probed the TP sensor signal at the the LH 3.2 MFI control module connector, which checks the sensor, connectors, and wire. It is exactly in spec: 1k Ohm at idle, 2.4k Ohm at full throttle. I cannot tell from my wiring diagram which wire carries the TP sensor signal from the 4/45 LH control module to the 4/10 EZK (DI) ignition system control module.

(...And boy, do I wish the copy, which I bought from Volvo's publication department, of Volvo's wiring diagram publication TP3903202 was not a photocopy of the original! Some of the details are very hard to read.)

The car seems to drive OK. No hesitation at idle, city, or highway speeds. Fuel consumption seems higher, but I have no hard measurements yet.

I've cleared this DTC over 3 times but it keeps coming back.

Any ideas?

Thanks!
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-- Bruce / '82 244 (323k miles!), '86 745, '87 760Ti, '94 854