T+ lh 2.2 fuel enrichment question

[TmB]

I have a 86 740 with a +t done by the last owner he could never get it to run right. I know the turbo computers use the knock sensor for fuel enrichment unlike the NA cars. Can I just disconnect pin 3 on the TPS or do I also have to run a wire from pin 12 on the EZK to pin 15 on the fuel computer? I feel dumb that I can’t find a straight answer with the power of search.

 

[swedishK]

Yes, disconnect pin 3 on tps, and run wire from 12ezk to 15ecu

 

[esmth]

i don't think just that will fix any running issues. what specifically is wrong?

 

[TmB]

Yes, disconnect pin 3 on tps, and run wire from 12ezk to 15ecu

Thank you!

 

[TmB]

i don't think just that will fix any running issues. what specifically is wrong?

Don’t run well under boost feels like it’s not getting enough fuel and it ran better (before I did a bunch of work) on a NA computer

 

[volvosruinedmylife]

I never did this on my plus t. Haven't driven it a ton, but the air fuel seems fine. I thought it was a straight swap of the ecus. Opps!

 

[Cwazywazy]

Don’t run well under boost feels like it’s not getting enough fuel and it ran better (before I did a bunch of work) on a NA computer

What injectors? What fuel pressure regulator? (Both are different between turbo and na)

 

[TmB]

What injectors? What fuel pressure regulator? (Both are different between turbo and na)

850 turbo injectors at 42 psi

 

[bobxyz]

What are the EZK and ECU Bosch part numbers? They should both be turbo versions.

Check your pin numbers and wiring. The TP31058 1987 740 Greenbook (for LH2.2) shows:
ECU pin 12 to TPS pin 3 for NA
ECU pin 12 to EZK pin 15 for Turbo <<< this is backwards of what you've posted