The TR SPC figure is correct (if a little unclear): https://www.ferrariparts.co.uk/diagram/ferrari/testarossa-tr-90/014-secondary-air-pump-and-lines-(for-us-and-ch88) hose 43 connects to port 2 on the electrovalve hose 44 connects to the differential pressure switch hose 45 connects to port 1 on the electrovavle port 3 of the electrovalve is left open to the atmoshpere Image Unavailable, Please Login
My notes have the US TR injection ECU, Ferrari PN 125134 = Bosch 0280800144 I believe all US TR use the same injection ECU, but yours should have a label on them showing the Bosch part number: Image Unavailable, Please Login
K-Jetronic (without Lambda) early euro TR do not have injection ECUs. KE-Jetronic (with Lambda) US TR use the Bosch 0280800144 ECUs. KE-Jetronic (without Lambda) euro TR use Bosch injection ECUs (but I don't know which one, and it has a different Ferrari part number than the US version injection ECU).
OK, I thought I had found the issue with a minor manifold gasket leak but after fixing it, it still misses and surges under full load. I did check the potentiometers and they tested OK. I tested the protection relay and it was good. Both fuel pumps put out 5.5lbs. I rechecked the mixture and throttle settings and they are good. I did take it out and experimented with it a bit. I realized that if I only give it about 65-70% throttle, it is fine but by giving it a little more it starts to mis-out and stumble. Again, it does not do it when its cold and it does not do it when hot and not under load. How do I test the bimetallic thermoswitch, and the water temp sensor? Could this be caused by a barometric capsule? Is there a way to test the FI ECUs?
Have you confirmed that the WOT portion of the throttle microswitch is working? Terminal 3 should be connected to terminal 18 at large throttle opening (i.e., terminal 5 at the injection ECUs should be +12V at large throttle opening). Measure the voltage on one of the O2 sensors single wires at warm idle when plugged in = it should be "wandering" between 0.1V and 0.9V (i.e., running closed-loop). If it just stays a fixed 0.5V = it's wrongly running open-loop. Already given in post #23. No, IMO (but the test for the barometric capsule operation is given in Diagnosis Sheet N. 6). Diagnosis Sheet N. 6
Looking at the workshop manual. page D-105 #14 is this the temp sensor? Image Unavailable, Please Login
#14 on page D105 is mislabeled -- it should be "Thermoswitch for coolant temperature (63/36 deg C)". #14 is the bimetallic thermoswitch (cold = closed = runs open-loop and air injection system "on"; warm = open = runs closed-loop and air injection system "off"). PS That schematic on page D105/D106 is a little incomplete for a US version -- better to use the US TR 509/88 wiring diagram Fig 3 (if you don't have the wiring diagram for an early US TR). Give a shout if you don't have a copy of 509/88 (but I've posted a link to it many times).
(Key "off") At the unplugged injection ECU (either one), measure the resistance between pins 1 and 5 in the harness connector: not WOT = should be infinite Ohms WOT = should be 0 Ohms (meaning maybe just a few Ohms maximum)
In reading the manual under symptoms it lists warm start control pressure too high after warm up. How is this checked?
There is no "warm start control pressure" in the US TR KE-Jet system (that only applies to the early euro TR K-Jet system).
I am getting 0 ohms between pin one and five on the fuel injection ECU at full throttle with key off. The engine is cold. Will that make a difference? I tried both ECU plugs
If at WOT throttle position = not the correct result. One easy thing you might do is unplug/replug the throttle microswitch a few times to wipe the connector contacts and then retest. (Being located above a hot cylinder head is a difficult environment.) Engine temperature has no effect on the WOT throttle microswitch operation (or mis-operation).
Looks like Everything to the ECU connectors when it comes to the throttle position sensor works. Now what?
Did you do something to "fix" the WOT microswitch operation, or was it just pilot measurement error (and it's always been OK)?
I think I am going to change out the water temp switch and thermistor as I have them and the originals are probably the originals. Can a TDC sensor or Tack sensor make a car do this? So far I have tested the TPS Illuminated all vacuum leaks Replaced plugs, wires, extenders, rotor and caps Tested the potentiometers Check and recheck mixture new fuel injectors Pressure tested both fuel pimps Removed the fuse box circuit board, cleaned and inspected checked all vacuum lines checked/cleaned all grounds unplugged all accessible plugs, cleaned and inspected Bypassed/tested the bimetallic switch tested/ replaced both o2 sensors Possible issues: Bad FI ECU Bad TDC sensor Bad Tack sensor Bad ignition ECU Any thoughts?
Bad FI ECU -- Maybe. Diagnosis Sheet N. 6 tests 12 thru 18 would do a lot to show if the injection ECUs are doing the right thing, or not, with the signal going to their EHA for various conditions. However, be very careful. If you accidentally short pin 10 of injection ECU to pin 12 of the injection ECU = blows up the injection ECU. And they mangled things a little because for tests 12 thru 18, you need the protection relay closed, not just key "on". Bad TDC sensor -- Unlikely Bad Tack sensor -- Unlikely Bad ignition ECU -- Unlikely
