Investing in GuzziDiag software and hardware, I attempted to tune my 2001 California Special, (Power Commander had died on me some years before) and I felt performance was deteriorating after 21 years of just general cleaning and rigorous maintenance. I found that the TB’s had some serious play in the L/H TB. New bushes and seals fitted to sonically cleaned TB’s, injectors checked and cleaned, I had another go.
Although I initially struggled to get the idle down to 1100RPM, (I noted that the CO trimm was originally set at -35, I changed this to 0, don’t ask me why) after multiple attempts at getting 1100RPM I reset the CO Trimm to the original -35. Finally, the Cali seemed to be running much better, more responsive and seemed much happier!
After being laid up over the cold and dreary winter months, I finally sprang into action on a warm pre-spring day and tried to start my 2001 California Special, ha, flat battery.
Battery fully charged and I found it very difficult to start (degraded fuel, I thought). Eventually she fired up, popping through the exhausts and spitting back through throttle bodies (TB’s). I should imagine the neighbours thought there was a shoot-out taking place in our little close. Changing the spark plugs made no difference. Very weak fuel mixture, me thinks! Clean fuel and a quality TB/injector cleaner made no difference.
After rereading the TB setup procedure and checking that all readings were within the recommended tolerances, although starting and running better, the Cali was still spitting back through the TB’s at low RPM and popping on the overrun. I had a spare TPS, so sprayed this and the original with contact cleaner and fitted the spare TPS, I found a slight overall improvement after every attempt at eliminating the spitting back and jerky acceleration and cruising at low RPM, but all to no avail.
I eventually disconnected all electrical plugs, relays and fuses and sprayed them with a cleaner, the oil temperature sensor was quite corroded and some of the relay blades were slightly corroded.
Is a faulty TPS causing these problems?
With the original TPS fitted and following the factory procedure for setting the TB’s from scratch, with a slight change.
1) Set disconnected L/H TB to 150mV.
2) Adjusted TB idle screw to read 520mV.
3) I then increased the L/H TB reading to 620mV by releasing and moving the TPS.
I found the running improved, but this didn’t eliminate the poor running experienced earlier.
Repeating number three above I released and moved the TPS to read 720mV.
This setting eliminated the poor running experienced prior to this, However, I need to run the Cali much further and longer to ascertain that other important factors are not adversely affected.
Are the above symptoms indicative of a faulty TPS?
What are the symptoms of a faulty or broken TPS?
Any comments or suggestions that will lead to the elimination of these problems and allow me to revert to the factory settings will be much appreciated.
