Swirl Pot

[greyV8pete]

Re: Swirl Pot

After an ECU reset a quick check today with the Ecumate and with the engine running gave a read out Tune White + Cats which is encouraging.

My latest thought is that as the problem has occurred both times after the Kenlowe 2000 has cut in a few times, is that the sudden voltage drop (20Amps running so a hell of a lot more from stationary) is triggering the ECU into going into limp home mode. I want to try my Sierra heater resistor in circuit with a bypass switch to create a kind of soft start for the motor to minimise the initial voltage drop. I have also still got the original fan so could always refit that for a trial. Meanwhile Stoneleigh is fast approaching! Peter.

[greyV8pete]

Re: Swirl Pot

Ecumate gives readings with engine running! Have refitted my old Kenlowe fan which pulls less Amps, doesn't restrict the radiator core as much and keeps the engine just as cool as the high output Kenlowe. Today I fitted a new Sytec HP fuel pump and increased the fuel hoses and filter all to 10mm bore. Just been for a run and the persistent stumble now sorted. Much better acceleration too and the pump is much quieter than the old one. The old pump must have been on the way out for some time. Sooooooooo I will be driving it to Stoneleigh tomorrow! See you all there. Peter.

[greyV8pete]

Re: Swirl Pot

Further work with the Ecumate over the last week has produced the following results.

I realised that the throttle pot and the Air Flow Meter voltages haven’t been checked for ages, especially since setting the ignition timing with a strobe at 3400 RPM, fitting the new HP pump and the new fuel pressure regulator, so back to basics seemed a good idea.

I have read and re-read the Ecumate instruction manual a few times, always a good place to start! Steve Heath (Ecumate) mentioned incidentally that faulty parts don’t always flag up a fault code. For example a coolant temperature sensor that is rather inaccurate won’t flag up a code but one that is way out, or failed, will flag a fault code. Interestingly after blanking off the idle control valve to set the base idle, the Ecumate always flags up a fault code for that component, which is reassuring.

I have now set the throttle pot at 0.4v which is theoretically mid range. This has enabled the base idle to be set at the Optimax chip recommended 550 RPM for the first time ever. The idle speed is now 750 RPM as recommended and the base idle screw is only ½ turn open which is also a good sign. The AFM is running at about 1.45v. This new throttle pot setting has allowed the idle to be much lower when the car is moving but has also set the idle threshold lower, down where it should be, so it also drops to 750 much more quickly once the wheels stop turning. This has almost eliminated the hunting and snatching that has always been an irritation ever since I had the car.

Impressions from the latest road test are that it’s a totally different car to drive! More flexible and a “softer” response, but if you use the right foot in anger it really wakes up! The V8 exhaust note is even deeper than before! Bonus!

Still some work to do to check the CO readings from each exhaust pipe and maybe fine tune the AFM to make sure it isn’t running too rich.

Watch this space! Peter.