69's MFI cold start problem...now ignition issue ?

[SFE]

Some information about my "troubleshooting process" !

Since I've reinstalled my genuine BHKZ (after cleaning all connexions especially the brown's ground wire) and changed the spark plugs, the car is still quite difficult to start when cold but eventually it starts all the time.
So I'm quite happy with that but anyway I will send my injection pump for an overall check up and I hope that will fix all other issues (cold start, too rich at idle, ...).

I've also the option to put NGK BP7ES instead of the 8ES which are installed in the engine so far.

Any other advice would be welcome

[SFE]

Problem solved…the start solenoid on the pump (which is only on 2.0 liters MFI E/S) was not working properly !

[edmayo]

Glad to hear the problem was found. That's also called an enrichment solenoid that I mentioned back in post 10. Did the pump rebuilder find the solenoid problem?

[SFE]

Glad to hear the problem was found. That's also called an enrichment solenoid that I mentioned back in post 10. Did the pump rebuilder find the solenoid problem?

Yes he did and at least that problem was solved !

But when we put the pump back in the car after the rebuilding we were unable to have the engine running as it should…
We had to richen up the rebuilder factory settings on the partial top screw by 6 clic which seems to be a lot AND the idle was unstable at 900 +/-100 rpm whatever the adjustments we did.
So we decide to change the injectors……it improve a bit that’s it.

So we had to send back the pump to the rebuilder to let him check it a second time and I’m waiting for the result.

If he find no error in his work I don’t know what to do because everything has been changed on the car !!!

[edmayo]

Just so you know, it is normal to have to reset the pump after a rebuild. All they can do is set to a standard based on a number of assumptions. They don't have YOUR engine to set to, and each one is different, they can't know whether all of your linkage is set correctly, or what spark plugs you're using, or your ignition components,,,,so many variables. I always have to do a pump set procedure.

[raspy2point2]

When I got my car back from a rebuild, it would stumble and buck on low rpm's in 2nd gear. I told my tech about it and he said the MFI pump needs to adjust itself to a base setting before he can further adjust the pump. He said drive it for 500 or 600 miles and then bring it in. When the 500 miles were done, the pump smoothed out on its own and now drives smooth all the way through the RPM's I would say drive the car as much as you can before making other changes to the system. Chris

[frederik]

Ed, what do you mean with "pump set procedure"?

[SFE]

Very interesting !

[edmayo]

Ed, what do you mean with "pump set procedure"?

We hook up an air/fuel ratio meter and drive car and adjust pump as necessary, starting with the load setting and finishing up with idle settings.

[frederik]

Got it! That made all the difference to how my Targa was running.