CIS Fuel Injection Quandry


#1

1978 Volvo B21 engine has excessive control pressure. I’ve bebuilt 3 CP regulators and tried two commercially rebuilt units all with the same result. Could a non-functioning (blocked)frequency valve be causing this? Cold pressure should be 25psi(ish)warming to 50ish. I’m getting 40psi warming to 62psi.