‘74 1.8L L-Jetronic Cold Start Low Idle, Mystery solved! Options

[Van B]

Ok fellas, here’s the run down Aux Air Regulator (AAR) and Cold Start Valve (CSV)/injector both work fine. Many of you have also been keeping up with my high idle issue that we figured out.

But yet, when the car is cold, i.e. room temp, I don’t get the high idle I should on start-up. Instead she cranks a bit and then lumbers to life. Idle lopes around 700-800rpm and then smooths out as it warms.

In all other aspects of operation, the engine seems to be pretty happy.

Thoughts? Experience? (IMG:style_emoticons/default/confused24.gif)

-Van

See post #419 on page 14 for a synopsis of the outcome.

[wonkipop]

i've just remembered something too about the hose from the plenum to the AAV.

i redid all my vacuum hoses at recommission time.

except for the crankcase vent hose (could not get one) - but it was still ok and doesn't leak.

what i found was that the short hose connecting the AAV that i put on was collapsing because it was such a tight bend. certainly when i had everything hooked up and i revved the engine it sucked in and collapsed completely.

so i took the replacement hose off and put the original back on which was still in good condition. tested for leaks and it didn't leak anyway. the original hose was preformed to the tight curve and does not collapse either from curvature or engine vacuum.

again though, despite the hose not collapsing - i do not have fast idle so the hose is not playing a role in the case of my car.

but if that hose has been replaced and it is constricting then that would inhibit the AAV valve in some cases.