CIS startup problem

[htbetz]

My 74' 2.7L cranks over and fires immediatly in any weather but dies out within a couple seconds of firing. It takes about 4 tries then it stays at fast idle fine. It starts and runs perfectly when warm. I checked most of the stuff in the Bosch book and everything seems to be in spec. Anything else I can look at?

[marcesq]

Not a fix, but a suggestion to get to the root of the problem. When you first go to start the car cold turn the ignition switch on without engaging the starter (let fuel pump run a few seconds) then turn the key. If the car starts without stalling it may be that the fuel pump is going bad, but there may be other reasons for the problem that I don't have experience with.

good luck.

[wckrause]

Did you measure the control pressure at cold start? Is that within spec?

This sounds like the typical CIS cold start problem of being too lean when cold. The cold start injectors pump in enough extra gas to fire up quickly, but then the WUR isn't enrichening the mixture enough to keep it running.

[stlrj]

Your airbox might just have a crack at a seam that you will not see or if you're lucky the rubber boot that connects your throttle to your air flow meter could have popped off.


Joe