A block heater is not necessary and would be a PITA. You really need to seek out a mechanic who understands the Bosch CIS fuel systems. You could have a cold start valve problem, but I rather doubt it. The failure rate on that circuit is very low. Wilthout having the car in front of me, I'm suspecting a faulty signal from a temp sensor or the car isn't operating off of the computer for some reason. I'm sure your mech has taken care of your other cars, but it isn't fair for either one of you to ask him to diagnose this car.

Post Script: Thank you very muck for posting exactly the year, make, and model of the car you are asking about. One of the pet peeves of the professionals on this site which sometimes means no answer to the question is yahoos who insist on keeping that information a closely guarded secret. One of the pros here always asks:" Is this A Ford or A Chevy."

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