Okay, I have have an interesting problem that I can not figure out. I have a 1979 Tran Am with an Olds 403.
Long story short.....everything is new or within a couple years old (gas tank, carb, fuel pump, distributor, ignition coil, valve job, etc, etc, etc.).
The problem....the vehicle bogs upon acceleration BUT ONLY WHEN THE OUTSIDE TEMPERATURE IS OVER 90 DEGREES!!!!?
And only after the vehicle is good and warm. It exhibits NO symptoms of vapor lock. It is not hard to start, there is no strong odder of fuel, etc. The only problem is that the vehicle bogs when taking off from a stop, primarily after idling for about a minute, and after 15-20 minutes into the drive.
The really strange part is.....it only does it during the summer. I can drive the car all fall, winter, and spring and the car performs great (I live in Phoenix AZ)....but when the outside temperature is over 90 degrees I experience intermittent bogging when accelerating from a stop.
The vehicle has done it every summer since I got it from a friend in 2014. The car is a daily driver and I am restoring as I go. To date I have over $12K in the restore and each summer I try keep having this same issue.
I am thinking maybe heat soak? I even replaced the ignition coil a couple days ago and still the same problem.
Has anyone else experienced anything like this?