1996 Olds '88 won't start when cold

[Jeffress77]

Hey everyone, I am new here. I hope you can help me!.

Here is a little history of my car.

My 96 '88 with the 3.8 L had a fairly extensive tune up in the spring of 2006, when it had 55,000 miles on it. I personally changed the fuel filter, coil packs, plugs, wires, and flushed the coolant and transmission systems. The car had recently had the water pump replaced, and I also changed the starter. During the summer of 2006, I experienced a problem with upper intake manifold plenum warping. I changed both upper plastic and lower aluminum intake manifolds and related gaskets and also chaged the EGR valve. My problems were all solved, and I had a practically new engine until recently.

Now, my car has 112,000 miles. My car absolutely will not start when the air temperature is under about 35 degrees. The car will turn over well, and the battery power is strong. For a short a time while attempting to start it will pop and lightly backfire, but to no avail. If my car is pushed into my heated garage, it will start perfectly fine after about 30-45 minutes. If I keep my car in a warm environment, it starts and runs like new.

I originally noticed a problem during sub-zero (-14 fareinheit) temperatures during the winter of 2006, one instance where the car would not start until it had warmed up. My intial thought was that I gotten moisture into the fuel system, which had frozen in the extreme cold. I added a fuel system antifreeze and made sure the fuel tank was full and I didn't have another problem until this winter.

This winter, the first night that we reached temperatures less than 30 degrees, my car did the same thing. I tried and tried, but the car wouldn't start. It turns over just fine, but it will not run. Once I pushed it into the garage, I didn't have another problem until I decided to leave it overnight outside for another trial. THIS TIME I HAD A COMPLETELY FULL TANK OF GAS WITH FUEL LINE ANTIFREEZE/MOISTURE REMOVER. It still didn't start.

When the car has started, it runs perfectly, and I can leave it parked in freezing temperatures for 4-5 hours with no problem, but if I leave it parked any longer than that (overnight)...IT AINT GONNA START!

Now, I do all my own mechanical work, and I know these G.M. 3.8 engines pretty well. But this one has me stumped a little! I have pretty much ruled out fuel line moisture, because it isn't going to freeze at 29 degrees in 8 hours.. that I know. The only thing I can think is inadequate fuel pressure/pump...BUT WHY ONLY WHEN IT IS COLD OUTSIDE?

Sorry to write a novel, but hopefully this will answer some other questions you may have when trying to answer mine!

-Justin

[Mickey#1]

Low fuel pressure is a possibility, you may not be getting a rich enough mixture when it's cold. I'd also check the coolant temperature & intake air temperature sensors. You can check them with an ohm meter or with a scanner.