hard to get started in cold weather!

Hello everyone I am really stumped! I have a 2000 s10 pickup 4x4 with 130000 miles my problem is it starts up perfect and runs great in the summer but as soon as it gets cooler outside it is very difficult to get started! Once it does start runs perfect. This has been happening for the last 3 years. Is there a sensor or something that adjusts the fuel mixture or controls an elecrtic choke of some kind? The fuel pump went bad 2 years ago i replaced it but still has this problem. It has the 4.3 vortec engine 4x4. Any help on this issue would be greatly appreciated. Thanks.:banghead:

Tune up?
Have you checked the fiuel pressure?
Fuel pressure has to be up to specs of 65 lbs on a cold start.
Any check engine lights?

Yep, like MT-2500 says, check the fuel pressure, here's where.

http://i131.photobucket.com/albums/p288/Clunk_/Image026.jpg

Now for the importatnt question, what '69 Olds you do you have?:grinyes:

I'll check fuel pressure but I dont understand why it is fine in the summer even after sitting overnight. Seems like a choke problem since its only happens when outside temp drops below 50 degrees. But i dont know what act like a choke on these newer computerized engines. I am assuming its some kind of sensor but I just dont know which controls the air fuel mixture.If it turns out to be the fuel pump again its bye bye time cause way too much money for that again. Just did that 2 years ago it went twice in a 6 month period!







BTW to Chris Stewart It is a 69 442 convertible that I will probably never finish restoring since you have to be independantly wealthy to restore a car nowadays.LOL

I'll check fuel pressure but I dont understand why it is fine in the summer even after sitting overnight. Seems like a choke problem since its only happens when outside temp drops below 50 degrees. But i dont know what act like a choke on these newer computerized engines. I am assuming its some kind of sensor but I just dont know which controls the air fuel mixture.If it turns out to be the fuel pump again its bye bye time cause way too much money for that again. Just did that 2 years ago it went twice in a 6 month period!







BTW to Chris Stewart It is a 69 442 convertible that I will probably never finish restoring since you have to be independantly wealthy to restore a car nowadays.LOL


Fuel pressure problems are the leading cause of no start cold.
But bad fuel pressure is not always a bad fuel pump.

A fuel pressure test first and then a good engine capable canner read out should show your problem.
Also how many miles on last tune up?

The only true test on a fuel pump is to check the direct fuel pressure from fuel pump.
A quick test is to block off the return line and see if fuel pressure comes up to 75-85 lbs.
But do not run the pump at full pressure very long.
Also when testing fuel pump and pressure you need to tape a gauge to outside windshield or outside mirror and drive it on the road for 20 -30 minutes
until the pump gets has run a while to check for a pump fading out after hot.

Hard to start cold or hot and fuel pressure testing guide lines.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
If pump has full pressure with return line blocked and low pressure without it blocked most usually the fuel pressure regulator is leaking or not holding pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak in system.
Post back fuel pressure readings.

BTW to Chris Stewart It is a 69 442 convertible that I will probably never finish restoring since you have to be independantly wealthy to restore a car nowadays.LOL

That's ok, just keep trying...I just wish I'd kept my my hardtop...what's worse, I only have 1 picture and not a very good one at that. I check eBay every now and then to punish myself . The ones that are silver w/black vinyl top w/clutch pedal put a tear in the eye.:smile: