1999 Tahoe with intermittent trouble starting

[JoeytheTinMan]

I'm having a little problem with my 1999 Tahoe. Every once in awhile, I'll turn the key and it will start up for one second then die. The one second it runs for, it doesn't run strong but sounds like it's struggling. Sometimes it will do it again a second time then stay running on the third try, sometimes it'll stay running on the second try, but when it stays running after the initial failure it sounds like it's not running right, sounds like it's really struggling. Then the next time I start it up later it will be just fine, no trouble at all. This might happen once every one or even two months, but sometimes a few times in a week, so it seems really random. I gave it a tune-up with new cap, rotor, wires, plugs, ignition coil, and ignition control module, and that didn't fix it. I changed out a couple bad 02 sensors, which didn't fix it. Changed out the fuel filter recently too.

Anybody have any suggestions for what the possible culprits might be here? Things I should check or test? The engine also makes a little bit of a whining sound when it's running, that gets louder when it's revved and quieter when it's not. The sound follows the throttle perfectly, almost sounds like a vacuum leak. Got a propane torch to see if I could find any leak.

Any suggestions would be greatly appreciated!

 

[gin_road]

Check the cable connectors on your ECM. I have a 95 Tahoe and a 95 Yukon, The Tahoe transmition would not shift out of 2nd, and then would not start. Found fuel pump was not running. Pulled ECM and found corroded pins. I checked the Yukon too and it was the same.

 

[RED TAHOE LS]

Joey, welcome to the forum from Georgia, glad to have you.

Air plus Ignition and Fuel are what makes any engine run. You've cleared the majority of the Ignition, water is heavier than fuel and will settle in the lowest part of the gas tank, Ignition problems are NOT NORMALLY ERRATIC, Fuel is. I think it's time to check the fuel tank like draining it. You got no idea what amount of water is in the fuel tanks where you buy gas, $hit happens.

David g...........

 

[bunchz71]

mine would do this. I ended up replacing the spider injectors. Fixed my problem. Do some more reading on some of the other topics and it could possibly be a leaking fuel regulator under the intake cover, or leaking spider injectors, causing the engine to flood when its cold.