My 2004 Tahoe has had issues last winter and this winter with a few things that I am trying to narrow down. It will not start if less than 1/2 tank and temp outside is <20. My coolant level says low within 4-5 days of filling it. I lately am able to mildly smell the antifreeze "burning". I thought it was an issue with the fuel tank needing replaced before the whole coolant issue arose. I took it in to be checked several months ago and they changed the oxygen sensor and said it may be the fix for it. It wasn't. When I am stopped at a light my truck "jumps" and RPMs go way down and back up to normal. It also seems to do same thing when I even take my foot off of gas and kind of loses power unless I have my foot on the gas. It did this somewhat last winter but this winter is worse. It stalled on me 4 times the other day at lights. Again, this only happens when it's cold out. Appreciate any advice or thoughts! Thanks!

 

For that smell of coolan burn, is there smoke coming out of the exhaust!? And you may have a faulty fuel pump!

 

Alfredo!!!!!! Thank you so much for responding! I have been waiting for help on this. Nothing is smoking but I am fairly sure I have a leak somewhere throughout my coolant system. There is a spot of liquid on the ground when I move my parked vehicle. I am not sure if this leak would have that much bearing on my truck not starting with less than 1/4 tank. I have wondered about the fuel pump. I just don't want to jump the gun and put that kind of money into it if that's not the issue. A diagnostic was done on it a few weeks ago and they said it was the water pump but would that really cause this issue? I also wonder if it is just a leak causing that error code and not the entire water pump. Again, I don't want to jump the gun with replacing things that don't need it. UGH! This truck has been a pain the past year and today, the sunroof refuses to close. Thanks for any advice!

 

for a truck of that age; replace the waterpump while your replacing the water pump gaskets.


the hunting idle could be a dirty throttle body or leaking intake gaskets. What is the fuel trim at idle and at 2500rpm? If its leaning out at idle but fine at 2500rpm; there is a vacuum leak from the air induction system(anywhere rear of the maf sensor to the intake manifold).