Hello Everyone,
I have a question hopefully someone can answer. I have a 99 Chevy Silverado extended cab 4X4 with a 5.3 Liter. I am having trouble with it bogging down and almost stalling just after I start it and only when the temperature is 40 degrees or colder outside. Once it is warmed up it purrs like a kitten. I don't have a check engine light. I have replaced the TPS, the <NOBR style="COLOR: darkgreen; FONT-SIZE: 100%; FONT-WEIGHT: normal" id=itxt_nobr_1_1>CTS</NOBR>, the fuel filter, Cleaned the Mass airflow sensor, had the injectors cleaned twice. Once by a local shop and then again by the dealer who was trying to troubleshoot the same problem. I told them I had them cleaned but they said they had the ability to do it better. The dealer also updated the computer. I still have the same issue and was hoping someone might have an answer. Thanks in advance.

 

99% chance it needs intake gaskets. Very common problem with 5.3 can cause exact problem. Gasket has actually been updated, the new set is green. Once the truck is warmer they seal up.

 

The dealer went right to this and claimed they checked them and they were good. Is there a way to test them at home by myself?

 

No real good way to check unless you have a smoke machine. You can try to spray carb cleaner around it but that is not 100%. If you get a change in idle then you have a leak but if you do not it does not prove they are not bad. Even a smoke machine is not 100%Symptoms match perfectly, you may just need to take a leap of faith.

 

Well, I finally got it fixed. Let me tell you the process. I changed the TPS, CTS, Cleaned the fuel injection system twice, I changed the intake gaskets and the fuel pressure regulator and after all that I still had the problem. I tested it and had 30 PSI fuel pressure only when it was cold. I finally broke down and replaced the fuel pump and all is well now. It feels like I have more power now and it runs great. I have never had a fuel pump act this way. Usually they hard fail and just die. Anyways I am happy as a clam now that I got my truck back to normal.