1997 Riviera - 3.8 Liter, L36 - 139,795 miles
I'm posting this question in TB because the problem hasn't been solved in other Buick forums. When starting a WARM engine (3800 Series II) the idle is unstable, rough and stumbles for 3 to 5 seconds, then smooths out. It runs GREAT otherwise and idles just fine at stop lights. Cold starts are no problem. The warm idle issue started this summer in June or July. I had the engine checked by GM Techs recently, and they reported low initial fuel pressure of 28 PSI (when it should be 48 to 55 PSI) then rising to normal. What is the likely cause? and how to remedy?
Thanks,
-Ed
I'm posting this question in TB because the problem hasn't been solved in other Buick forums. When starting a WARM engine (3800 Series II) the idle is unstable, rough and stumbles for 3 to 5 seconds, then smooths out. It runs GREAT otherwise and idles just fine at stop lights. Cold starts are no problem. The warm idle issue started this summer in June or July. I had the engine checked by GM Techs recently, and they reported low initial fuel pressure of 28 PSI (when it should be 48 to 55 PSI) then rising to normal. What is the likely cause? and how to remedy?
Thanks,
-Ed