I have a 2001 Chevy Tahoe that has an intermittent starting problem. The car fires right up first thing in the morning, if it has sat for 4 hours or more, or if I’m running errands and it sits less than 10 minutes. During these starts, it fires up as it should with just a quick turn of the key and I don’t have to give it any gas. If it sits longer than 10 minutes, and up to 4 hours, it has a hard time starting. I have to crank the starter and pump the gas pedal a few times and it will start up in 5 seconds or so and I usually get a puff of exhaust coming from the tailpipe and a strong gas odor. It seems to me like it’s starved for fuel. I’ve changed the spark plugs, fuel pump, fuel pump relay, and fuel pressure regulator. I have never been stranded because of this issue but it’s more of an annoyance and I’m worried that I’m fouling the plugs from having to crank it so much. Any ideas?!?
I think you might have the exact opposite issue…you may have a stuck injector leaking fuel into one of the cylinders and thus FLOODING it. When you step on your accelerator you are allowing MAX airflow…which usually helps to blow out a flooded cylinder. You should NEVER touch the accel on any fuel injected vehicle…thats a NO NO… Back in the days of carburetors…SURE…not today however.
When you changed the plugs…did you “read” them? DO you know what I mean by “read your plugs” A good mechanic can tell you how a vehicle is running by reading the plugs…if they are black…or oily…or…grey…all tell a different story. So if you pulled all the plugs and read each one…the greyish plugs are running normally…the black plugs are not…and is indicative of carbon fouling which means a too rich mixture of fuel/air… Did you notice that one or more plugs looked black and or dark and oily?
The time frames you mention in your post still lead me to a leaky injector flooding a cylinder or two…
Thank you for the tip. Being that my summer commuter is a '70 Honda CB450 I’m pretty used to reading plugs. I bought the Tahoe almost two years ago and changed the plugs as part of my routine used car purchase maintenance, and remember all of them being grey. I’ll pull them again and see what they look like.
Ah…the CB450…Last one I had I bought for 200 at a yard sale…it was BEAUTIFUL…Emerald Green… 1200 miles…and CLEAN CLEAN CLEAN. I only rode it 3x bec every time I had it out people asked if they could buy it…in fact I sold it 2 wks after I bought it…bec some guys walked up while I was washing it and offered me 2200 for it on the spot… I couldnt refuse as I was broke at the time…AH how things HAVENT CHANGED…lol. I still kick myself for selling that bike…it was so nice… I should have held onto that one. I still have dreams that its in my garage and I never sold it…Damnit.
Yeah I dont know…your issue is a bit involved and I imagine its going to take a little while to suss it out. I could also be that your FPR…fuel pressure regulator is faulty…or has a faulty/leaking check valve and its not holding rail pressure?
Help me out here guys…I dont think I have many more ideas. WHATS UP?!
Circuitsmith…and all the other regular sharpshooters… Brainstorm.
When you had the intake manifold off to replace your fuel pressure regulator did you notice any evidence of fuel leaking anywhere? Was one side of the intake manifold cleaner than the other? Any fault codes or check engine light?