Hard start when cold?
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I've been having this problem when my car has been sitting for at least a couple of hours. Such as overnight in the garage or it was really bad last night after sitting outside all night at my girlfriends.
The car is crazy hard to start. It cranks and cranks and will occasionally hiccup a bit out the exhaust. The crank time has been increasing over the last week or so. It eventually starts though. Once it has it seems to run and drive fine. Gas mileage is the same. At idle I occasionally get an extra burble through the exhaust but the idle seems consistent. My tach isn't correct so I'm not exactly sure what the idle is at. I think around the factory tahoe ~600rpm. I get no CEL but I have no scanner to get the actual sensor outputs. I hear the fuel pump priming when I switch to key-on. Ideas?
The car is crazy hard to start. It cranks and cranks and will occasionally hiccup a bit out the exhaust. The crank time has been increasing over the last week or so. It eventually starts though. Once it has it seems to run and drive fine. Gas mileage is the same. At idle I occasionally get an extra burble through the exhaust but the idle seems consistent. My tach isn't correct so I'm not exactly sure what the idle is at. I think around the factory tahoe ~600rpm. I get no CEL but I have no scanner to get the actual sensor outputs. I hear the fuel pump priming when I switch to key-on. Ideas?
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Could be the check valve in the pump.Put a fuel pressure gauge on it after it sets and check your fuel pressure.Or cycle the key 5 or 6 times before you try to start it. If it starts right up the pump is bad.
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I tried cycling the key five or six times this morning and it actually took the longest yet. I think that's more because the problem is getting worse though. I'll have to get my pressure gauge back from a friend before I can check it for sure though. The pump is a "newer" walbro, installed ~05 or so.
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If your fuel filter is clogged or partially clogged you will have a hard time starting even if you have fuel injection.
Ask me how I know, had a friend w/ a fuel filter partially clogged w/ 85K miles and sometimes it would take me 2 or 3 cranks. Even with fuel injection fuel drains the system does not stay primed specially after a long stand (ie overnight)
Ask me how I know, had a friend w/ a fuel filter partially clogged w/ 85K miles and sometimes it would take me 2 or 3 cranks. Even with fuel injection fuel drains the system does not stay primed specially after a long stand (ie overnight)
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The filter is less than a year old. ACDelco version of the C5 filter/regulator asm.
I tried cycling the key five or six times this morning and it actually took the longest yet. I think that's more because the problem is getting worse though. I'll have to get my pressure gauge back from a friend before I can check it for sure though. The pump is a "newer" walbro, installed ~05 or so.
I tried cycling the key five or six times this morning and it actually took the longest yet. I think that's more because the problem is getting worse though. I'll have to get my pressure gauge back from a friend before I can check it for sure though. The pump is a "newer" walbro, installed ~05 or so.
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Hate to break this to you but the supply line is never drained if it is the check valve is bad in the pump. The prime cycle when you turn the key on is to get pressure against the injectors. Fuel filter issues cause poor fuel mileage with extended cranks and sometimes lean codes. Not "It cranks and cranks and will occasionally hiccup a bit out the exhaust". Now ask me how I know this Because I do this **** for a living not a ****** internet hobby.
Last edited by BaddBird; 07-05-2010 at 05:38 PM.
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I finally got around to checking the pressure since the schrader valve was broken I had to extract that. KOEO; ~55psi. During cranking I get ~60psi. Crap. Any ideas?
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