2005 Pontiac Montana hard start when hot
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2005 Pontiac Montana hard start when hot
So my wife has been complaining about her Montana having hard starts. This seems to only happen when hot, and you park it and lets say run in to the store then come right back out. Lets hear your thoughts on what it could be. I have not had a chance to look it over, but I'm thinking fuel pressure regulator.
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It cranks just fine, just doesn't like to fire. Only seems to do it after a short time not running. If it'd parked for a few hours then no problem. I suspect the FPR is leaking gas into the vacuum line.
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Well, I got a chance to look it over the other day. And there is no FPR. Well, why would this be easy, right?
So now I'm open to ideas. This is a 2005 3.5l Montana
So now I'm open to ideas. This is a 2005 3.5l Montana
#7
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EGR issue?
IAC? Hold throttle about 2% while cranking.
IAC? Hold throttle about 2% while cranking.
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I'll have to take a peek at that. The EGR is easy enough to test. This only seems to happen after the engine is up to temp. You go to a store, shut it off, run in, buy something come out and it will crank with no start. Might take 4 times but will then start and run right. This is why I was convinced it was a bad FPR. Was looking at the listed TSB for the truck and only thing I see is harmonic balancer not seated.
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Using a fuel pressure tester, will that tell you if a FPR is going bad?
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This engine has no FPR. But to test a FPR you just pull the vacuum line and smell it. If you smell gas, it'* bad. A friend with a GP had the same exact problem with his car. Told him to pull the vacuum line, and the FPR was spraying gas. Bought a new FPR and problem was gone.