Bad cold starts and leaking PCV hose


New Member
Sep 23, 2018
Miami, FL
98 GT 114K miles

So yesterday I noticed that my pony was unwilling to start up when cold. The crank times was about 5 secs which way longer than usual. Starts up quickly on a warm start though.
I checked the battery and it shows 12.53 volts when the car is off.
I don't know how to check the started but I don't hear any knocking or ticking noise when cracking up the car.
I have a brand new fuel pump assembly, fuel filter and fuel pressure regulator. I have 37 PSI at idle. I also have new sparkplugs, wires and coils. The IAC is also new. No leaks in the cold air intake system.
My car hesitates when running steadily in 2nd and 3rd gears between 1,5 - 2.5 k rpm.

Today I opened the hood and noticed that my PCV hose that goes from the passenger side valve cover to the upper intake, has oil on it right where it connect to the intake (90 degree bend part. Could that cause a bad cold start and hesitation? I would assume that leakage causes unmetered air to get into the system.
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SN Certified Technician
Aug 14, 2009
Houston Texas
I have 37 PSI at idle. I also have new sparkplugs, wires and coils.
I'm assuming this is being measured with an external fuel gauge. If so, 37 PSI at idle is too high. Should be closer to 32 PSI.

With that high of a fuel pressure reading I would be concerned that the fuel pressure vacuum intake reference vacuum line is either leaking, blocked, or not connected.

Regarding the long crank time when cold. Try this. Turn the key on/pause/off several times without cranking. Does this improve starting? If so, consider fuel pressure leak down as the problem source.


New Member
Sep 23, 2018
Miami, FL

thank you for the response. It turns out that my battery is not holding the charge. Today it did not even crank. My friend jump started me and the car was running great, both, at idle and under various loads. Now I need to replace the battery. Any suggestions for a good one and yet not too expensive?
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