Hard Start

[97Pathfunder]

Hey guys,
Alright heres the issue. 1997 Path 4wd v6, cranks just fine, but for a long time, and sometimes i have to do a full throttle start. Once it starts it stumbles a little bit and then smooths out. Sometimes have to feather the throttle to keep it from falling on its face. Also, after driving around, if i stop and shut it off and try to restart, it acts as though its hydrolocked. and then i sit for a few minutes and it turns over just fine. The first issue im thinking maybe a leaking fuel regulator or IAC.

oh btw it has 194000 on the ticker

[Hooligan]

It could be a number of things. You don't mention if there has been a tune-up recently. Are the spark plugs new? Do you get a puff of smoke when it finally fires? The hydrolock that you mention could be that the ignition timing is too advanced. Has your timing been checked? What kind of millage are you getting? Has the motor been worked on recently? Do you go to church regularly?

[97Pathfunder]

Ok,
so I got the service history from my Father-in law. The truck just clicked 194000 last night. About 38k miles ago it had the timing belt, plugs, wires, cap and rotor, fuel injection system cleaned. Theres no puff of smoke after it fires.

[smj999smj]

Well, if they are using standard copper plugs, they would be overdue by 8000 miles. If they are platinum, they should be okay. I would pull one and check and also make sure they are NGK's.

It could be one or more fuel injectors leaking down; I would test the fuel pressure with a gauge and then do a fuel pressure leakdown test.

It could also be an IAC/AAC valve issue....be it a faulty or dirty valve or circuit issue.

I would also check for play in the distributor shaft, as this seems to be a common problem on VG engines lately.

[97Pathfunder]

I was thinking IAC because it seems if I do a full throttle start it fires right up

[smj999smj]

Possible...but it may be starting at full throttle because it's flooded (ie leaking injectors). Only way to know is to do some testing.

[97Pathfunder]

Could it be possible leaking injectors could cause the "hydrolock" complaint i spoke of as well?

[Hooligan]

Then you would likely see that puff of smoke.

[slopoke]

Check fuse #26 which is a 7.5 amp fuse. This circuit only gets power while cranking over from the Ignition switch. The purpose of this circuit is to inform the PCM that the starter has been requested to operate, and that the engine is cranking over and to configure the fuel and timing maps for starting. If this fuse is blown or the ignition switch is bad,the PCM loses this reference and does not know the starter has been engaged resulting in hard/long start. This would also make sense with it being more likely to bust off and run with the throttle wide open because engine speed increases slightly just above normal cranking RPM of 250rpm at which point the PCM will recognize a spinning engine and give you spark and fuel. I have run into this more than once as an auto technician. check this first! otherwise monitor the spark and fuel injector pulse and fuel pressure while cranking and see what you are missing. best of luck