1997 Ford Explorer codes

1997 FORD EXPLORER
194,000 MILES • 6 CYL • 4WD • AUTOMATIC
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MARCUS9415
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codes p0171 and p0174 i have fixed upper and lower intake manifold gasket change out plugs and plug wires and the two upstream 02 sensors and the pcv and cleand the mass air flow sensor and and changed out fuel fuel filter and codes still come back
Jul 16, 2010 at 12:16 PM
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JACOBANDNICKOLAS
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Based on the codes and the work you have already done, I think you are looking for a vacuum leak. Have you thoroughly for that?
Jul 19, 2010 at 10:50 PM
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MARCUS9415
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how would i check for a vacuum leak on a 1997 ford explorer 4.0L S.O.H.C
Jul 23, 2010 at 12:04 PM
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JACOBANDNICKOLAS
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First, I recommend a visual inspection. Check for damaged, dry rotted, or disconnected hoses. If you have no luck, many mechanics (not me) will start the engine and spray carb cleaner or starting fluid on the hoses. If there is a leak, the RPM's will increase.

I don't like doing it that way because of the risk of fire. If you do it, just have a fire extinguisher near by incase something happens. Make sure it is one that will put out an oil / grease fire.
Jul 24, 2010 at 12:58 AM
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MARCUS9415
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ok i will check it tomorrow and let you know what i find and thank you
Jul 24, 2010 at 1:48 AM
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JACOBANDNICKOLAS
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I don't mean to scare you with the fire issue, but it can happen if the spray hits a spot that is hot enough.

be careful.

Joe
Jul 24, 2010 at 9:59 PM
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MARCUS9415
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i went over all the vacuum hose i seen and i could not find a leak


marcus
Jul 25, 2010 at 8:56 AM
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FIRESTORM
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When you replaced the intake manifold gaskets, did you make sure that the intake seated good? Did you happen to apply some rtv sealant around the bolt holes to make sure it would seal around said bolt holes? Lastly, did you torque the bolts to specs? Following torquing order, get each one close to torque spec, then move to the next one, then next, etc. Then come back to the first one and actually torque?

It sounds like you're still having a leak around the intake.
Jul 25, 2010 at 7:19 PM
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MARCUS9415
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hey sorry it took me so long to get back to you but i fixed the intake but now its hard to start 1997 ford explorer 4.0l s.o.h.c hard to start time to time i can go out and starts just fine then turn it off and 10mins later try to start it again and it will not start then about 45mins later it starts right up and runs great any help would be great thanks
Sep 22, 2010 at 10:20 AM
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JACOBANDNICKOLAS
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I had a feeling it was vacuum related. Glad you got it fixed.

As far as the no start, first, check to see if there is spark and fuel to the engine when it refuses to start. Also, there is and "EEC Relay" in the relay block under the hood. When it doesn't start, switch it with another relay with the same part number to see if it will start.

Let me know what you find.

Joe
Sep 23, 2010 at 8:42 PM
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MARCUS9415
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i have spark and there is fuel getting to the rail but i looked in the ford owners guide at the relays and it dont say anything about the eec relay
Sep 24, 2010 at 1:45 PM
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JACOBANDNICKOLAS
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First, sorry about the delay in getting back to you. I lost my father this week and things have been...

As far as the spark and fuel, is it a hot snapping blue spark? Is the fuel pressure within specs? Finally, have you checked to see if the injectors are getting power?
Sep 25, 2010 at 12:45 AM
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MARCUS9415
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hey man im so sorry to hear about your dad and i hope family is doing ok


the fuel is about 30-40 and the good strong blue spark


but i will have to look at the injectors on monday and i will let you know something then
Sep 25, 2010 at 9:24 AM
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JACOBANDNICKOLAS
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Thanks.

As far as the no start, if you have good spark and fuel pressure to the rail, the fuel can't be getting into the engine. Thus, the injectors have to be the problem. Will it start with starting fluid for a few seconds?
Sep 26, 2010 at 1:21 AM
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MARCUS9415
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it will start but it takes me like 10mins to get it to start but when it starts it runs great
Sep 26, 2010 at 11:58 AM
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JACOBANDNICKOLAS
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Then it is one of three things (I realize you checked some). Low fuel pressure, temp sensor, weak spark, low compression, or no injector pulse.
Sep 27, 2010 at 12:19 PM