1997 XLT rough idle problems

[adtr223]

Hey all, got a problem that I need a little help with.

I have a 1997 Explorer XLT with the SOHC 4.0 V6. Recently the truck has been idling really rough when first started after sitting for a day. Burping the gas seems to fix it. Recently the radiator and thermostat were replaced after the radiator was rusted. (ran it like that for a few months, putting water in it everyday)

Now it runs rough at idle anywhere. When first started, stop lights, etc. And it also will stall in reverse after the first time started for the day.

I do not plan on keeping it for more than 5 months as I am moving cross country and it will not make the trek up there.

Any help would be greatly appreciated!

 

[jester1023]

There are numerous things to cause the rough idle of an Explorer. Any number of engine management components, not limited to...mass air flow (MAF) sensor, idle air control (IAC) motor/valve, coolant temp sensor, EGR valve, EGR pressure sensor, EGR solenoid...the list goes on. I found that my chronic rough idle problem was due to a weak fuel pump. A simple fuel pressure test will let you know if that's the culprit. Even a couple pounds less than the minimum will cause the problem. I now have a chronic EGR problem with my '95 Sport ohv that I have found impossible to track down.

 

[adtr223]

I had a mechanic double check the truck a few days ago to see if it could drive cross country. He said that one of the Head Gaskets is possibly cracked. Would this be causing any of this problems along side other causes?

 

[jester1023]

A blown head gasket will have other symptoms. I don't know this mechanic, but I'm very, VERY leery of mechanics that jump to the "blown head gasket" or "cracked head" conclusion with no other indicators being looked upon. For a head gasket leak to cause a change in the way the engine runs, there would be one or more indicators. Low compression in one, or two cylinders next to each other would indicate a possible blown gasket. Water getting into the cylinder...normally coupled with white steam/smoke out the tailpipe, as well as low compression. Water in the oil is a typical result of a compromised gasket or a cracked head. Excessive pressure in the cooling system or overheating is anothe indicator.

Your rough idle could also be caused by the simple need of a tune up (plugs and wires.)

 

[adtr223]

I understand, just passing along what the mechanic told my father. He is the one who did the radiator/thermostat replacement. So I assume they trust him. I do know that about two days ago the temp sensor when all the way up and it said "Check Gage" then it went back down and the light went away.

Just want a fair assessment. Will it make it 4 months with no work done to it?

 

[jester1023]

Overheating, just once absolutely can cause a blown head gasket or even a cracked head. This, of course falls into some of the criteria I listed above. If there is indeed an internal leak between the cylinder and the cooling system and you only want it to make it another 4 months, try some Bars Leak. I am not a fan of this, if you want this vehicle to be in device for anyone else in the future.

 

[adtr223]

Well then he might be right. I can name at least 3-4 times that the temp gauge was high and the truck was very hot. Usually had to pull over and put 3-4 gallons of water in it.

 

[jester1023]

Are you getting any coolant in the oil or steam out the tailpipe?