2000 Explorer 4.0 SOHC Problems

[troyexplorer2000]

Hi all,
Anyone out there having the same problems im having? I've got a 2000 Ford Explorer Sport 4.0L SOHC and whenever I start it, the RPMS will drop very low to the point where its going to stall (sometimes it does) for about 3 seconds then fixes itself and maintains a decent idle around 700-800 rpms.No check engine light. Runs and drives ok, however, the idle seems to be slightly erratic. I cleaned the MAF sensor and the IAC sensor so far. Still doing the same thing. Im thinking that the throttle position sensor may be going bad but im not sure. I plan on doing a tune up- New plugs and wires and a ignition coil. Also a new fuel filter.

Anyone have similar problems at some point? Suggestions?
TIA everyone

 

[Tyler Robinson]

Mine does this, usually on a cold start. Haven't figured it out yet, it'll stall but starts right back up no problem. Iv done a tune up and everything. Still has me confused,but when the engine warms up it's fine.

 

[koda2000]

A very common problem with the Job 1 SOHC V6 engine, which is what you have, is that the intake manifold upper and lower O-ring gaskets dry out, stiffen and shrink with age. This allows un-monitored air (air the MAF isn't seeing) to get into the engine, especially when the engine is cold (like when first started) and will cause a rough idle and stalling until the engine warms up and the parts expand. Once the engine warms up the expanded parts cause the O-rings to seal better and the engine can run normally. This condition typically is worse as the weather turns colder.

 

[Tyler Robinson]

A very common problem with the Job 1 SOHC V6 engine, which is what you have, is that the intake manifold upper and lower O-ring gaskets dry out, stiffen and shrink with age. This allows un-monitored air (air the MAF isn't seeing) to get into the engine, especially when the engine is cold (like when first started) and will cause a rough idle and stalling until the engine warms up and the parts expand. Once the engine warms up the expanded parts cause the O-rings to seal better and the engine can run normally. This condition typically is worse as the weather turns colder.

I'll have to check this out thanks

 

[J_C]

Highly doubtful it's the fuel filter given it runs at higher RPM acceptably. I'd wait on that until you have to replace the fuel pump.

Certainly it's time for wires and plugs if they haven't been done in years, I'd go ahead with that and check battery voltage, low battery without altlernator helping much at idle can cause a sluggish engine. It's not as common as some things but you're planning on doing it anyway. Coil pack I wouldn't touch until it fails.

See if it still drops RPM w/o A/C on. I had that issue and managed to fix it cleaning the IAC but some people had theirs degraded enough that it was worn beyond cleaning. On the other hand I didn't just clean mine, I put a drop of oil on the shaft and set it on end, let the oil run down into the bushing for a few hours.

 

[koda2000]

Usually when the PCM sees that the idle RPM is higher or lower than it should be it will set the CEL. Idle too high P1506 will tell you the IAC is the issue, but that's not always the cause. P0171/P0174 indicate a vacuum leak. A bad alternator can even throw a code indicating the cam position sensor is bad. Just goes to show that you can't take ODB TDC's at face value.

When our '97 SOHC started having a rough idle when the engine was cold (the colder it was out the worse it was) it would set the CEL with TDC's P0171/P0174, but only during the winter months. During the summer months it would not turn on the CEL. That was a good indication that the intake manifold gaskets/O-rings were bad.

 

[Kidd7]

Check fuel pressure also. When I was troubleshooting my stalling issues my truck was running rough. Through alot of crap, ultimately fuel pump fixed it.

 

[RandomNerd2000]

I've had this, new intake seals didn't help my case, curious what this actually is.

 

[joesjunktoo]

I had same issue, once was the o rings on the intake. 2nd one was IAC.

 

[Kidd7]

This issue was fuel pressure. I remember when I checked the last time it was a little low, within tolerance. When I open the trottle quick it could not respond fast enough and the pressure dropped to about 30 psi at some points.

 

[3xowner]

make notes on starting... does it happen when colder? no issues when say over 65'?

I had a bad fuel pump for 2 years... anything lower that say 50 degrees, it was not starting without some encouragement from a rubber mallet. between 50 and 60 it acted as you described. above 60 no real issues. It was so predictable, i let it go for 2 years in my climate. but i changed the pump/sending assembly before that next 3rd winter.

I think i actually damaged my pump myself as I was leaving the country and let my fuel level go down. I parked downhill and it did not start, maybne a few too many cranks before friends and i pushed it onto level ground to start and get over to gas station 500 ft away. After that, yes a 50'f day caused me to have a crank no start.

remember to park uphill always when lower in gas