'99 4.0 OHV "hard" starting...?

[35Remmy]

When cold (30's and below) I'm getting about 5 or 6 cranks out of the engine before she starts...and when she does, I'm getting a "chugging" idle for maybe 20 seconds. After it has warmed up, 1 crank and it starts. Then runs like new.

My upper intake manifold gaskets have maybe 10,000 miles on them. I have 95,000 miles total.

 

[cjones101812]

you should check the IAT (intake air temp) sensor. Ohms reading should be 58.75K (58,750) ohms at 50*F. 37.30K at 68*F. should be higher the colder it is. the lowest temp reading my the chart shows is 50*F

so if 30*F outside before startup then the Ohms reading should be much higher than 58.75K

 

[35Remmy]

CJ...good idea, I don't know how I didn't think about the IAC...Mine was mooing quite frequently a while back...I cleaned it out and the noise stopped, so I left it alone. Thanks for the Ohms readings, I'll be sure to check those out.

 

[35Remmy]

oops...I meant IAT sensor. Different, right?

 

[cjones101812]

oops...I meant IAT sensor. Different, right?

yep, different.

IAT - intake air temp

IAC - idle air control

 

[35Remmy]

OK, so I checked resistance and everything seems OK...resistance drops when warmer, increases with cold...it's about 30 right now and resistance is around 87.

 

[N84Christ]

egr woes

I am trying to remove the egr valve on a 99explorer 4.0. Can some one tell how to get the threaded flange piece out of the egr valve. Getting frustrated and skin transplate (Just joking )Anyhelp would be great

 

[35Remmy]

N84...my '99 4.0 OHV doesn't have an EGR valve...but are you talking about the EGR tube?

If so, don't get excited as they are typically really hard to get out.

My brother sprayed his with PB Blaster for a whole day, and it finally came out without breaking it...they do break fairly easily.

 

[cjones101812]

OK, so I checked resistance and everything seems OK...resistance drops when warmer, increases with cold...it's about 30 right now and resistance is around 87.

if that's 87,000 Ohms then that is good.

check for codes.

 

[cjones101812]

N84...my '99 4.0 OHV doesn't have an EGR valve...but are you talking about the EGR tube?

If so, don't get excited as they are typically really hard to get out.

My brother sprayed his with PB Blaster for a whole day, and it finally came out without breaking it...they do break fairly easily.

unless you removed the EGR valve it should have one.

 

[35Remmy]

CJ...believe it or not, the '99 4.0 OHV is EGRless. I thought the original owner removed it too...if you look at my upper intake manifold, the casting holes for the EGR system are there, but came "plugged" from the factory...well, not "plugged", but casted so they are unusable.

 

[cjones101812]

CJ...believe it or not, the '99 4.0 OHV is EGRless. I thought the original owner removed it too...if you look at my upper intake manifold, the casting holes for the EGR system are there, but came "plugged" from the factory...well, not "plugged", but casted so they are unusable.

you're right, some 99 rangers do not have an EGR valve but the ones that do have it near the oil dipstick not on the intake manifold according to my ford manuals. VIN code "X" OHV.

 

[35Remmy]

CJ...I've always wondered "why"?

 

[N84Christ]

N84...my '99 4.0 OHV doesn't have an EGR valve...but are you talking about the EGR tube?

If so, don't get excited as they are typically really hard to get out.

My brother sprayed his with PB Blaster for a whole day, and it finally came out without breaking it...they do break fairly easily.

Thanks for the reply. I purchased the egr valve that has a bolt that has a tube that goes thru it. I can not get that bolt out. I applied heat and PB Blaster.
I have replaced the plugs and wires and the coil pack and the downstream O2 sensor but I can not get the idle to smooth down. Running down the road the truck runs smooth. The parts people told me the egr valve should be replaced. I can not afford to leave it at a mechanic while he keeeps try by process of elemination. Any help would be great.

 

[35Remmy]

N84...were you getting a code for the EGR valve?

Be careful, a LOT of times when you get a code for the EGR valve, it's actually your DPFE sensor that monitors the EGR valve (Delta Pressure Feedback... something).

So you're getting a rough idle?

 

[N84Christ]

N84...were you getting a code for the EGR valve?

Be careful, a LOT of times when you get a code for the EGR valve, it's actually your DPFE sensor that monitors the EGR valve (Delta Pressure Feedback... something).

So you're getting a rough idle?

Yes when the computer at advanced auto check the "check engine light" it said there was a delay in the downstream o2 sensor and an error at the egr valve. I replaced the o2 sensor and was trying to replace the valve with no avail ( aplied heat and 5 lb. sledge ) Is there a way to check the dpfe sensor?

 

[96eb96]

Yes when the computer at advanced auto check the "check engine light" it said there was a delay in the downstream o2 sensor and an error at the egr valve. I replaced the o2 sensor and was trying to replace the valve with no avail ( aplied heat and 5 lb. sledge ) Is there a way to check the dpfe sensor?

Yes, one wire should have 5V, another 0 volts, and a third .5 or 1 volt at idle AND when the key is in run but the engine is off. If the third wire deviates more than .1V from .5V or 1V at idle replace the DPFE, nothing further to test.

 

[N84Christ]

Yes, one wire should have 5V, another 0 volts, and a third .5 or 1 volt at idle AND when the key is in run but the engine is off. If the third wire deviates more than .1V from .5V or 1V at idle replace the DPFE, nothing further to test.

Thanks we just got a dumpload of snow so I will check it out in a day and get back. Thanks for your time and God Bless.