Can't figure it out - Cooling issues..

[EXP Edition]

1998 Expedition XLT.

Just purchased the truck last week. My heater was kind of intermittent.. It would sometimes blow cold and sometimes hot. When it would blow hot air, the temp gauge on my dash would be right where it was supposed to be, about half way. When it would blow cold, the temp gauge would be ice cold.

I changed the thermostat and that seemed to help a little bit as it would blow hotter for a little longer.

My coolant looks really really rusty. Orange but non-transparent.

Also, a cold start is tough on the truck. It would idle very low and almost misfire a little bit until it smoothened out after about 10 seconds. But, for that first 10 seconds, it would blow alot of white smoke from the exhaust and it smelled like coolant.

Never had an overheating issue with the truck so far, except for this morning. All of a sudden I was overheating and my low coolant light/oil light came on. I pulled over, turned the truck off and opened the coolant reservoir cap. I relieved the pressure and waited for the smoke to quit coming out of the reservoir, and it was practically bone dry.

Started the truck up, perfect. Temp gauge right in the middle, and I drove it to work with no problems.

I'm thinking intake manifold gasket?

I was going to do a coolant flush this week to clean out the system because I suspected my heater core was getting a little bit plugged.

I'm hoping its not a head gasket. I have 2 other cars of my own that need them. This doesn't really have the symptoms of a blown head gasket, however.

My only other thought is that it does have a blown head gasket, and the people I bought it from block sealed it for a cheap fix. This could possibly explain the rusty coolant along with intermittent bursts of shit.

Any ideas? I just bought a Haynes manual last night but I left it at home, I'm at work now.

 

[KWT2000]

Hi are you getting a check engine light or trouble codes??? the hard start could be an intake leak or a dirty IAC... poor heat could be a plugged cooling system as well as the over heating issue... if it is a head gasket you should see some evidence on the dipstick or oil cap or coolant resivor... im thinking the intake leaking would be visable with a pressure check... keep us informed

 

[EXP Edition]

Did a coolant flush yesterday and it helped GREATLY. I almost had to roll the windows down to let some heat out of the cabin it was so hot.

But, under heavy accel or even moderate accel, my air blows cold, and then back to hot under cruising speeds.

Driving to work today I developed a mild misfire. No cel but at idle and driving you could feel it. I scanned it anyways and came up P0174, P0171, P0401, P0302 and P0133.

P0174 and P0171 are "system too lean" codes, which the 174 is bank 2, 171 is bank 1.
P0401 is Exhaust Gas Recirculation Flow Insufficient Detected
P0302 is Cylinder 2 Misfire
and P0133 is 02 Circuit Slow Response (Bank 1, Sensor 1)

I always had a decent vibration on the highway when giving the truck a little bit of gas, too. When I let off the gas, the vibration goes away.

I'm now thinking heavily on the idea of a leaky intake manifold gasket.

 

[KWT2000]

the po171 and po174 very common with the triton motor check out the how section for those two codes try cleaning the MAF sensor and the IAC and check the PCV line from the valve to the intake... since you recently bought the truck manit. may have not been done as for the po302 possibly bad coil or plug... the po133 slow reacting o2 sensor... the only fix i know of for that is to replace it... and the po401 since it over heated ive seen that damage the diphram in the egr valve... let us know what you find

 

[EXP Edition]

I cleaned the MAF when I first bought it because it was kinda doggy on the acceleration. That helped.

It runs fine with full power until it warms up now. Then it starts missin'.

I popped the coolant reservoir and it kind of smells like gasoline now... Cracked head? Hope not.

 

[KWT2000]

I cleaned the MAF when I first bought it because it was kinda doggy on the acceleration. That helped.

It runs fine with full power until it warms up now. Then it starts missin'.

I popped the coolant reservoir and it kind of smells like gasoline now... Cracked head? Hope not.

it is very possible head or head gasket... i think i would pay to have the headgasket test done then you know what your up against

 

[EXP Edition]

My mechanic and I did a pressure/leakdown test and pressure stayed right where it's supposed to be.. Never lost pressure.

I found my PCV hose on the passenger side had a hole in it. We put a new hose in it and it still misfires but now only have 3 codes:

System too lean (Bank 2) instead of both banks
Misfire Cylinder 2
Lack of Heater o2 sensor switches indicates system too lean.

 

[KWT2000]

did you do the chemical exhaust presence test???

 

[EXP Edition]

Not yet, was going to do that this week, however.

Fixed the miss, I replaced the plug on Cylinder 2 and it runs fine again. The plug itself looked brand new almost, but had some oil on it. As well as the plug wire.

I didn't check the rest of the plugs/wires since I was kind of in a pinch, but I will see if they are similar tomorrow.

 

[grantikal]

where are the so cal codes displayed? on the dash or do you have to have those whatchamacallits plugged in to see them?
sorry, i am new to all this