Here's my problem with my 2003 Ram 1500 4.7L 4x4 112,000 miles. I purchased the truck brand new so I know it has been maintained to the T. It started 8 months ago @ 100,000 miles and every couple weeks something new would pop up.
1. Rough idle, Loss of power and fuel mileage in the crapper No codes. Cleaned fuel system and throttle body with seafoam, Replaced TPS, IAC, MAP. checked for Vac leaks none found. Power returned and idle cleaned up. Mileage another story.
2. Blew a lower radiator hose. Replaced hose and Cap
3. Misfire Cyl 8. P0308 -Replaced the Ing Coil and and all 8 plugs due to heavy wear.
4. Losing coolant with no visible leak. No coolant in oil. Oil change, cooling system flush with new thermostat.....still losing coolant heavy steam from exhaust at start up.
5. Audible tapping at start up that would go away once the motor warmed up. Thought it might be a rocker tapping so I used some marvels mystery oil with oil change. Didn't help, Researched and found it could be exhaust manifold leak. Could find any broken or loose bolts or signs of blown gasket.
6. Last week I had codes P0442 P0300 P0306 severe loss of power, a continuous tap (more of a thud now) that doesn't go away. Replaced gas cap fixed evap code, replaced cyl 6 coil fixed P0306. Then I still got P0300 and now P0172. I replaced the other 6 coils and pulled all the plugs and found Cyl 1 was wet with fuel. Cleaned plug that fixed the P0300 but the P0172 Bank 1 rich code kept coming up. Checked injectors all Ohm at around 13.

So here is where I'm at. Truck is running like crap, Severe lose of power with noticeable misfire going up hills or pulling a load, engine stumbles at 1500 to 2000 rpms and trans is not shifting due to this, Still losing coolant. P0172 still poping up. No other codes.
So do I have a blown head or intake manifold gasket? My next step is compression test, fuel pressure test and pull the valve covers to see if I have a fallen rocker arm. After this I'm at a lose. If I do have a blown gasket why am I getting a P0172 code? Any help or ideas would be awesome.

 

How old is the battery?


SJ03

 

4 months old

 

When you did your plugs, did you unplug your battery? If not, unplug the battery for a couple of minutes and touch the + and - together for about a minute. This will reset the computer.


SJ03

 

Every time I replaced a major component I reset the PCM. I'm wondering if I have a bad O2 sensor and thats where the P0172 is coming from. But I'm pretty sure Ive got a blown head gasket with the lose of coolant.

 

You can do a block test. Or a compression check. Very well could be head gasket.

 

Fuel pressure check was good but compression check on cylinder 1 was bad. Pulled the Valve cover and found a rocker had fallen. I replaced the Lash adjuster and reinstalled the rocker arm. Buttoned everything up and running pretty smooth. But I found another exhaust leak so I'' have to pull the manifold and replaced the gasket.