We're at the end our our sanity in trying to diagnose what's up with our 2001 Discovery II. 71,000 miles. Over the last year or so, it has occasionally overheated and we immediately stopped and topped off with coolant. It would sometimes go several month with no problem at all, then overheat a few times in short order. We took it in and water was found in the oil. There were 16 codes that pulled at the time (p0171, p0174, p1175, p0733, p0734, p0732, p0171, p0174, p1175, p0305, p1415, p1300. p1172, p1319, p0302). Here is what has been done:

Oil pan removed/engine cleaned
Leak found in timing cover from pressure test--replaced timing cover
oil change/new filter
replaced water pump, drive belt, tensioner, pulleys (recommended since they were in there and there'd be no labor charge to do it)

Computer was reset, but "Service Engine" light came on after about 40 miles. Lost coolant from radiator, again. Took it back and they did the following:

head gasket replaced,
both banks(B) replaced
Valve job, cylinder head bolts replced
Machine work: pressurized head, resurface head, grind valves, replace valve seals.
Replaced thermostat.

Computer reset and test driven. After 60 miles, engine light came back on and codes pulled: p0305 (#5 cylinder) and p0174 (System lean, bk 2)

Mechanic threw in the towel and now says we need a new engine block and suspects a dropped cylinder sleeve on #5.

Any input??? There's been so much done to the car, we don't want to make a hasty decision if it's possible that the codes could be caused by something less catastrophic.

THANKS!

 

There are other things that can make a misfire condition, and there are several things that can make a system lean code. Are you still having loss of coolant, gurgle under dash, white exhaust smoke, overheating?

When you list both bank (B) replaced, what does that mean?

A slipped sleeve can cause the annoying tick, allow coolant to erroded a crack behind the liner, all sorts of fun things. But it could be something they would have seen with heads off (?) As for the misfire code and the 0174 code, that is more fuel delivery than overheating. 0174 happens when a calculated value is more than about 23% out of expected range involving engine speed, engine load, and airflow. It won't show up until it tests bad in two drive cycles, so it may have been there at the shop as well, you might not have driven the whole 60 miles on one trip.

There is an engine block pressure test that can be performed to verify block integrity. This is different from a coolant pressure test, and more expesnive to perform.

Without more overheating, or coolant leaks, you may be on something more like plug and wires, etc.

How much have you invested in these repairs so far?

 

First, thanks for your input!

THe "both bank (B)" is a mystery to me (as are most things engine related)--I took it off the mechanics notes. I can scan and email the printouts from the mech, if that would be helpful. It appears to be part of the head gasket replacement?

Have only driven it about 140 miles since we last picked it up. No "slushing" sound under the dash, which we did experience before the work was done and no detectable coolant loss, so far. No overheating, either. Thermometer is right in the middle of the gauge. There is whitish smoke when I first kick it over in the morning and lasts for less than a minute. No smoking while driving or idling after that first minute.

When the #5 cylinder code popped up again after the initial work was done, the mech told me he replaced the spark plug and wire, so that has been done at least once (twice, I think).

The first round of repairs (liner replacement, pulleys, tensioner, water pump etc. was $1888 and the second round (head gasket, machining etc) was $2000, but the mechanic didn't charge us.

 

Forgot to mention that the mech didn't really diagnose a slipped sleeve. I think he was just at wits end to diagnose the problem and was guessing that could be it. He seemed a bit surprised, since he said the visual after the machining was done looked perfect.

 

I am encourgaed that overheating has subsided. The gauge being in the middle is an average decision of the engine computer, a scanner can be plugged in and monitored while driving to show "true" raw temperature data. There will be some up and down, but should not have dramatic spikes above 212 F. Others may join in, but I would think that Murphy's Law is not done with you yet, and this may be related to a fuel or ignition problem. Sorry, I have never just replaced one wire, usually the whole set is starting to break down. But perhaps more codes will be generated and guide you.

 

Thanks! Believe me, my eyes have been glued to the temp gauge. Maybe a new set of eyes will locate the problem. Any recommendations for someone in the san francisco bay area?

 

Some one will chime in on that reference, and look at this post, which shows a type of monitoring gauge you might be interested in, with photos under real world conditions. Does temp, mpg, and other things. https://landroverforums.com/forum/di...estions-44888/

 

Read my reply on the LRO, then lets talk.

 

Just checked coolant level and it appears to be losing fluid. it has been two weeks since we got it back and it was to the fill line. Checked last week and it seemed to still be full. Today it is lower.

 

When are you checking it, stone cold or warm, have you bled the system, do you have noise in the dash, water fall sounds?