Very frustrated right now. I haven't even had the car for a month. Driving down the highway at 75mph today, the car had a sudden loss of power, and service engine soon light came on. Drove 1 mile home from where I was, total loss of power, loud knocking noise from the engine. What could it be? any guesses? I am starting to think I need a new engine. Very frustrating, after I just spend close to 1k on tires, a couple of hundred on a new radio, registration alone was 300 bucks. Not even including all of the maintenance items I bought for the next maintenance cycle. Having my dream SUV just turned into a nightmare. This is my DD, any suggestions? I have another thread in here talking about a diesel swap. I am so discouraged, I don't even know if I want to do it anymore.
Monty Just Died. I think.....
- Thread starter Fefrank
- Start date
Superduty
Adventurer
Do you think codes are a bad place to start?
Pretty simple to check. Fairly cheap to do. And you don't even get your hands dirty.
Or i guess the other option is start tearing down the engine.
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Superduty
Adventurer
Engines aren't fixed by simply looking at the codes.
Are any engine problems ever just a code thing?
The codes are just a place to start. A place that might give you some direction.
If it tells you your timing is off then you might start looking at the belt or chain.
If it tells you there is a problem in cylinder 3, then you have a clue the mechanical problem might be there.
If it tells you your engine oil is low, then that's a clue as well.
It takes 10 minutes max to pull the codes. It's where i would start.
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Are any engine problems ever just a code thing?
The codes are just a place to start. A place that might give you some direction.
If it tells you your timing is off then you might start looking at the belt or chain.
If it tells you there is a problem in cylinder 3, then you have a clue the mechanical problem might be there.
If it tells you your engine oil is low, then that's a clue as well.
It takes 10 minutes max to pull the codes. It's where i would start.
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Thanks for all of the information. its a 3rd gen monty with the 3.8 v6. I will check the things you mentioned in the morning, and let you know. The engine still runs, it drove me about a mile from when it started the commotion. Oil is filled, and as a matter of fact, it was just changed last week. It is currently not leaking any oil, and the oil looks clean. The Montero has 184,000 miles and timing belt was replaced at 167,000 according to service records, of being replaced at 60k intervals before that by a local shop. I am the second owner of this car, and the car was thoroughly maintained, with service records in-hand to prove it. I'll keep you posted.
Superduty
Adventurer
nwoods
Expedition Leader
I am not personally knowledgeable about this, but i’ve heard the 2003 and later 3rd Gen’s can injest the screws that’s operate the intake butterfly valves. That kinda sounds like what happened. I suspect this would result in bent valves, which is a pretty major repair, but if you tear it down your self and send the heads out, will cost about $250 per head.
Before you do that, you’ll want to do a cylinder compression test and probably a leak down test. Those tests will tell you what happened and what you need to fix.
Before you do that, you’ll want to do a cylinder compression test and probably a leak down test. Those tests will tell you what happened and what you need to fix.
Swift_45a
Observer
Why did you prolong the maintenance stuff before the tires/audio stuff? These trucks are often super neglected from thier previous owners, and are why we often get them for such a good price compared to Landcruisers and such. I mean I went a while not changing the oil on the SR when I bought it as it wasn't my daily driver, maybe a few weeks/months, but once I took it out with my stuff in it, I made sure all the fluids were flushed and such as it had 165k on the engine.
Phone audio is pretty lossy, but that sounds like rod knock to me, which would explain the sudden loss of power; pdd that it would happen without overheating or something else.
I'd do what shovel said, I don't know anything about non-6G74s, but I'd start considering a rebuild in the near future.
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With all due respect Swift_45a. It sounds like you didn't read the comments above with the exception of my initial comment. I have service records from the previous owner, stamped by a competent local shop who did all of the maintenance religiously on this vehicle since new in 2005, 3,567 miles old to be exact. The car has been very well taken care of. The reason why I got it for such a good price, is because this family was moving out of state, and had already bought a 3rd vehicle. I did not prolong any maintenance, absolutely nothing was due to be changed other than the oil, which was done by me last week, 100 miles before its due date. All the fluids were full and as a matter of fact the next service schedule for this vehicle by the local shop, was at 192,000 miles. which included spark plugs, serpentine belt, air filter, and the next oil change. The timing belt was replaced with all of its components, at 167k with the local shop confirming this after I called them to talk about the records.
It doesn't sound like a timing belt problem, nor a bottom end problem. The frequency of the tapping noise makes me think valve train, possibly a collapsed lifter, although a dead lifter wouldn't usually create a significant loss of power. Maybe more likely is a butterfly plate from the variable intake system - the bushings supporting the butterfly shaft wear out allowing the shaft to vibrate, which ultimately works loose the screws holding the butterfly plates to the shaft. Eventually the butterfly falls into the engine and can bend valves and damage pistons.
I would start by pulling the plugs and check for anything unusual, followed by a compression check to see if there's any internal engine damage.
The attached photo is from my 3.5 DOHC showing the actuator and butterfly shaft - being that yours is a 3.8 the details might differ but the design should essentially be the same. Check the shaft for play and movement, if it's loose and sloppy then it needs repair or replacement
I would start by pulling the plugs and check for anything unusual, followed by a compression check to see if there's any internal engine damage.
The attached photo is from my 3.5 DOHC showing the actuator and butterfly shaft - being that yours is a 3.8 the details might differ but the design should essentially be the same. Check the shaft for play and movement, if it's loose and sloppy then it needs repair or replacement
Attachments
DSouth
Observer
I agree with RyanY's post. On my 2003 Limited one of the spark plug ground electrodes broke off. It sounded quite terrible, and threw all kinds of codes and died on the freeway. Eventually, after replacing the plug and letting the engine idle for a bit the noise went away and it's been running fine ever since. YMMV.
Thank you all for your replies. I will work on it this week, and keep you posted. I have also found a motor for about $1500 with 112k miles on it. So if it comes out to that, I kinda have it covered, though It will suck to pay for freight. So I do hope is one of the simple fixes mentioned previously. Question, wouldn't anything falling into a cylinder bore mess the walls up? That means I would need a new engine doesn't it?