Engine Failure Due to Spark Plug Implosion

[finallyacura]

I just had an engine failure on my 2005 MDX with 87,000 miles. The engine light came on when the car started shaking violently. I stopped and had it towed to the dealer where they gave me the bad news -$12,000 for a new engine! After looking through the posts on this forum, it seems to me that Acura has an engine failure problem quite often. Has anyone had success dealing with Acura customer service regarding financial assistance since an engine with 87000 miles and regular maintenance shouldn't blow up!! Also, I found an used 2003 MDX engine (with 47000 miles and a compression of 200) and was wondering if that would work in my 2005 MDX? Thanks for reading this!

[PsychoKnight]

For the original poster 15mo ago, to say that there is no compression in a cylinder doesn't mean it requires a new engine - the problem isn't with the piston or rings, but the valve, valve guide, and valve seating surfaces. Just needs a head job, recutting the seats, replacing any bent valves and cracked guides. Head will be chemically tanked for down-to-the-metal cleaning and mating surface will be re-decked for flatness. Except for the head gasket, all the parts fit into a sandwiche ziplock. I had 1/2 my valves and guides replaced - $2,400 for both heads.
Still a far cry from replacing the engine.

[G. COLTON]

Originally Posted by gallen

We have a 2005 MDX with 175K miles and an excellent maintenance record. Check engine light came on and codes pointed to valve adjustment. When the mechanic started the job, he noticed one of the spark plugs had been crushed and part of it went down into the cylinder. A machinist was able to get it out without the heads coming off but now there is no compression in that cyclinder. It is blowing by the piston and rings. The Acura dealer says they can give $1000 if I buy a new car or if I replace the engine for $14,000. Otherwise a used engine could be put in for about $5,000. Has anyone ever heard of this failure? Any ideas about the best way to approach this problem?

An engine that has eaten a spark plug is not all that rare. A well known failure.

The mechanic that originally looked at the engine should have told you that it was most likely that a rebuild would be necessary.

Does nobody ever work on an engine these days? Is replacement all they do? $5000 seems high to me for an automobile engine. About right for a boat engine including replacement.

If the vehicle is driveable take it to another mechanic. Otherwise talk to other mechanics about rebuilding the engine.

George

[PsychoKnight]

Originally Posted by G. COLTON

An engine that has eaten a spark plug is not all that rare. A well known failure.

The mechanic that originally looked at the engine should have told you that it was most likely that a rebuild would be necessary.

Does nobody ever work on an engine these days? Is replacement all they do? $5000 seems high to me for an automobile engine. About right for a boat engine including replacement.

If the vehicle is driveable take it to another mechanic. Otherwise talk to other mechanics about rebuilding the engine.

George

I think it depends on the complexity of the engine - higher tech engines seem to have about twice as many sensors, valves, and harnesses as a similar engine 12 years ago. On my brother's 12 cyl Mercedes, it cost nearly $4000 just to replace the engine harness; they had to dissassemble the entire dash, many firewall componenets, and 1/3 of the engine componenets. No mechanical work was done. It would have been $6500 if he had it done at the dealer.
For Japanese cars, nobody rebuilds the engine. Not when Japan requires engine replacement at 50k km. They ship all these 30,000mile engines to the U.S. and there's a always a huge inventory available for engine replacements. Of the $5,000, about $2,200-2,400 is labor only to pull & and replace the engine. It would cost more than a used engine to rebuild a 24 or 32 valve engine, reboring for oversized rings, etc. The rebuild kit itself is over $1,000, plus the machining costs, and regular mechanic work stripping and reattaching all the exterior components. Modern engines last at least 200k mi, so in all cases, its more feasible to find a low-mileage replacement core.

[Joeroader]

On 2005 Acura MDX the No. 4 cylinder failed. Smoke/fumes and the smell of burnt rubber was apparent from the V6 engine cylinder area. The MDX had about 75,500 mi. on it. While driving the engine vibrated (felt shutter) and performance was erratic. Engine light and VTM-4 stayed on until engine could not be re-started. Had to have MDX towed to dealer. Apparently the spark plug failed and part of it ended up in the cylinder causing significant engine damage. On internet, others had noted a similar problem with the no. 4 cylinder. What could of caused this problem? Could there be a quality control problem with the engine head tolerances (such as plug threads)? Note the MDX had the original DENSO plugs and they never have been re-installed or replaced. Now dealing with a major engine overhaul or replacement.

[Joeroader]

Originally Posted by Joeroader

On 2005 Acura MDX the No. 4 cylinder failed. Smoke/fumes and the smell of burnt rubber was apparent from the V6 engine cylinder area. The MDX had about 75,500 mi. on it. While driving the engine vibrated (felt shudder) and performance was erratic. Engine light and VTM-4 stayed on until engine could not be re-started. Had to have MDX towed to dealer. Apparently the spark plug failed and part of it ended up in the cylinder causing significant engine damage. On internet, others had noted a similar problem with the no. 4 cylinder. What could of caused this problem? Could there be a quality control problem with the engine head tolerances (such as plug threads)? Note the MDX had the original DENSO plugs and they never have been re-installed or replaced. Now dealing with a major engine overhaul or replacement.

Upon further inspection, engine head dome for cyl. # 4 was severly pitted.

[JDH-MDX]

Similar situation initially, however a very different situation now.

2003 MDX 135K, Plugs were replaced at 90K by the previous owner at a local shop (that I dislike) so they were likely low end plugs.

Middle front cylinder (what number would that be? 4 I'm guessing! )

Check engine light came on and reset after third re-start a couple times. The last time it came on I was driving to a friends house to "pull the codes." Then it started running really rough and there was smoke from under the hood. Shut it off and had it toed.

Mechanic (Great guy - Honda trained but dealer adverse) investigated and said that the coil pack melted the plug and the only option he had to get it running to see if there was anything else wrong was to drill it out. Now I'm running with some kind of "sleeve" that adapts the larger drill hole to the size of the plug thread.

Think I can trust this sort of repair? What would you do at this point? What do you estimate replacing the head would be?

Thanks for any advice you all have.

-JD

[ANDY NEELY]

Just for the record, I had this same problem with a 2006 MDX with 88,000 miles. The engine light came on and the vtm4 light came on. I read the manual and, as to the engine light, it said that you had an emission problem and should schedule an appointment with the dealer. It also said the light would come on if the battery had been disconnected. I had replaced the battery the day before. As to the VTM4 light, it said schedule an appointment with the dealer, but if it starts flashing, stop. The engine got rough and I went to a repair shop. He showed me the remains of a spark plug and ignition coil. The plug was black and hollow. The coil had the wires removed, apparently blasted from it. They looked inside the cylinder with a camera and it was damaged by parts that had fallen into the cylinder.

I did not know such a failure could occur. Thanks for reporting this. I thought I was one in a million.