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White Smoke Billowing From Exhaust After Repairs

So I brought the Nissan Xterra back to the Southlake Nissan Dealership to get a diagnosis, after they “fixed” it. The service manager, Randy, called me back later that day and stated that a piece of the old catalytic converter was sucked into the engine and got into one of the cylinders. I should add that the day I brought it back, the engine started sputtering and the check engine light came back on and was flashing, in addition to the billowing white smoke. Randy said he can’t fix the vehicle and it needs a new engine. Now if his story is true, then isn’t this something his mechanics should have figured out the FIRST time I brought the Xterra in to get fixed? He charged me $3,000 in repairs and I still don’t have a running vehicle. If he would have told me the first time I brought it in, that major engine work was needed, or that the entire engine needed to be replaced, I never would have agreed to him replacing anything on the vehicle. This whole situation feels wrong. There has to be some legal action I can take regarding this matter. I’ve already contacted Nissan Corporation and am awaiting their reply.

Is any of that in writing? Start writing letters and go up the chain. Start with his boss.

Randy, called me back later that day and stated that a piece of the old catalytic converter was sucked into the engine *

I may be wrong but the catalytic converter is part of the exhaust system to take exhaust gasses from the engine and out of the tailpipe not sucking thing’s back into the engine I don’t understand how that could happen.

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I talked to 3 different mechanics after Randy told me this story, and they had never heard of a piece of catalytic converter being sucked into the engine. Like you said, the exhaust blows out the tailpipe, it doesn’t get sucked into the engine. I think Randy’s mechanics made some mistakes when trying to fix the vehicle, and he’s trying cover the tracks.

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he’s trying cover the tracks.

That is what I was thinking.

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On most vehicles, this is true. Unfortunately, certain Nissan engines have the (very foolish) design feature that instead of having a pipe connecting the exhaust manifold and intake manifold with an EGR valve in between, they use the camshaft timing to hold the intake and exhaust valves open simultaneously for a short time during each revolution of the engine. Even more unfortunately, there is a “pre-cat” in the exhaust manifold, and if this breaks apart, pieces of it can and do get sucked into the intake, resulting in cylinder wall damage.

This, of course, is something a Nissan dealer should know about, and have warned you about, and if they did not, that would be gross negligence on their part.


Thank you for the education I am not a mechanic and have never heard of that that is a foolish design make’s one wonder what they were thinking.

Thanks for that bit of information. With that said, Randy’s mechanics should have identified the issue when I initially took he Xterra to the dealership to be diagnosed and fixed, not the second time around, after it was too late.

That would be magic.

Nissan happen to use this design on multiple engines, so it is not only Xterra what was affected.

The important piece of info here is that prior to the repair it was not a problem, it happened right after repair, so it may be an indicator of the job improperly done by the dealer.

This may still be within the small claims court limits to try persuading the dealer to fix their mistake.

Their offer to “help” me was to put a rebuilt engine in the Xterra, with a 1 year/12,000 mile warranty on it, for the very low price (sarcasm) of only $3,800. I declined this offer and told them I would see them in court.

As I alluded to in my earlier post, you as a member of the car-buying public are not expected to have the same level of technical expertise as a professional mechanic or dealership service advisor. As a customer, you brought your vehicle to the dealer’s service department for them to diagnose and repair the problem. You didn’t bring it to them and say “I want such-and-such parts replaced”.

Their diagnosis was $3100 worth of repairs, which you accepted, presumably based on an assurance that the problem has been correctly diagnosed, and that having this work done would restore the vehicle to proper function. If there was any doubt as to the completeness or correctness of the diagnosis, or the risk that additional engine damage may have occurred, that should have been communicated in writing before any repairs were attempted.

Therefore, there are only three possible explanations for the fact that the engine has ingested chunks of the “pre-cat” and suffered cylinder wall damage, and every one of these explanations is a direct result of negligence on the part of the servicing dealer.

  1. The problem was never diagnosed correctly to begin with. Before the dealership mechanic had ever touched the vehicle, the “pre-cat” inside one, or both exhaust manifolds had overheated and broken apart and pieces of it had been sucked into the engine.
  2. The problem was correctly diagnosed, however during the repair operations of removing and replacing the exhaust manifolds with integrated “pre-cat” converters, the mechanic somehow caused the breakage of the “pre-cat” converters, and failed to properly clean this debris from the engine prior to reassembly.
  3. The problem was correctly diagnosed, and the repairs were correctly performed, however, the replacement part(s) subsequently failed, which resulted in chunks of the new “pre-cat” converters being ingested into the engine.

It is not necessary to prove which of these three scenarios actually occurred, or even which is the most probable explanation. All three possibilities point to gross negligence on the part of the servicing dealer.

The point you need to reiterate in your complaint, and in court is that you brought your vehicle to Dealer Shop for diagnosis and repair, and that Dealer Shop performed the diagnosis and recommended $3100 worth of repairs to restore the vehicle to proper operation (subject to their normal shop warranty). Immediately after having the repairs done, additional engine damage has either been discovered, or occurred due to the work which was done. Thus, Dealer Shop needs to either refund the cost of the incorrect diagnosis and repairs which did not solve the problem, or remedy the additional problem created by its shoddy workmanship or defective parts.


Nothing more I can add except that I have never heard of converter substrate getting into a cylinder.
Also, in every single instance where foreign debris (generally a piece of hard carbon) has been in a cylinder (even BB sized) the particle will glow red very quickly and cause severe detonation which in turn leads to knocking. Sometimes severe knocking that sounds like a connecting rod bearing has given up.

There is a huge difference between “discovered” and “occurred during work”. Only the later one is a liability.

This is true if the vehicle was brought in for an unrelated problem. For example, Customer brings vehicle to Dealer Shop for brakes and the next day, the timing belt fails, and the engine is ruined. No reasonable person would hold the shop responsible under that circumstance.

This is not true if the original diagnosis was flawed, or if the mechanic and/or service advisor knew–or should have known–that the problem which was diagnosed had a high probability of causing additional expensive damage on this type of vehicle, and failed to mention this. This is really no different than a mechanic considering replacing head gasket(s) in an engine which has had coolant leaking into the oil. It is up to the mechanic or service advisor to inform the customer that the proposed repair might be short-lived, that additional expensive damage might exist, and that replacing the engine or having it rebuilt by a machine shop is the only solution which will guarantee long-term reliability.

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I’ve heard before that early-2000s Nissans have this problem, it was specifically the reason I avoided Nissans between 2000 and 2010.

This was discussed on this forum before:

VQ40DE on XTerra is a “big brother” of VQ35DE.

Here is some more from Nissan-specific sources:

I agree completely. If a piece of the old catalytic converter was sucked into the engine, then this should have been detected when I initially brought the Nissan in to be diagnosed. He said “well, we don’t have crystal balls to know these kind of things.” What am I paying $140 for up front then for them to diagnose the issue, if they can’t detect it? Funny, when I brought it back the second time they were able to detect that the catalytic converter piece damaged cylinder 6 of the motor, within hours. I’m leaning towards this occurring during their replacement of the catalytic converter. The service manager seemed convinced that the Xterra was running fine when they were done, but less than 24 hours after their mechanics touched the vehicle, it was blowing clouds of white smoke out of the exhaust. When I drove it to the dealership the 2nd time, the check engine light came back on and was flashing, and the engine felt like it was sputtering.

I spoke to the service manager and the service director, they both claim this is no fault on their service department’s behalf. They refuse to refund my money. So I’m sunk $3,000 and have a vehicle that is now in worse condition than when I brought it in to them.

I’d like to take them to small claims court to get my $3,000 back. Do you guys feel I have a substantial case against them?

Actually, based on these facts, dealer will likely get the stand that @Kevin219 neglected to stop driving his car when clear indication of the damage inducing failure was present, thus was a major factor contributing to the engine failure.

The “check engine light” on for a long time and especially light flashing is not an indication of “take your time and show your vehicle to the shop when you feel like it”. The flashing light is “stop right here and now, tow it to the shop to avoid further damage”.

It is quite likely that the catalyst was damaged when driving misfiring engine to the dealer, so it will be hard to prove the dealer to be at fault for anything but not addressing the entire issue, not only a part of it. Once the waters get muddied by the owner sharing the fault, the end result may become more financially beneficial to lawyers than to the owner.

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The only place I drove the vehicle, when the engine light was flashing, was home from work. 15 minute drive. The very next day I had it towed to Nissan. Regardless if I drove it till the engine blew up into a million pieces, I took it to them for a proper diagnosis, and they failed to diagnosis it properly, charged me $3,000, which I paid under the pretense that the vehicle would be running and functional after the repairs were done. If they couldn’t diagnose the problem correctly, fully fix the vehicle to a proper running condition and believed that there could be potential engine damage, they should have communicated this to me. I could have then said: “forget it, I’m not paying for these repairs.”

The bottom line is: YOU (not them) drove the car with misfiring engine, so you melted O2 sensors and catalysts, this is likely documented in the paperwork very nicely.

It might very well happen that the abrasive ceramic dust was already on the piston rings and making the damage, but it might require some additional time until that damage was enough to give the next set of failure indications (smoke/clunking).

Given that, if I was a dealer, I would take the next stance:

  • the customer brought in the vehicle with a history of 2 weeks of CEL on
  • customer stated CEL was blinking as he drove it and it was misfiring, that’s the complaint on hands, DOCUMENTED
  • we replaced spark plugs and coils as plugs were worn and we did not want to take chances with coils either
  • we repaired the immediate damage to O2 sensors and catalysts, which were definitely attributed to the severe misfire
  • that at the moment the vehicle was discharged from the shop, it was operating fine, customer accepted the delivery
  • we can not guess if further damage existed or not, it was not apparent at the repair time

Now, they will make a good argument that if hidden damage was present, they would not be able to observe it, since it is not “chunks” what damages the engine, but the fine abrasive dust, which disintegrating catalysts may release (or may not?).

Further, supposedly Nissan was addressing the issue after initial early-2000 set of failures, so dealer would not know for sure if this damage is likely to occur or not, this is not exactly their bowl of soup they are dealing with on daily basis.

So, the pitch will be that the damage is most likely due to the owner driving the vehicle (a couple of minutes would suffice, he drove 15 minutes with misfires) and they will absolutely deny any wrongdoing.

If I was a lawyer, I would gladly accept the case on the “pay as you go” basis, as it smells like a great cash-generator with no fast conclusion and a lot of effort to burn in.

BTW, if any Nissan’ TSB existed on the SOP for the disintegrated catalyst failure repairs for the particular model/year, that might be actually a game-changer.

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