Is my car a death trap?

The guy at the muffler place says I have a cracked exhaust manifold. He also says he can’t get the parts until after Thanksgiving - in fact, until Dec 3, because Dec 2 is the opening day of the PA hunting season, which is, apparently, an undeclared holiday. I’m supposed to drive, with my family to Virginia for Thanksgiving. The muffler guy says that should be fine - highway driving will generate enough airflow to keep us from all dying of CO asphyxiation.

I have two questions. 1) Am I putting my life and the life of my family at risk by taking this car on the road?
2) The shop has quoted a very high figure to repair the problem, with a slightly smaller price if they can salvage the O2 sensor. Some internet shopping suggests that the prices quoted are on the high side, especially for the O2 sensor - how much should a forward O2 sensor for a Toyota Matrix cost?

Yes. I wouldn’t do this unless I could drive with my windows down. Air going into the heater may come from the engine area.

agree with the windows comment, but I would also say you have to do what is comfortable with you.

assume you have driven it every day for the last 6 months, what’s the difference? drive that thing for another week won’t make much of a difference.

just crack the window every now and then. but you gotta decide for yourself.

One way to know for sure ?
Take a home CO detector with you on your trip.
If it alarms, open the windows.
If your home CO detector is battery operated, just take it with you.
If not , you can pick one up at any WalMart type place.

I believe OP’s exhaust manifold also incorporates the warm up cat. That would explain the very high price of the part.

The shop is being smart to bring up the possibility that the oxygen sensor may be seized. I’ve run into this scenario myself. Penetrant did not help. An oxyacetylene torch did not help. The sensor came out in pieces.

My problem is not with the idea that the O2 sensor might need replacing. My problem is that I was quoted a $200 price, and I can’t find a sensor online for anything approaching that price - most seem to be $40 or $50. Of course, the shop is staffed with professionals, and I am not a professional, but the cost seems excessive. The manifold seems reasonably priced.

Here’s some information

Denso manufactured the sensor for Toyota

Denso parts aren’t cheap

If the part has the Denso name AND the Toyota name on it, the price is even higher

Online parts are always cheaper

All shops mark up the cost of the parts

That is normal and fair

If the shop only charged you what they paid for a part, they wouldn’t stay in business very long

I am a professional mechanic

Charging you $200 for that sensor is not out of line

Thanks. That explains a great deal, and makes me feel more comfortable about what I’ve been quoted as far as price goes. Now to see how the CO detector reacts to the car…

You have family. Don’t go or rent a car if you can’t get it fixed in time.

I agree with @dagosa

As a mechanic, I have experience driving cars with exhaust leaks

You can get a major headache in a very short amount of time

You can also get very drowsy

Not to mention the brain cells that you’ll be killing

So, it is to be avoided

Right. CO sensor sensed nothing today, but we’re renting a car for the VA trip. Thanks all for your good suggestions!

Did I miss it or was the year on your Matrix omitted from the original post? Thanks in advance.

Good decision on the car rental. I have a customer who had to make a 300 mile drive for business once or twice a month. Once when coming in for routine service he mentioned that several times on his trip to Spokane he ended up with a headache and someone thought it might be related to 5 hours in the car. He did in fact have an exhaust leak. Couldn’t really hear it or see it, and I never would have found it it I wasn’t looking, but fixing the leak also fixed his headaches.

When I think about cars causing health problems reminds me of my 1971 Ford Maverick. I was doing quite a bit of long distance driving at the time. I was also fighting hemorrhoids. I was about ready to have surgery when my problem went away on its own. It finally dawned on me that the problem was due to the seats and ride of the Maverick. I had traded the Maverick for a 1978 Oldsmobile Cutlass Salon Coupe. The Cutlass had the 4-4-2 trim package which included bucket seats which, for me, were very comfortable. Before I owned the Maverick, I owned a 1965 Rambler Classic. It also had seats that were quite comfortable for me and I didn’t have the hemorrhoid problems.
I remember reading accounts of people suffering headaches in the 1961 and later Corvairs with the heater that heated the air from the exhaust manifolds. If the engine seals were bad, exhaust fumes could leak into the car. This was the problem that Ralph Nader missed with the Corvair. The original 1960 Corvairs had a gasoline heater and apparently the fumes didn’t enter the passenger compartment.

Ray mentioned on the show a while back that cracked exhaust manifolds are a common problem he has observed on older Toyota engines, esp the Corolla engine. I think he was referring to pre-2000’s Toyotas at the time, but I expect this isn’t an uncommon problem for Toyotas in general. OP can stop by a Toyota dealership parts dept and price the OEM O2 sensor. Lower prices are likely available on non-OEM versions on the internet, but for O2 sensors I think it best to stay with the OEM version. And the shop may indeed be able to save and install it in the replacement manifold. You might can save some money if a replacement manifold can be found from a recycler (junk yard). Has your shop explored that option?

About the driving issue. It can probably be done. But why risk it? Why be bothered by the worries? Rent a car for the week instead.

4a-fe and 7a-fe engines were notorious for cracked exhaust manifolds

That is most likely the reason you won’t find a good manifold in the junkyard

And if the manifold has a cat. in it I don’t think a junk yard can sell it at all.


You hit the nail on the head!

In Los Angeles, the junkyards cut out the cats before the cars are even dumped in the self service yard

And even those used auto parts places aren’t allowed to sell used cats