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Exhaust leak?

I recently had some trouble with driving…three days in a row I got sick and dizzy after/during driving my Ford Escape 2009. I thought I had the flu or food poisoning. The fourth time I drove my car I saw double, had no good judgement, hit mailboxes and still made it to my destination. I vomited after getting out of my car and friends thought that I was drunk or on drugs. I don’t do either. I got a ticket for careless driving and spent the night in the hospital. They did not check my blood gases. I have had the car to three different places and no one can find any leak or anything. I have not had anything I last drove my car. A friend and I sat in the car in the driveway and I got red-faced (I have asthma) and don’t remember anything except her kicking me out. She stayed in for about 30 minutes and got some effects…slurring words, unsteady on feet.
Is there anything that could be leaking that mechanics might not find??? I am afraid to drive the car now and still owe lots of money on it. I am not a mechanic so I don’t know what to check and nobody has found anything. HELP!

Wow, that’s scary.

It certainly seems like you have carbon monoxide getting in though a leak that hasn’t been found yet. If you want my opinion, now that the legal system and presumably your insurance company are involved, the first thing I’d do (before trying to fix the problem) is to find an environmental testing service and have them analyze the air in your car so that you’ll have an official report in hand to show that you weren’t really responsible. After that, you should pick up a carbon monoxide detector from a home center or hardware store and put that in the car.

I’m surprised that three different places have been unable to find the problem. (Were all of them real mechanics and not chain shops?) It seems that you have no choice but to keep trying other places. Obviously you can only drive short trips with all windows down; otherwise it would be best to have the car towed. With a leak this severe, it seems most likely that it would be up front near the exhaust manifold instead of somewhere further back.

I had the Ford dealer check, Midas and my usual mechanic. They all said that they checked the manifold. There has to be something there…but they can’t find it. I bought a key fob co detector…it came today but I wonder if it would find a leak that is small. My pellet stove exhaust had a leak that I had fixed. Don’t know if the effects are accumulate or not.

The symptoms seem to be consistent w/CO. But other explanations are possible too. IMO you shouldn’t drive the car again until it is fixed or you’ve disproved the cause is CO in the passenger compartment. I guess if this were my car, I’d go to a department store and purchase a battery operated CO detecter for $50 or so, put it in the car, and test it myself to see what the CO readings were.

You might be getting sick from the offgassing of the chemicals used in the manufacturing of the interior components such as the glues, carpets, plastics, and vinyl.

Offgassing can occur from solids at any time after they’re manufactured. It can take days, weeks, months, and even years before the solid begins to offgas.

Formaldehyde is one such chemical used in the manufacturing of these solids. And depending on the concentration of the gas people can become disoriented, nauseous, and have difficulties with breathing. Especially those with asthma.

Some home inspectors use formaldehyde sniffers to detect for the concentration of this gas. So if you can locate an inspector with one of these sniffers and have them take an air sample they can tell you if the concentration is over 1 ppm.


Thanks…I tried a regular CO detector but the levels are not high enough to register on a home one. The little one that I just got should be able to though. I have never had problems with offgassing but it is worth investigating. One of the probs is that I live in a rural area in Mi. I am not sure if there is anyone that can do that but thanks for the suggestion, I will look into it.

You might want to check with your local fire/rescue squad. Sometimes they have access to these devices or can point you in the right direction. Also a call to your state or local health department, environmental division, could lead you in the right direction on testing.

If it’s outgassing you’d get sick sitting in the vehicle with the motor off.

Bing wrote:
You might want to check with your local fire/rescue squad.

That’s an excellent idea. I bet they can help.

I’ve seen this before, and this could be the cause.

You have an exhaust leak, BEFORE the upstream oxygen sensor.
The oxygen sensor sees all this unburned oxygen and believes your mixure is lean.
The PCM commands additional fuel to compensate for this perceived lean condition.
The AC system then pulls this rich mixture right into the cab.
The AC will do this, because the fresh air intake is very close to the exhaust leak.
So that rich mixture gets sucked into the cab.

I’ve worked on cars like this, and after fixing the leaks, everything was perfect again.

What they need to do is hook up an evap/smoke machine directly to the tailpipe and pump the smoke in.
Then they need to let the entire exhaust system fill up and look for smoke exiting where it’s not supposed to. It’ll probably be some degraded gasket or a cracked manifold.

CO poisonning does seem most likely. any small exhaust leak may be difficult to find if you can’t hear it. i have seen success using a smoke machine, more commonly used to find leaks in the evap system. you might also have the seals and any grommets arond the rear hatch checked, that’s another way for exhaust to get in, but there’s usually not much CO coming out that end of the pipe. most anything else i can think of would have an odor, such as mustiness from the ac vents, or rodent waste, etc…


part number 6522-10 is what is used to hook the machine up to the tailpipe.

I’ve used this very same adapter.

The car I was working on had an exhaust leak right at the manifolds.
The PCM then commanded additional fuel to compensate for the “lean” mixture
This rich mixture then came out at the leaking manifold and was sucked into the cab.

I almost couldn’t drive the car.
My head was ready to explode.
All was well my repairs.
Fuel trims and 02 sensor readings were perfect once again.

Get your car running in park, plug the tailpipe with a potato. Have someone nold it in if necessary. Look to see where the exhaust is coming out.

Having said that, I don’t see how a leak too small to be detected by a home CO detector could make anyone sick.

DB, my mechanic did do a smoke machine on it but couldn’t find any leak. Could it be under the heat shields?

Old timer, I had a leak in my house pellet stove too. That has been fixed. I also have asthma and am more prone to CO because of that…I don’t know if it accumulates in your system though.

@lesshadow, did your mechanic allow enough time for the exhaust system to fill with smoke.

You could be talking a few minutes.

The truck I’m thinking of took some time to fill up.

The heat shields could “trap” some escaping smoke.

By the way, what are your long term fuel trims and short term fuel trims?
Check it out and post back, please.

That could yield some good information.

Db, He said he let the exhaust fill up with smoke. What are long term fuel trims and short term fuel trims? He won’t be back at his garage until Wednesday.

Okay, sounds like your mechanic did things the right way.

Fuel trims are basically corrections.

It means how much fuel the PCM powertrain control module is adding or subtracting to achieve the proper air-fuel ratio.

For example, if the short term fuel trim was +25%, that would mean the PCM is commanding 25% additional fuel.

I’m not going into long-term fuel trim, because I could keep going and going . . .

Fuel trims are used by mechanics as diagnostic aids. In the case above, a mechanic might suspect a severe vacuum leak or a weak fuel pump, etc. Then he would bust out the evap/smoke machine and check fuel pressure and volume.

Anything that might make the exhaust leak intermittently?

This really has me frustrated…I owe big bucks on a car I am afraid to drive.