Questions about Exhaust systems, Catalytic Converters and Headers/Manifolds

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2
votes
1answer
1k views

High short term fuel trim on one side when starting car?

2003 Ford Crown Victoria V8 Engine Dual exhaust 2 cats & O2 sensors per side Since some time last year I've been getting an error code throw up, with seemingly no regularity: P2197 - O2 stuck ...
9
votes
1answer
4k views

Is this what is making my car sound like a racecar?

Recently, my car (2000 Mercury Grand Marquis) started sounding like a racecar: the engine became very loud. There's clearly something going wrong with the exhaust system. I'm trying to understand ...
6
votes
2answers
4k views

Muffler off car. Safe to drive with exhaust open underneath?

So leaving work yesterday I heard a clang! - the muffler simply fell off. Further inspection revealed a lot of rust in one particular area on the pipe. Thankfully the forward muffler is still intact ...
2
votes
1answer
794 views

What causes the “pop” and “burble” noises on overrun?

I love the sound, just wondering what causes it.
5
votes
2answers
305 views

Performance Exhaust — what, how, why?

I've seen performance exhaust pipes on sale for cars and motorcycles, and my questions are these: What does it do? (better performance [and how so?]? better mileage? cooler sounds?) Is/how is it ...
3
votes
1answer
153 views

Exhaust smell emanating from old car?

I drive an '97 Subaru Legacy. Far as I know, it still works perfectly. Lately, there's been a bad exhaust smell around the car when I park and get out. I can smell it inside the car on occasion, but ...
3
votes
1answer
469 views

White smoke from tail pipe on operating temp start

I have a 89 Buick Century Custom. On the first start of the day, I have no problem. No smoke and no difficulty starting. However, after the car warms up, say, after driving to a gas station the ...
1
vote
5answers
3k views

How to determine by ear which part of exhaust needs replacing?

I have a 1.3L Skoda Felicia, (carburetter engine without catalytic nor other gimmicks). Since past 1-2 months I would hear the exhaust sound has changed, it became more and more audible and at full ...
4
votes
1answer
1k views

Car Stalls When Coming to a Stop

Make: Chevy Model: Cavalier (4 cyl.) Automatic Year: 1993 Miles: 230K Normally my Cavalier drives just fine without problems. However, if I drive for 45+ minutes then it will sputter and stall out ...
2
votes
1answer
609 views

Why does the price of Catalytic Converters vary so much?

My check engine light came on and the diagnostic code says it is a problem with the catalytic converters so I'm getting ready to schedule an appointment with a mechanic to take care of that. The ...
2
votes
3answers
3k views

Blue-ish smoke coming out from the exhaust

I have a VW Golf mk4, 1.9 TDI from 2001 with 230.000+ km on board and for some time now I have blue smoke coming out of the exhaust. The problem aggravates when I'm stuck in traffic or when the ...
3
votes
3answers
35k views

Why am I smelling exhaust inside the cabin of my car?

When I drive my car the first few miles, I smell exhaust inside the car with the windows rolled up. It happens when I have either the AC or the heat/air on... What's going on?
0
votes
1answer
447 views

What's the purpose of the cover on the catalytic converter?

On my 1990 Honda, it's falling apart. I'd like to just rip it off; will that cause any problems? More specifically: will the car pass New York state inspection with a missing cover?
1
vote
2answers
3k views

2001 Audi A4 just got really loud

Alright, So I'm driving to work. I'm stopped at the red light to go on the freeway. It turns green so I accelerate. I'm accelerating more than I would on a regular street but I didn't floor it. ...
2
votes
2answers
291 views

Muffler inlet corrosion problem

My 2001 Honda Civic needs a new muffler every two (2) years or so, because the inlet pipe corrodes just after the union. Is this a common problem, or would installing a better quality muffler prevent ...
4
votes
1answer
447 views

Biodiesel and DPF (Diesel Particulate Filter)

I read a little about DPFs and biodiesel. Some claim that there's a reduction in lubricity and/or viscosity of engine oil when using B30 or above. They warn about increased engine wear because of it. ...
3
votes
1answer
1k views

Can header / exhaust insulation replace metal heat shields?

Following up on my saga: What could be causing a distinct exhaust drone in a tight band around 3250 rpms on a 2004 Subaru WRX? At the end of that quest, we concluded that the right hand exhaust ...
1
vote
1answer
672 views

What could be causing a distinct exhaust drone in a tight band around 3250 rpms on a 2004 Subaru WRX?

EDIT: Additional information provided by LovelyWife(TM) - listening outside the car, she has proclaimed that the rattle / buzz / drone / resonance is coming from the front of the car and sounds like ...
2
votes
3answers
8k views

Rattle on Ford Focus, suspect heat shield

Ford Focus 1.8 Ghia '99 V A little while ago a large section of the aluminium heat shield above my exhaust came loose. Being in a situation where I needed to keep going and without tools, I crawled ...
3
votes
1answer
1k views

Is it possible to use biodiesel in a BMW 335d if I remove the DPF and remap the ECU?

The new (2009-current) BMW 335d sells in the U.S. with a DPF to reduce emissions, but which prevents the use of biodiesel. I've read about people removing the DPF and re-mapping their ECU to get ...
2
votes
1answer
143 views

How should I diagnose an exhaust “howl” when descending through 3200 rpms?

As mentioned previously, I have a 2004 WRX wagon with a stainless Prodrive circular-tip axle back installed around 2006. Lately, the weather has been nice enough to drive with the windows open and ...
1
vote
2answers
483 views

Why would gasoline engine exhaust smell like perfume?

Quite often I encounter a vehicle that has exhaust with rather sharp smell similar to perfume. As far as I know this is attributed to the engine malfunctioning - normally working engine will exhaust ...
11
votes
3answers
6k views

When car is standing still, I smell Diesel exhaust. Why?

In my 2003 Opel Vectra, the cabin air smells of Diesel exhaust while stopped at e.g. a red light. The exhaust smell goes away when driving, and it also doesn't come back if I turn the ventilation off ...
3
votes
3answers
240 views

How much of the exhaust is the “cat-back”

My brother-in-law's car has just failed inspection. One of the items listed was a "cat-back." Since the bill is astronomical, I was wondering how much of the exhaust system is encompassed in this term ...
15
votes
7answers
39k views

What is the best way to remove a stuck/rusted exhaust bolt?

I'm trying to disassemble the exhaust system on a 2000-2003 nissan maxima and I'm having trouble removing one last bolt.. its got a 14mm head and its just plain STUCK. I've tried soaking it overnight ...
2
votes
1answer
631 views

Are there any alternatives to the OEM muffler for a Volvo XC90?

I've been looking for an alternative to the OEM muffler for a Volvo XC90 2.5T AWD. There are a number of other Volvo vehicles that use the same drivetrain, but not one of the national muffler shops ...
7
votes
1answer
3k views

What are the tell tale signs of a catalytic converter that might be going bad?

I've owned two vehicles whose catalytic converters were recalled due two a couple of reasons: one being the quality of the CC and the other being a reduction in power due to a material building up and ...