Questions about Exhaust systems, Catalytic Converters and Headers/Manifolds

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12
votes
4answers
22k 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 ...
11
votes
3answers
4k 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 ...
8
votes
3answers
464 views

What does a water-like drop coming out of the exhaust of the car signify?

Sometimes while driving in the traffic, I come across a car or two which would be dripping water-like drop from it's exhaust steadily in a break of 4-5 seconds. I tried to ask a couple of people at ...
8
votes
1answer
2k 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 ...
7
votes
3answers
568 views

Catalysator broken? Odd rope coming out of the exhaust pipe

Old Volvo GL 440 and this is coming out of the exhaust pipe. No noise, all working fine but this cosmetic thing: does it mean that the exhaust gases are now not well filtered out? Does this mean that ...
7
votes
1answer
2k 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 ...
6
votes
3answers
2k views

How effective are exhaust patch kits?

How effective are exhaust patch kits in terms of longevity and limiting noise and leakage? Specifically I'm looking at using the kind that consist of heat-activated tape, an aluminium sheet and two ...
6
votes
3answers
9k views

Sputtering while driving & idling

[My car: 2004 Mazda 3] So, my wife came home from running some errands and told me the check-engine light was on and that the car was sputtering and felt like it was going to stall while stopped at ...
5
votes
2answers
1k views

should I replace gaskets when replacing exhaust?

I need to replace a broken section of exhaust. Should I replace the gaskets also? one of the gaskets is directly between the engine and the new part. The other is between the new and an old part of ...
5
votes
2answers
261 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 ...
5
votes
1answer
110 views

Does it make the most sense to replace an old car's entire exhaust system all at once?

Back story: The Check Engine light came on in my 2005 Chevrolet Malibu LS Sedan (V6 3.5L). I took the car to a mechanic #1 (M1), an independent shop. They replaced the EGR valve. A day later, the ...
5
votes
2answers
2k 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 ...
4
votes
1answer
189 views

Motorcycles: Way to maintain shiny chrome on exhaust outlets?

I have a motorcycle that has chromed exhaust pipes. I am worried that there will eventually be discolouration where the pipes join the engine, due to the heat. Is there a way to treat the pipes so ...
4
votes
1answer
334 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. ...
4
votes
1answer
63 views

Options for replacing rusted exhaust mounting bolts

The car is a 2005 Mini Cooper. The bolts that hold the exhaust mounts in place have rusted and snapped on both sides: I've taken up the floor of the boot and have located their heads on either ...
3
votes
3answers
17k 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?
3
votes
3answers
234 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 ...
3
votes
1answer
102 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
341 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 ...
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 ...
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 ...
3
votes
1answer
896 views

2000 VW Golf TDi (Mk. 4) grey smoke from exhaust before engine has warmed up

I have had my Golf for 8 years. It’s had good maintenance and a the record is kept by my dad. It’s just passed its MOT (Ministry of Transportation) test, and the mechanic mentioned that the tappets ...
3
votes
2answers
402 views

VW Golf 2.0 SDI (2005) - smokey when pulling away

Over the last 12 months I have noticed that as I pull away and put my foot down a little more, there is often a bit more of a cloud of smoke left behind. Its not thick smoke but still it seems like ...
3
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 ...
3
votes
2answers
534 views

Mass Air Flow Expected Values

I have a 2002 Audi A4 Quattro 3.0. I have a Vagcom USB cable and I am trying to diagnose the MAF sensor. I had a friend get some readings from an OBD2 scanner, which indicated that both precat O2 ...
3
votes
1answer
122 views

muffler positioning, and x-flow for specific sound

I am re-designing a ferrari exhaust system with 2 objectives: 1: enhance the specific high pitch raspy sound that you expect from a small ferrari V8. 2: achieve a good free-flow design. There is ...
2
votes
3answers
2k 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 ...
2
votes
3answers
6k 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 ...
2
votes
2answers
556 views

Failed emissions - high lambda, low HC and CO

My 2007 Daihatsu has failed the national car test on emissions. The readings at 3500rpm are: Lambda: 1.10 (normal range 0.97 - 1.03) CO: 0.02% volume (normal range below 0.20%) HC: 11ppm (normal ...
2
votes
1answer
220 views

2003 Honda Civic 1.7 vTec - White Smoke from the tailpipe

I have a Honda Civic 2003 gx 1.7 liter vTec stick shift 4 cylinder. Just today I had to put oil in my car. Drove for about 5 minutes got to a light and when I shifted into first gear a white cloud of ...
2
votes
2answers
285 views

Grey smoke when idling 1999 GMC Suburban, coolant system pressure loss

The most recent update is at the bottom. This looks interesting. The Smoke I'm confident the smoke is from burning oil. It's slightly blue, absolutely not white. If the engine is warm and I am ...
2
votes
1answer
554 views

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

I love the sound, just wondering what causes it.
2
votes
1answer
138 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 ...
2
votes
2answers
79 views

Is there a good online resource for exhaust system design? (theory)

I am looking for information on the effects of changing certain criteria in an exhaust system relating to its performance and its sound. I am unable to find any resourses relating to this on the net ...
2
votes
1answer
202 views

'04 Nissan Sentra - Smoke from engine compartment after long drive

My sister has a 2004 Nissan Sentra with a 1.8L engine, and a day or two ago she started noticing some (not a lot) smoke coming from the engine compartment after driving for a long time (i.e., more ...
2
votes
1answer
575 views

Attaching poorly-fitting exhaust components without welding?

I recently replaced my muffler, and attached it to the existing pipe using clamps around a short coupler pipe (sorry, I don't know the right name for these things) that fits around the outside the the ...
2
votes
1answer
497 views

Why is my exhaust pipe so rusty?

I think all cars exhaust pipes get very rusty after not very long. Why is that? I know that the pipe gets extremely hot, but how come that makes it rust more than any other part of the car?
2
votes
1answer
721 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 ...
2
votes
1answer
516 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
2answers
250 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 ...
2
votes
2answers
79 views

Improve engine sound of Mazda RX-8

I would like my 2006 Mazda RX-8 Shinka to be a little louder. I just don't know where to start though. The engine has such a nice sound, but I can't really hear it. I don't want it to be so loud that ...
2
votes
1answer
98 views

Changing the exhaust on a motorbike

I have a Yamaha XJ6 from 2012 and I would like to change the exhaust. But I have a choice. Do I change only the muffler or the whole "line"? Other than cost what are the pros and cons of changing ...
2
votes
3answers
658 views

Remove rounded manifold bolt

I'm trying to take off the manifold bolts on an old Chevy 350 (the ones that connect the manifold to the header). I got 4 out of the 6 bolts out, but 2 are extremely struck and rounded due to all the ...
2
votes
1answer
433 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 ...
2
votes
0answers
22 views

How to inexpensively replace missing baffles on a classic bike

Dilemma I have a 1980 Suzuki GS550L. Not only did one of the previous owners completely remove the baffles from the exhaust pipes, but they welded fender washers on the end of the pipes, so the OEM ...
2
votes
1answer
130 views

Mechanic Troubles And A Small Watery Oil Leak

My car is a 2005 BMW 525i E60 with about 180,000km on the clock. It has been well looked after and serviced. I don't get dealer services, but go to a mechanic who has always been good and uses the ...
2
votes
0answers
110 views

Dirt bike silencer core cracked/rusted

After removing and disassembling my FMF Factory 4.1 dirt bike silencer, I saw that the inner core was cracked and extremely rusty (having the potential for more cracks). I definitely want to fix this ...
1
vote
2answers
1k views

Exhaust Flame Kit

I have been searching over the past week or so trying to educate myself as much as possible before going ahead and trying to build an exhaust flame kit from scratch (the ones on sale on the internet ...
1
vote
1answer
74 views

What is this exhaust type thing?

What is this black exhaust type thing coming off the side of this land cruiser? What is it for?
1
vote
5answers
2k 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 ...