What are the symptoms of a clogged exhaust? Is the vehicle hard to start? Huge drop in MPG? Lower than normal idle? Will it generate codes? Just curious.
Packman
Packman
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I had it happen once, drop in mpg but I think that was before the fact and it was the cause of the clog, power was down (didn't have any to begin with, it was a 92 Metro, 3cyl of fury) but most noticeable symptom was the glowing hot cat. It got so hot it melted the crappy welds on the exhaust and it fell off behind the cat. Kinda cool though, after the exhaust fell off and I would drive it, it melted the snow under the car if it sat too long.
That's all I remember happening. Our trucks at work are high mileage, some have near 400k miles with original cats so they're bound to clog or break sometime, i'll post the results if it happens soon.88 Town Car (wrecked, for sale)
Walker OEM duals with muffler deletes -
My first registered car was a Hyundai Steller (somewhere around an '87). It had a small cat in the engine compartment and a regular cat underneath. The small one clogged up, and the symptom was basically an intermittent not responding when giving it gas to speed up. Starting and going slow were okay, but sometimes it just didn't want to get up to speed. The shop I went to localized the problem based on temperature, and I was able to drive it to my father's modest machine shop where I took out the honeycomb stuff. (The small cat had a bolt-on lid.) You could literally see how clogged it was. The car ran fine without it but got written off from being rear-ended before the next emission test.
2000 Grand Marquis LS HPP, a hand-me-down in 2008 with 128,000 km; 175,000 km as of July 2014
mods: air filter box 'tuba', headlight relay harness, J-mod (around 186,350 km), 70mm throttle body, KYB Gas-A-Just shocks, aluminum driveshaft, ARA3 PCMComment
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youll notice drop in power and and lower mileage. some say slightly higher engine temps. ive heard that one also a different smell to the exhaustCharlette - Brown 1977 Ford LTD - 351 Windsor 155K, Full Custom Pioneer system, green HID, interior & underbody
Alesha - Black 1982 Mercury Marquis - 255ci 178K, full custom Kenwood and Infinity system, lowered, dual exhaust, LED all the things
Tangerine Dream - Orange 1988 F-150 Custom - 300 i6 82k, Ghetto sound system, 5spd, 2WD, #farmtruckComment
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If you have a decent pressure/vacuum gauge, pull an o2 sensor and use the pressure gauge to measure pre-cat back pressure. Should be only a couple psi at idle and in the low double digits (there may be a spec somewhere) when revved. The clogged one I saw would peg the needleon the pressure gauge when revved in neutral.
85 4 door 351 Civi Crown Victoria - Summer daily driver, sleeper in the making, and wildly inappropriate autocross machine
160KMs 600cfm holley, shorty headers, 2.5" catted exhaust, 255/295 tires, cop shocks, cop swaybars, underdrive pulley, 2.73L gears.
waiting for install: 3.27's, Poly bushings, boxed rear arms, 2500 stall converter, ported e7's, etc
06 Mazda 3 hatch 2.3L 5AT (winter beater that cost more than my summer car)Comment
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Last really bad one I saw was on a VW Cabrio. Those used springs to hold the downpipe to the manifold. It was jammed up so bad that under load, it would push the pipe down and let exhaust blow through the gap. It also ran hot as hell and had no power.
Honestly though, converters rarely go bad without a reason. Burning lots of oil or coolant is definitely a reason though. The original cats on my Mark VII were fine at 225k, but the outer case on one had cracked and the pipes weren't in good shape either.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers
Everything looks like voodoo if you don't understand how it worksComment
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