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My 2004 K1500 4.8 4x4 won't pass inspection, codes 420, replaced cat bank 1, code 455 now? I had GM dealership do service bulletin on heater blower motor relay and now "service air bag" light is on as well. Just did a tune up, plugs, wires, tranny,etc. It helped rough idle a lot but still will stall at strange time. I feel it's partially electrical because of bulletin on instrument panel cluster which I learned about after I don't qualify for free replacement due to mileage,(118000) and age. It displays different issues with no specific pattern except for "replace fuel cap" at approx 4-5 miles of driving from a cold start and after tank gets below 1/2 tank. I can't afford to replace/repair I need to troubleshoot 1st. I've asked many mechanics and none of them have heard of my symptoms. Where can I can a detailed diagram of the vacuum and fuel lines so I can check for leaks?

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The only solution I can offer is temporary and could help you at least pass inspection.

  • When you fuel tank is near empty.
  • Fill your car with 3 Gallons regular gasoline and 3 Gallons E85 gasoline.
  • Erase the error codes and drive around for a little while.
  • Then get the inspection done.
  • After you pass inspection fill the car the rest of the way with regular gasoline.

WARNING: This is a last resort effort. Prolonged use of Ethanol (E85) in engines not designed for it can deteriorate rubber fuel lines, oxidize aluminum, and dry gaskets causing them to crack.

Posted on Nov 16, 2013


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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: Rough idle

Jeep has been having a problem with this. i take it u have a 4.7L or a 3.7L. when the when to fix this problem they should of replaced all the valves (intake and exhaust). theres a tsb on this and the dealer can look it up. even if you paid for the service they will fix it for free cuz it wasn't fixed the first time. take it back to the them and tell the to read the tsb and fix it right.

Posted on May 15, 2008

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SOURCE: 95 GMC Jimmy 4.3l W vin rough idle

My problem was solved when I repaired my 4 wd activation dash switch. The switch was contacting on 2WD & 4HI at the same time. The front differential activation is vacuum activated possibly creating a tug of war that didn't actually engage it but drained off vacuum from the engine? A theory at best but stumbbled across it because I knew the switch wasn't working properly I repaired it and low and behold rough idle disappeared and all is good for 3 weeks running.

Posted on Dec 10, 2008

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SOURCE: 1989 Corvette starting and idle problems

my 89 corvette is hard to start when it is cold, and runs very rough for about a minute. replaced the IAC and Maf sensors had the throttle body cleaned, now it idles very high and emits the same problems. i also had the injectors cleaned.

Posted on Sep 19, 2009

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P1884 code 2005suzuki forenza P0420 P0134 P0138

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first fix is to check the cat converter is operational ( not cracked and blocking the exhaust system)
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P0133, P0420 and P0430 i went to MCV for inspection and they rejected the car. gave me the above codes. when i went to authorized mechanic, he told me that both the catalyic converters are bad and cost...

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also refers to oxygen sensor (O2S) 1 bank 1--slow response ===causes ---wiring ---O2S
also refers toHO2S 1 bank 1--no signal====causes wiring ---HO2S
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