Question about 2002 Chevrolet TrailBlazer

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Loss of engine power, loud whistling noise

I have an exhaust manifold leak that makes a loud ticking noise. It ran terrible and was throwing several codes, mainly the exhaust actuator sylnoid. I replaced that(was all caked with oil and the screens plugged)flushed the engine and replaced it with new oil. Now it runs better, but I still dont have power and have to be in 3rd in order to get to and maintain 55 mph. There is a loud whistling noise that starts under a slight load and gets louder. If I push it, i can get it to have the check engine light come on and have it will miss fire at idle, oil pressure drops off to zero. Throws a code for O2 sensor and miss fire #4. Both O2's are replaced and changed plugs. I read something about using only ac delco plugs? does that make that much difference? Would my exhaust manifold leak throw it off that bad?

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  • 1,194 Answers

Exhaust manifold leak? That's not common. You talking about the VVT near the manifold at the top of engine above the power steering pump? Yes indeed, AC Delco is the only one our engines love. 41-103. Obviously you have P0304, what other codes?

Posted on Mar 16, 2017


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Posted on Jan 02, 2017

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SOURCE: Truck has a hesitation just off idle and service

Map sensor is usually on the firewall and has both an electrical connection and a vacuum hose going to it. Mass air flow is in the air duct from the air cleaner to the throttle body. Two small wires are stretched across it's bore. clean them with a Q-tip and carb cleaner.

Posted on Aug 05, 2009

  • 97 Answers

SOURCE: 2001 S-10 with 4.3 misfire

Check for vacum leaks make sure hoses arn't cracked and are routed correctly. check for leaks at throtle body, intake manifold, egr valve and pcv system. also check to make sure pcm is grounded correctly. Check injecter harness connectors aswell.... Hope this helps if all this looks good... you may have to take it to a shop where they can make sure the injecters are firing and compresion is correct.

Good luck :)

Posted on Jan 20, 2010

  • 12 Answers

SOURCE: difficulty starting with loud tick throwing code

ignition coil is the problem.

Posted on Feb 09, 2010

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SOURCE: 2001 Silverado 5.3 1500 extended

P0300 is caused by all the cylinders having a random misfire, this is the rough idle u have, i suggest u have the fuel injectors professionally cleaned (not the snake oil u pour in the tank, that doesn't work) with the GM high pressure injector cleaning machine, and also have a cylinder power balance test run, u may have worn valve guides or a worn camshaft. Be prepared for the fact u may have a worn engine problem

Posted on Nov 01, 2010

  • 227 Answers

SOURCE: 91 camaro ses engine light

what size engine is it

Posted on Feb 16, 2011

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