Question about 2001 Chevrolet Blazer

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Backfire on cold start up blows vacume plug off of intake

This plug i refer to is on the top of the engine,0n the right side in the back.It has an o ring that seals it with a push and a twist which locks it down.It has two different vacume lines running through it.One to the air intake,and one to the valve cover.It backfires so hard it litterally blows it out and breaks the plastic lock down keepers.upon reinserting this part it will start all be it somewhat difficult and runs fine,smooth with no idle problems.Start up after it warms is fine,no backfire.

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SOURCE: 2000 silverado 4.8 v8 runs bad when it is cold out side.

Try replacing the coolant temperature sensor for the injection system.

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SOURCE: 1990 Chevy Scottsdale 1500 wont idle when first starting cold

ICM idle control module, loc throttle body, it may be dirty, remove clean or replace, its easy..

Posted on Jul 29, 2009

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SOURCE: Vaccum hose diagram for 97 chevy tahoe 5.7 liter

I have the diagram you need. If you send me your email I will scan it off and send it to you.

Posted on Sep 12, 2009

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SOURCE: 5.3 chevy hesitates when cold runs fine after warming up

I have same problem, Chevy told me it was probably a seal affecting fuel air ratio and when warm seal expanded to stop air leak. I forget which seal but they also said to check plastic case around seal because it will warp and may also need to be replaced. It was located near top center of engine. Please let me know if you figure it out.

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SOURCE: Blazer hesitates, backfiring and bogging out

auto choke sticking on get it checked out..

Posted on Nov 18, 2009

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Why does the mass air flow code comes back after replacing the sensor?

Mass Air Flow sensor just measures incoming air flow at a predetermined rpm/load. The computer is saying the flow measurement is not correct. This can be caused by mechanical faults within the engine like a bad valve seat or timing chain but would generally be accompanied by backfires through the intake. Usually its caused by a vacume leak between the sensor and the intake valve,like the intake manifold,loose intake pipe clamps, broken vacume lines,a leaking vacume brake booster [it will hiss loud when you apply the brake],bad spark plugs/wires, a clogged catalytic converter, stuck open egr valve or pcv valve,bad oxygen sensor or even a very clogged air filter. I know there is a lot listed but the MAF or MAP sensors show general flow through the engine that can be affected by several things. A vacume tester from your local auto parts store is about 30bucks and usually has instructions how to test for vac. leaks within the engine also to determine a if thers is bad valve seat or clogged exhaust.

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