1999 Chevy Astro miss fires

Hello,

Do you have the actual code it should be something like P0300 or P0301 - 306. If not your local parts store can pull the codes. Post them here.

Also when was your last tune-up?


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I get bought it it's a nice van so I don't know when it was last tuned-up. The code was P0300

OK,

Here is the code def....

P0300 Random/Multiple Cylinder Misfire Detected

So, first thing I would do is pull a plug or 2 and see what they look like. If they look worn then I would do a tune-up and see if that corrects the problem. 8 out of 10 time is does.

If not other possibilities are....

Vacuum Leaks

Low Cylinder Compression

Weak Fuel Pump and/or Pressure Regulator

For more check out the link below...

https://www.2carpros.com/first_things/why_does_my_engine_run_rough.htm


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Thanks for your help I had a vacuum hose that was broken in two

Ok, great did that fix the Misfire? If so congrats on the fix.

If not let me know so we can do more diagnosis.



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