I just had my motor replaced (again) and with 150 miles on the new motor I got a flashing check engine light a few times and now it's solid. Anyone have any idea what could cause that? Also is there a cheap way to clear/read the CEL?

 

You need to get the cel read before anyone here can help you.
Go to Pep Boys or something like that ... they will do it for free (read the code)

I wouldn't erase the code however as you just had the engine replaced it should be under warrentee ... take it back to the garage that did the engine install and get them to fix it.

Knowing some more detail about you car would help,
Year
Mods
Mileage

 

CEL just 150 miles after an engine replacement...going back to the place that did the work seems like a good move.

You can buy a code scanner for as little as $30. IMHO, it's worth having at least a basic one like that.

Ken

 

So I just ordered a scanner off Amazon. Where do I plug it in when I get it?

 

You'll find the OBDII port under the dash/steering wheel, above your pedals.

 

Just temporary, i just disconnect one of the battery cable for a minute or two, and it should disappear. Plus, it's free

 

So I bought a scanner and got codes for: P0300 and P0301 Pending

A quick search tells me this:

P0300 Random misfire detected Flash/ON 1 or 2 Misfire ´ (See DTC P0300 )
P0301 Front rotor misfire detected Flash/ON 1 or 2 Misfire ´(See DTC P0301, P0302 )

What does See DTC mean?
Also do you think this is something I should be concerned about?

 

I would be pretty concerned if a new or reman engine I just had put in was misifiring. Don't clear the CEL's and drive to the place that replaced your engine and complain. Some people do get bad reman engines from Mazda, it just happens.

 

Why would anyone want to clear a code without knowing what it was?

Ken

 

If you don't have the time and money, and specially looking at that annoying code inside your dash everytime you start the car...yes, just temporary until you have time to fix the issue.

 

You won't know what the issue is if you clear it..... I'd rather stare at the light ALERTING me something is potentially wrong with the car then to just brush it under the table and have it crop back up when things are worse...

OP, just go to autozone and have it read for free.