Check engine light and OBDII codes
 

When my Blazer goes above about 30mph the engine light starts to flash, nothing unusual here as there sounds like a bit of pinking/misfire, but shouldn't the OBD system then set a trouble code in memory ? When I slow down again the light goes out and there is no code set. Any ideas on what's going on here ?
Part of my problem is that it went to a repair shop which was totally incompetent ! (See my previous posts....) so I don't know what has or hasn't been done to the vehicle (but I did pay for new spark plugs) I'm pretty much resigned to having to take it in again but I'd like to know what's going on first.
Looking at the threads, it seems that most blazer owners outside the US struggle to get their vehicles repaired to a decent standard. Most shops just say "we don't touch American cars" which is at least honest and most of the garages which specialise in US cars tend to be in the East of England around Cambridgeshire, due to the US bases in that area but that's too much of a journey for me. If there are any other UK owners here, maybe we could start a British group ?

Time to find a new mechanic IMO. If you don't know what they're doing to you're vehicle then it's hard to diagnose and troubleshoot problems. I'm sure there is someone around you that knows about American vehicles and can properly work on your Blazer. If not you might just be making the problems worse.

How do i reset my monitors as i need them to pass inspection in texas sucks this thing is almost 20 yrs old should not have to do it Any help is greatly appreciated went out for a 100 mile drive did not help

A flashing CEL usually means engine misfires. Most codes require the event to produce a minimum number of fault cycles before a code is set.If you have a solid MIL light and no codes then your scanner may not be able to read those particular/non generic codes. You should get scanner capability that can display live data and in particular - misfires. Look to see if its cylinder specific or random.

George

Closing the 2009 thread. If there are still questions that have not been answered by GeorgeLG, please open a new thread, also giving your vehicle, year, engine type. Thanks.