Intermittent check engine - MAF

[mint87]

Hi, this is my first post here, although I've been lurking and learning a lot over the last week or so. I'm soon to be the new proud owner of an '87 which belonged to my dad, but here's the problem.

The car doesn't get driven a lot (43K miles) and my Dad says the check engine light comes on when he first starts it up after its been sitting a while. He drives it around hard for a while and the light goes out. The GM tech says he needs a new MAF sensor. From this forum I gather I should replace the relays first, instead of shelling out 300+ for a new MAF sensor. I guess my question is, does an intermittent problem like this store a code I can retrieve to know for sure ?

Thanks a lot.

 

[JonM]

Mint...Check this site out...http://www.c4vettes.com/ecm.htm and Welcome to

 

[afree]

I had a similiar problem with my 1988 Coupe. The code is stored until the memory is cleared. This can occur due to a dead battery or by removing the fuse to ECM or disconnecting the battery. Provided the battery has not been disconnected you should be able to retrieve the codes for verification. Several others have described in their posts how to get the codes either by using the paper clip or wire method or you can go out and buy a cheap scanner for 25 bucks. At least when you buy the scanner you get the book that describes each code (although you can find that easily on line)
I should mention that my car actually ran fine and I did not immediatly replace the MAF sensor or the relays. The sensor did however go bad a couple of years later and it was replaced. If the sensor bites the dust then you will definetely notice the difference in engine idle and performance.
Also keep in mind that when the ignition switch is turned on the "burn off" relay allows current to flow through the sensor and it heats the small wire in the sensor effectively burning it clean.
I suppose it's a possibility that since the car is not driven that often that more "stuff" could build up on the sensor and give a false reading until it eventually burns off.
You might discover that just by driving the car more the problem goes away completely.
Good Luck.

 

[mint87]

thanks guys, this is very helpful. It will be driven a lot once I get it home!

 

[mint87]

fixed

I got code 34 from the ecm, replaced the MAF relays and cleared the code. The check engine light has been off now for 1000 miles ! Thanks to the great help here and tech info at c4vettes.com.