Code 34 - drywall dust??
Thread Starter
Pro
Joined: Nov 2005
Posts: 602
Likes: 0
From: North Bay Ontario
Code 34 - drywall dust??
'85 L98 all stock
Car has been running like a dream. I fire it up in the garage tonight - it starts and runs just like always. Backing out of the garage the "check engine" light comes on and stays on. hmmm...that's odd, I think... So, I pull out on the street and begin to accelerate and the engine bogs/sags and will barely raise rpms and then cuts out, but doesn't want to stall. I drive down the street, the situation does not improve, so I turn and limp back to the house. The engine nevers seems to want to stall and is idles fine, just no way to raise rpms to get much over 20 mph.
I pull in the driveway, shut it off and wait about 5 - 10 seconds. Hit the key, it fires up as usual, 'check engine' light is off, full power restored and I drive away and cruise into town. Close to an hour of driving and everything is back to normal.
I checked for stored codes and find a 34 - MAF sensor.
Here's the clicker...I've been doing some redecorating in the house and this involved a little bit of drywall work - I used the central vac to vacuum up the dry wall dust - the central vac is in the garage and the vette had a coat of dust on it (not a thick layer! - but definitely noticeable - bad, I know
)
Do you think the air flow sensing wire just needed to burn off the dust particles when I shut it down? The only problem with this theory is the air filter should have prevented that and the car wasn't running in the garage when there would have been a lot of dust in the air.
Time will tell if I get this intermittent code again - I plan to follow the steps to check if the burn off module is working on the week-end.
Thoughts?
Car has been running like a dream. I fire it up in the garage tonight - it starts and runs just like always. Backing out of the garage the "check engine" light comes on and stays on. hmmm...that's odd, I think... So, I pull out on the street and begin to accelerate and the engine bogs/sags and will barely raise rpms and then cuts out, but doesn't want to stall. I drive down the street, the situation does not improve, so I turn and limp back to the house. The engine nevers seems to want to stall and is idles fine, just no way to raise rpms to get much over 20 mph.
I pull in the driveway, shut it off and wait about 5 - 10 seconds. Hit the key, it fires up as usual, 'check engine' light is off, full power restored and I drive away and cruise into town. Close to an hour of driving and everything is back to normal.
I checked for stored codes and find a 34 - MAF sensor.
Here's the clicker...I've been doing some redecorating in the house and this involved a little bit of drywall work - I used the central vac to vacuum up the dry wall dust - the central vac is in the garage and the vette had a coat of dust on it (not a thick layer! - but definitely noticeable - bad, I know
) Do you think the air flow sensing wire just needed to burn off the dust particles when I shut it down? The only problem with this theory is the air filter should have prevented that and the car wasn't running in the garage when there would have been a lot of dust in the air.
Time will tell if I get this intermittent code again - I plan to follow the steps to check if the burn off module is working on the week-end.
Thoughts?
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
I used to have that same thing happen to me about twice a week. I never figured out why, and it hasn't happened in about 3 months. My air filter was pretty dirty and I replaced it, maybe thats what was causing it.
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
You got a K&N? Just cleaned and oiled? Extra oil will foul the sensor wire.
No K&N? Pull the intake hose, inspect, and bang the air filter out a little and see what gets freed up...
No K&N? Pull the intake hose, inspect, and bang the air filter out a little and see what gets freed up...
Thread Starter
Pro
Joined: Nov 2005
Posts: 602
Likes: 0
From: North Bay Ontario
no K&N - I've heard about the oil residue in the K&N causing this kind of problem, though. I have to admit, I'm finding it hard to link this to the drywall dust - it could be a dirty filter, I haven't changed the filter since getting the car 3 years ago and only putting on 10,000 km since purchasing it and the couple of times that I've looked at the filter, it didn't look like it had been there a long time. I just find it odd that shutting off the car, which is what activates the burn off module and the problem went away. Of course, I haven't driven it enough since this happened to know whether I have an intermittent issue or the ECM just had a glitch when it started.... time will tell
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
It is possible that some dust got sucked up into the filter and the filter just needs replaced or blown out. Also on the burnoff module, it is essentially nothing more than a computer chip inside of a metal box. Just like any other electronic device over time those solder joints can break or become lose and that can cause an intermittent problem before completely dying. Just FYI you can repair the broken joints on the chip, I did it with mine and have had no problems since.
Thread Starter
Pro
Joined: Nov 2005
Posts: 602
Likes: 0
From: North Bay Ontario
Good to know that if this becomes an intermittent problem it could be a broken solder joint. - thanks
Safety Car
Joined: Sep 2001
Posts: 4,134
Likes: 531
From: Glenbeulah Wi
'85 L98 all stock
Car has been running like a dream. I fire it up in the garage tonight - it starts and runs just like always. Backing out of the garage the "check engine" light comes on and stays on. hmmm...that's odd, I think... So, I pull out on the street and begin to accelerate and the engine bogs/sags and will barely raise rpms and then cuts out, but doesn't want to stall. I drive down the street, the situation does not improve, so I turn and limp back to the house. The engine nevers seems to want to stall and is idles fine, just no way to raise rpms to get much over 20 mph.
I pull in the driveway, shut it off and wait about 5 - 10 seconds. Hit the key, it fires up as usual, 'check engine' light is off, full power restored and I drive away and cruise into town. Close to an hour of driving and everything is back to normal.
I checked for stored codes and find a 34 - MAF sensor.
Here's the clicker...I've been doing some redecorating in the house and this involved a little bit of drywall work - I used the central vac to vacuum up the dry wall dust - the central vac is in the garage and the vette had a coat of dust on it (not a thick layer! - but definitely noticeable - bad, I know )
Do you think the air flow sensing wire just needed to burn off the dust particles when I shut it down? The only problem with this theory is the air filter should have prevented that and the car wasn't running in the garage when there would have been a lot of dust in the air.
Time will tell if I get this intermittent code again - I plan to follow the steps to check if the burn off module is working on the week-end.
Thoughts?
Car has been running like a dream. I fire it up in the garage tonight - it starts and runs just like always. Backing out of the garage the "check engine" light comes on and stays on. hmmm...that's odd, I think... So, I pull out on the street and begin to accelerate and the engine bogs/sags and will barely raise rpms and then cuts out, but doesn't want to stall. I drive down the street, the situation does not improve, so I turn and limp back to the house. The engine nevers seems to want to stall and is idles fine, just no way to raise rpms to get much over 20 mph.
I pull in the driveway, shut it off and wait about 5 - 10 seconds. Hit the key, it fires up as usual, 'check engine' light is off, full power restored and I drive away and cruise into town. Close to an hour of driving and everything is back to normal.
I checked for stored codes and find a 34 - MAF sensor.
Here's the clicker...I've been doing some redecorating in the house and this involved a little bit of drywall work - I used the central vac to vacuum up the dry wall dust - the central vac is in the garage and the vette had a coat of dust on it (not a thick layer! - but definitely noticeable - bad, I know
) Do you think the air flow sensing wire just needed to burn off the dust particles when I shut it down? The only problem with this theory is the air filter should have prevented that and the car wasn't running in the garage when there would have been a lot of dust in the air.
Time will tell if I get this intermittent code again - I plan to follow the steps to check if the burn off module is working on the week-end.
Thoughts?
It sounds like the MAS power relay or the MAS connection itself. Make sure the MAS connection is tight and clean and if the light comes back on replace the power relay.
