A/C Vents & SErvice Engine Light

alfonsi4 · 03-23-03, 08:49 AM

Hi,

I just picked up my 1996 C-4 and have noticed 2 problems so far.

1. A/C only vents out through the floor and the left upper vent. It does not come out the center or passenger vents. I have checked the obvious (vent controls) however I am stumped. My guesses include a vacuum line problem, but hopefully someone has a more direct item to check.

2. The Service Engine light is on. All gauges indicate all is well, and it runs well. I know sometime on my Tahoe it will come on and go away, and other times it indicates the air cleaner needs changed. I am sure it could be any number of things, but again some pin pointing may help.

Thanks in advance for all replies.

Tom A.

sumoboy · 03-23-03, 02:13 PM

Not sure but I think the vent flaps are electronically controlled buy elctric motors instead of vacuum diaphrams.

safety_match · 03-23-03, 03:01 PM

Quote:

Originally posted by alfonsi4
Hi,

I just picked up my 1996 C-4 and have noticed 2 problems so far.

2. The Service Engine light is on. All gauges indicate all is well, and it runs well. I know sometime on my Tahoe it will come on and go away, and other times it indicates the air cleaner needs changed. I am sure it could be any number of things, but again some pin pointing may help.

Thanks in advance for all replies.

Tom A.

Was the "service engine" light reset on the last oil change? You might want to reset this first and see?

Safety

alfonsi4 · 03-23-03, 10:49 PM

How do you reset the Service Engine Light?

Corvette-Pilot · 03-24-03, 07:15 AM

Quote:

Originally posted by alfonsi4
How do you reset the Service Engine Light?

Would disconnecting the battery work ?

As far as the AC vents,
Does you cruise control work?
I ask this because when I bought my 94 last Sept the vents only worked on the floor or defrost, nothing out the dash and my cruise was dead. I found thru research on this site a suprisingly simple solution.

Under the passanger side engine fuel rail trim cover (?) there is a vacuum connection into the intake manifold. It is a T-check valve. Mine was dry rotted from the heat big time !

I went the the Chevy parts counter, placed this thing on the counter. The guy went away and came back with the new part, at this point I hadn't said a word. He told me every GM car/truck with AC & Cruise used this piece and they always seem to fail.

$6 part, I bet it would cost $200 for the dealer to fix it and give you some BS story when this is most likely the first thing they check.

Worth a shot

safety_match · 03-24-03, 05:56 PM

Quote:

Originally posted by alfonsi4
How do you reset the Service Engine Light?

If it is just the reminder to change your oil you can reset it by:
Turn the key to the "On" position, but don't start the engine.
Press the ENG MET button on the Trip Monitor and release.
Within five seconds, press and release the ENG MET button again.
Within five seconds of Step 2, press and hold the RANGE button on the Trip Monitor.
The CHANGE OIL light will flash.
Hold the RANGE button until the CHANGE OIL light stops flashing and goes out.
When the light goes out, the Engine Oil Life Monitor is reset.
This should take about ten seconds.
If it doesn't reset, turn the ignition "Off" and repeat the procedure.

However, if it isn't your oil life you're talking about I would take the car in and have the codes read.

Good luck

alfonsi4 · 03-25-03, 06:49 PM

Thanks... I tried the solution, however I do not have a RANGE button. I did try the combination of other buttons, but to no luck.

I ordered a manual from Zip products... got an email saying it would be 2 weeks or so before the manual comes...

I feel so lost with a lack of knowledge about Corvettes... hope it's just a new guy thing...

wx briefer · 03-25-03, 09:36 PM

I had to replace my programmer for the A/C in my '96 last year to straighten out the function. It worked. Your problem may simply be a vacuum line pinched or disconnected at the programmer. It is located right above the accelerator on the firewall. If you would like to know how to go about this, contact me by e-mail. Make it subject 'vette a/c".

Corvette-Pilot · 03-26-03, 07:11 AM

Quote:

Originally posted by alfonsi4
Thanks... I tried the solution, however I do not have a RANGE button. I did try the combination of other buttons, but to no luck.

I ordered a manual from Zip products... got an email saying it would be 2 weeks or so before the manual comes...

I feel so lost with a lack of knowledge about Corvettes... hope it's just a new guy thing...

Check the owners manual I think it is in there under the maint section.

If you don't have it I can look it up for you.

You might also want to go and pick up a Chilton/Haynes manual. They are cheap and give you the basic info.

alfonsi4 · 03-26-03, 07:20 AM

Corvette-Pilot

Thanks for your reply.

Unfortunately I do not have a manual. I have ordered both the manaul and a Chilton's for it, but the vendor (Zip products) tells me it will be 2 weeks or more before shipping.

Any help is appreciated.

jmccloud · 03-26-03, 07:58 AM

Does the Driver's Information Center (DIC) vary from one year to the next? Wire color codes, RPO codes, etc do.
The following is the sequence for my '95 to reset the 'Change Oil' light

Turn the key to the "On" position, but don't start the engine.
Press the ENG MET button on the Trip Monitor and release.
Within five seconds, press and release the ENG MET button again.
Within five seconds of Step 2, press and hold the GAUGES button on the Trip Monitor.
The CHANGE OIL light will flash.
Hold the GAUGES button until the CHANGE OIL light stops flashing and goes out.
When the light goes out, the Engine Oil Life Monitor is reset.

To reset the 'Service Engine' light, disconnect the neg side of the battery for a few minutes. If the service engine light comes back on after battery disconnect, have the codes read. Your '96 will have OBD II so a reader is necessary to check the codes.

Hope this helps

Corvette-Pilot · 03-26-03, 12:00 PM

Quote:

Originally posted by alfonsi4
Corvette-Pilot

Thanks for your reply.

Unfortunately I do not have a manual. I have ordered both the manaul and a Chilton's for it, but the vendor (Zip products) tells me it will be 2 weeks or more before shipping.

Any help is appreciated.

Geuss it's too late now but....
Chiltons can be found in any parts store or even Wal-Mart

The GM manual can be ordered direct from the publisher "Helm"
I found mine on ebay for a lot less than direct.

"jmccloud" explaination above sounds right, worth a shot.

alfonsi4 · 03-26-03, 06:21 PM

jmccloud,

Your instructions worked... well finally. I kept trying it and did not see the "change oil" light come on... I was looking for it on the panel where the "service engine" light was at... my left hand was on the wheel and blocking the line of sight to the left side of the instument panel so I was not seeing the "change oil" indicator... the finally...

... after all that the "service engine" did not go out... guess I will have to have it checked.

Do other places besides a GM dealer usually have equipment to read the computer?

Thanks for the instructions

safety_match · 03-26-03, 06:51 PM

Quote:

Originally posted by alfonsi4
jmccloud,

Do other places besides a GM dealer usually have equipment to read the computer?

Thanks for the instructions

Yes, any reputable shop will have the ability to read fault codes. Many people on this site have even bought their own code readers. Perhaps someone call tell us how much they cost to buy?

Corvette-Pilot · 03-27-03, 07:15 AM

Quote:

Originally posted by alfonsi4
jmccloud,

Do other places besides a GM dealer usually have equipment to read the computer?

Thanks for the instructions

In my area places like Autozone do this for free.
They figure if they tell you what is broke then you will likely buy a new piece while you are there.