New Owner With Questions
Thread Starter
Pro
Joined: Sep 2003
Posts: 526
Likes: 1
From: Bowling Green KY
New Owner With Questions
Thanks for any help upfront but wanted to explain my two problems on my 1990 corvette.
First the tachometer does not work and I knew it did not work. I have access to another 91 dash unit that is in perfect shape and everything works. I am wondering if that would make the tachometer work again by putting in a new dash or if i shoudl start looking somewhere else to fix that?
Also when I put the car in cruise control and about 2-5 minutes into my drive i get a "service engine soon" light. This only happens when i put the car in cruise control. The car is 6 speed if that helps. Does anybody know what maybe the cause of that problem? Everytime it happens i am always away from a scanner but going to try and run out to the local parkway tonight and cruise and get teh light to come on and then drive in town and stop by auto zone and see if they can run there scanner on the car. Does anybody have any suggestions?
First the tachometer does not work and I knew it did not work. I have access to another 91 dash unit that is in perfect shape and everything works. I am wondering if that would make the tachometer work again by putting in a new dash or if i shoudl start looking somewhere else to fix that?
Also when I put the car in cruise control and about 2-5 minutes into my drive i get a "service engine soon" light. This only happens when i put the car in cruise control. The car is 6 speed if that helps. Does anybody know what maybe the cause of that problem? Everytime it happens i am always away from a scanner but going to try and run out to the local parkway tonight and cruise and get teh light to come on and then drive in town and stop by auto zone and see if they can run there scanner on the car. Does anybody have any suggestions?
Thread Starter
Pro
Joined: Sep 2003
Posts: 526
Likes: 1
From: Bowling Green KY
Well since its 90 its the first year of the new dash in i guess analog, pretty much the tach does not go anywhere. When I start it up it moves up to 500 it looks like and then doesnt move.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Autozone can only pull codes on a 96 or newer car (OBDII). The problem with the tach could be in the wiring or tach filter next to the distubitor. Not positive on how to pull codes on a 90, but someone here knows.
Cruising
Joined: Jun 2006
Posts: 13
Likes: 0
From: Virginia Beach VA
New Owner With Questions
On pre 96 vehicles, the OBD-I connector can be used to display codes via the "check engine" light. This is done by placing a metal paperclip in the pin receptors, located in the top row all the way to the right. This bypasses the ALDL signal and sends it to your check engine light. Now turn the ignition on but do not start the vehicle. From here monitor the light, which is now flashing a series of flashes. The code is a two digit number as determined by 1) a series of 1 second interval flashes and 2) a series of 1/2 second interval flashes.
As an example, code 12 (system OK) is displayed as follows: one- 1 second flash and 2- 1/2 second flashes. This will repeat until you remove the paperclip.
As an example, code 12 (system OK) is displayed as follows: one- 1 second flash and 2- 1/2 second flashes. This will repeat until you remove the paperclip.
Instructor
Joined: Jun 2004
Posts: 249
Likes: 0
From: clinton ut
Cruise control
You might want to check the vacuum lines at the vacuum reservoir (the black ball up front driver side under hood). I know mine worked sporadically until I cut off 1" of bad vacuum line.
