OBD I and Actron Scanner Question

[C4Tom]

My gas mileage has dropped considerably recently, from 21mpg avg down to 18mpg avg. ad Two months ago the check engine light came on while steady driving on the interstate at 60mph. But it was off after a restart and it did this a couple of times.

Now mpg is way down so I stopped by an AdvanceAuto and asked them to scan it. The guy hooks it up and said it won't read the car. So I hook it up and set the scanner to the correct vehicle:eyerole ... but, still says to hook it up to the vehicle. Why won't this brand new Actron Scanner find or read my Vette? Yes, it does read OBDI and II, yes, we have the correct OBDI cable connected properly, and yes, I had the key turned to on, but not started.

It still says "Connect scanner to vehicle".

So, any ideas as to what's going on here??

Thanks,

 

[Rabbit]

I would try using the car's diagnostics as outlined at this site. If this doesn't work then I can't offer any advice except to try a vette specialist. Good luck.

 

[Rabbit]

Forgot to add the link, & the edit function is not working.

http://www.corvettephotographs.com/c4vettes/index.htm

 

[SoLow]

Why won't this brand new Actron Scanner find or read my Vette? Yes, it does read OBDI and II, yes, we have the correct OBDI cable connected properly, and yes, I had the key turned to on, but not started.

It still says "Connect scanner to vehicle".

So, any ideas as to what's going on here??

Thanks,

Give Actron a call 1-800-228-7667 or email the problem to tech_support@actron.com

 

[LT4man]

Tom, maybe you could try a different auto parts store. Most of the major chains will perform the check for you. I am thinking they might use a different scanner.

Good luck and let us know what you find out.

SAVE THE WAVE!

 

[C4Tom]

Tom, maybe you could try a different auto parts store. Most of the major chains will perform the check for you. I am thinking they might use a different scanner.

OH, I didn't mention that I started by pulling into Pep Boys and they told me that they charge $80 to scan.

I left there and headed for AutoZone down the street, they had a scanner but told me that they didn't have one that read OBDI cars. I called BS... but he said, no can do.

Then I went to this brand new Advance Auto(paver and roller were just pulling off the brand new parking lot), The guy pulls out a brand new scanner and a handful of new cables for it and heads for my car.

So, I guess I need to find another store.

 

[C4Tom]

Thanks for the lead, Rabbit! I'll check it out.

 

[C4Tom]

SoLow, I didn't even think to call Actron because I didn't OWN the scanner. Thanks for the info.

 

[tigmaned]

if your 1993 vette is still a OBD-1 can't you do like us L-98 C-4 owners do and us a paper clip in the A and B port, turn the key in the on postion and read the flashes? i.e. you should see a 1-2 flash first three times and you know you computer is working right. or did some thing change between the years of the OBD-1's???????

 

[C4Tom]

Yes... just wanted the scanner to "Tell" me what was wrong.

 

[Aurora40]

Does your car have the old style OBD-I connector, or is it like the ones right before OBD-II came out where it had an OBD-II style connector but was actually an OBD-I vehicle?

If it's the OBD-II style connector, then you need a special cable for those years of cars. The normal OBD-II connector isn't the correct cable for the car.

Do you know the part number of the scanner?

 

[C4Tom]

The OBDI connector seemed to plug in normally. I did read about the change-over connector but saw that it was 1994 and 1995 model years that have those connectors.

After downloading the manual for the scanner in question, it looks like I need a power connector attached as well. Not sure though.

 

[jmccloud]

Scanner

ODB I applied to thru '05 even though that year has a II connector. Only '96 and newer has ODB II.
Your problem is almost surely bad O2 sensors. Follow the directions to ground the test lead and let the car tell you the error codes. The only thing the diagnostic tools do is convert the code to plain english, at some expense for the tool....

 

[Mike_88z51]

ODB I applied to thru '05 even though that year has a II connector. Only '96 and newer has ODB II.

I assume that you mean "OBD1 applied to thru '95" and not '05. There were some pre-96 vehicles that had OBD2. The Federal EPA mandate required all passenger vehicles sold for model year 96 and later to be OBD2 compliant. However, the law did not stop the manufacturers from selling OBD2 compliant vehicles PRIOR to '96. GM sold many OBD2 equipped vehicles earlier than 96, so that they were ready when they had to be by law. Most all 95 vettes have the OBD2 ALDL connector and are really OBD1, but a rare few really are OBD2. You have to look at the emmissions sticker to be sure. I personally have seen and scanned an OBD2 95 Vette.

Your problem is almost surely bad O2 sensors. Follow the directions to ground the test lead and let the car tell you the error codes. The only thing the diagnostic tools do is convert the code to plain english, at some expense for the tool....

The cheap ones yes. A a really good scan tool like the Ease GM OBD1 scan tool will tell you a whole lot of very useful info. You can see in real-time the actual operation of the O2 sensor(s), the throttle position sensor, the value being used for spark advance, knock counts, and MUCH more. The Ease GM OBD1 scan tool will also scan and report on the 93 and later ABS/ASR and CCM modules as well. You can save hours of scan data for tracking and pinointing intermittant drivability problems. Very useful. (Can you tell I use and sell them?)

I would tend to agree that the cause is usually the O2 sensor when you start to have a gas milegage problem as has been described, but in this case I'd definately get a second opinion concerning the inability of the Actron tool to connect with the ECM/PCM. it sounds like the Actron scan tool is unable to get serial data from the ECM via the ALDL connector. A good sign of a bad ECM is the inability to pull serial data from ALDL connector. If 2 different competent shops cannot establish communication with the ECM, it may not be the O2 sensors, but the ECM or CCM that is defective.

 

[C4Tom]

My Vette is still running with the same conditions and yet it's slightly better.

I shorted pin 'A' to pin 'G' and got the codes from the speedometer. Here is what I got:

Module 1.
H72
H74
---

Module 4.
---

Module 9.
---

Module 1.0
(at this point it sat there doing nothing so I just turned it off after over 2 minutes)

The web sites are saying there is suppose to be a system/module #7 on a 1993, which didn't come up on mine.

My Haynes only has info on a code 72 and that's a bad Neutral/Park switch???

So... what's going on here?

Thanks again people, you are a great help,

 

[Drjohn]

I left there and headed for AutoZone down the street, they had a scanner but told me that they didn't have one that read OBDI cars. I called BS... but he said, no can do.

I got the same answer today at the Zone. I wanted them to give me a read. Whoever had the car before me put in a VATS bypass. Every once in a while, the VATS enables, and I have to wait for it to start. The last time, after it started, I kept getting the SYS message all the way home. It's fine today, but I wanted to see if it had any codes that I could check.

 

[bossvette]

Actron scanners

I just bought one on Ebay but haven't had time to use it my Yellow Truck has the check engine light on
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=4639815066&rd=1&sspagename=STRK%3AMEWN%3AIT&rd=1

watch this seller he has been selling them lately and has a unit up for auction now that reads OBD2 as well as OBD1

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=4644019378&ssPageName=MERC_VIC_ReBay_Pr4_PcY_BID_IT

If I remember I will bring it to cruise-fest and maybe we can have Paul do a tech session. BTW my YT has a TPI in it.
why pay someone $80.00 when you can buy the tool for a little more?
the Actron scan tool retails for about $90.00 without cables and cartridges

 

[C4Tom]

DrJ... makes you want to slap them doesn't it?!?!

I really didn't consider shopping for a scanner on ebay, maybe I should.

Paul said he was bringing a scanner so maybe we can get some cars fixed this year!

 

[Drjohn]

DrJ... makes you want to slap them doesn't it?!?!

I really didn't consider shopping for a scanner on ebay, maybe I should.

Paul said he was bringing a scanner so maybe we can get some cars fixed this year!

My wife keeps me from slapping people all the time.

I think I may have to buy a scanner. I won't be in town for CruiseFest.

 

[Rabbit]

My Vette is still running with the same conditions and yet it's slightly better.

I shorted pin 'A' to pin 'G' and got the codes from the speedometer. Here is what I got:

Module 1.
H72
H74
---

Module 4.
---

Module 9.
---

Module 1.0
(at this point it sat there doing nothing so I just turned it off after over 2 minutes)

The web sites are saying there is suppose to be a system/module #7 on a 1993, which didn't come up on mine.

My Haynes only has info on a code 72 and that's a bad Neutral/Park switch???

So... what's going on here?

Thanks again people, you are a great help,

Module 1.0 means the CCM is waiting for instructions......