92polo

I had quite a bit of work done recently. ARH headers, plugs, wires, o2 sensors and hyper chip. Now I get a code 26 and the fan comes on at 158 degrees. Any ideas would be helpful. I will be checking the 3 sensors related to code 26 this week end, but the fan has me puzzled why is engages at 158 degrees instead of 228 degrees.

Thanks in advance

92polo

Sorry, brain fart, 92 LT 1 automatic

vetteoz

Have you confirm your temp gauge is accurate by another means like a thermo gun?

What is the fan setting supposed to be on the Hyper chip?

http://forums.corvetteforum.com/1565906743-post5.html
http://www.ls1lt1.com/forum/514946-post2.html

Cliff Harris

The second link is the most accurate, but still not right. If there is a quad driver fault the ECM/PCM will set error code 26. It does this if it detects too much current in one of the 4 outputs. Generally that means that something is shorted, either a relay or solenoid or the wiring. Unfortunately it doesn't tell you which one is bad.

The first step is to determine which 4 things are controlled by that quad driver. Then investigate those guys (and the wiring).

Feel lucky. Earlier cars didn't even have this error code available.

92polo

Thanks for the input. I was told today the fan setting on the hyper chip is set at 160 degrees, so I guess that is ok. I will be testing the solenoids tomorrow and hope I can diagnose the problem. Today the AC went out again and the buttons started flashing. The AC was also just reset a week ago while in the shop. Any ideas or could this also be related to the code 26?

vetteoz

Have you changed the thermo stat to reflect the new fan operating temps

92polo

I found the problem. I disconnected the battery and changed the 2 solenoids under the fuel rail covers and still had the service engine light come on but not until the fan kicked in at 190 degrees. So I started looking at every connection under the hood. Boy do I feel stupid. I found a connection to something located under the ASR on the drivers side that the mechanic who installed the headers did not reconnect. As soon as I plugged it in and started the car the AC works and the service engine light never came back on. I guess you have to check everything any time you have someone work on the car for you. Thanks for everyone's help.

pkincy

It is the mechanic that should feel stupid. Glad you got it figured out.