Help?

[paul]

Hello again guys,
I know I'm new here and am being a pain the behined but can I assume that with no response to my fault code request (DTC 26 and 28 - '93 T/A Lt1 ) no-one knows for sure what my problems are.
You see I live in England so I can't take it to my local garage as they have no reference material for my car.
I have only had the car a week and am hoping that the fountain of knowledge you have here may help me enjoy my car for years to come.

[Black97]

Welcome to the board. Just be patient and wait for a while, if somebody knows they will post an answer.

Here's what I found doing a search on Google.

http://autorepair.about.com/library/...l-dtcs-36a.htm

Hopefully based on that somebody can help you better.

Rene

[paul]

Thank you

Many thanks Black97 for replying.
I must apologise to everyone on this forum, I should really have introduced myself properly rather than launch into a request.
Anyway I shall learn from my mistake and will patiently await any further advice.
On the subject of the codes I think now the code28 has been answered( Where is the Tranny pressure switch thing? ), but the code26 remains a mystery.
I hope I will be able to contribute in the future even if it's about F-bodies in the South of England.

[TraceZ]

Re: Thank you

Originally posted by paul
Many thanks Black97 for replying.
I must apologise to everyone on this forum, I should really have introduced myself properly rather than launch into a request.
Anyway I shall learn from my mistake and will patiently await any further advice.
On the subject of the codes I think now the code28 has been answered( Where is the Tranny pressure switch thing? ), but the code26 remains a mystery.
I hope I will be able to contribute in the future even if it's about F-bodies in the South of England.

Here is some info on your code 26
Code 26 - quad driver fault

If I'm understanding it correctly, it seema you may have a sensor or solonoid dead shorted. You'll need to replace the item in question, and then possible replace the ECM if the fault does not go away.

Possibly one of your "gear switch circuits" as mentioned in the chart above is shorted? Does your transmission shift properly?

[paul]

Thanks for your reply.
Firstly my gearbox does seem to shift perfectly( that's if its normal to spin the tyres when it changes gear under full throttle).
Secondly - oddly the 'service engine' light doesn't come on when the engine is cold but waits a few minutes before it illuminates.

[Injuneer]

The 93 "Quad Driver" codes are a mystery to many of us.... I've literally "written the book" on scanning 4th Gen LT1's, for the 94 and up models, but after 5 years, I still don't know for certain what the 93 QDM codes mean. I have speculated that the 93 QDM circuit trouble codes are similar in function to the 94 and later DTC codes.

That would mean:

DTC 26 = QDM #1 = EEC canister purge solenoid
DTC 27 = QDM #2 = EGR solenoid
DTC 28 = QDM #3 = Tranny range pressure swithc assembly.

In spite of numerous requests on numerous boards, I have never had a 93 owner get back to me and either verify or disprove that assumption.

[paul]

Thank you Injuneer, I was beginning to come up with the same theory as my Chilton manual shows the '94 codes almost identical to the '93.
Before I replace the purge solenoid is there anyway of testing it as I cannot find a method in the manual.