Manager Forum

FEELS LIKE TCC SOLENOID ISSUE. SLIPS IN AND OUT OF 4TH GEAR AND 55 MPH. ACCLERATE AND WORKS FINE. REPLACED TCC SOLENOID AND TCC CONTROL SOLENOID STILL HAVE SAME PROBLEMS, WOULD GREATLY APRRECIATE ANY AND ALL IDEAS

How many miles on it and what is the scanner telling you? This vintage transmission has issues with valve body's cracking and causing this. Another thing is if the vehicle isn't running well it will kick in and out as well. I've seen fuel supply issues causing this. With the scanner watch and see if it's being commanded on and off. If it starts kicking in and out with the on command showing you probably need to get a reman or you can try a valve body. If it's commanding off and on it's probably an engine performance issue.

customer finally brought vehicle back, did as suggested, tcc solenoid is commanded on, when vehicle starts bucking it goes off but at same time I have misfire in cylinders 1,3,5 and mostly number cylinder 7. This vehicle has recently had complete tune up and new distributor put in else ware, I checked base timing and found distributor two teeth off. corrected still have same problem. Also I feel I need to mention this vehicle has a 345,000 miles on it.

Well the computer is working kicking it out of overdrive. Issue could lie in the misfire. After codes were cleared and vehicle driven were they back in pending? The key here is what was it doing before it was tuned? You may still be dealing with an issue that was present prior to the tune up. A good chat with the customer may be needed. Could be a sloppy timing chain or partially restricted injectors.

I'm betting on a bad timing chain, but did you do a crank relearn on it after re-indexing?

I DID CAM AND CRANK RELEARN WHEN IT RESET DISTRIBUTOR. THERE ARE NO CODES FOR MISFIRE. PULLED TIMING COVER AND CHECKED CHAIN. FOUND CHAIN WITH EXCESSIVE PLAY AND MARK ON CRANK SENSOR FROM CHAIN. ALSO DID COMPRESSION CHECK ALL CYLINDERS AD 120 PSI. REPLACED TIMING CHAIN AND CRANK SENSOR. STILL HAVE SAME PROBLEM. DROVE AND RESCANNED. TCC SOLENOID WORKING, STILL HAVE MISFIRES FROM 1,3,5 AND 7, MAINLY CYLINDER NO. 7. STILL SHOWING NO CODES, I AM AT A LOSS. NEVER SEEN A MISS FIRE ON CHEVY SMALL BLOCK WHERE THERE MISFIRING ONLY ON ONE BANK.

Man I just had written a long as per Steven reply and my system went bonkers. Probably due to my fingers being like toes and, well what ever. I had a shorted 02 do exactly that. The 02 avoided discovery since it read fine most of the time. Went through a bunch of issues trying to resolve this exact issue. Won't get into the step by step by step diagnostics but eventually we found the 02 faulty. Only happened as you described and all my diagnostic servers hadn't any mention of it. It was on the right bank, would kill all cylinders and pcm would try to balance out the engine so it would run somewhat smooth. I love it when pcm's do this and it throws out the good old boy tech's basic diagnostic skills and forces me to rely on a screen. I have my own thought as to why this was happening but since truck ran great after that I was happy. The 02 readings weren't that bad nor were they causing code issues. When the engine flattened out the readings would scatter just for a second or two. We replaced all of them. The ones on the right because it solved the issue and the ones on the left because I didn't want to see it return because they failed. I looked the vehicle up and it was a bit older but everything else you supplied fit to a t.

By the way, using caps is apparently yelling and to some it may be taken the wrong way. I use caps all the time when writing orders and such and have looked up after responding to a post and see all caps. Many years ago I was called on it and now I look all the time. I'm a board watcher, not a screen watcher.

The last post you made hade more information in it and that's what kicked a drawer loose and brought that memory of "I never want to even think about this again" out of hiding. I'm remembering all the frustration now. Questioning my tech's diagnostic ability, convinced he missed something obvious, my frustration so obvious he was taking it personally, and the resolution dumbfounding me and me looking deeper into it trying to discover if we missed something in our diagnostic flow.

Yea i have had a lot of oxgen sensor front one on the diver side being bad. Would make a miss on that side with 7 being the worse. I will bet then i have done 20 this year... let us know ....

CUSTOMER BROUGHT TRUCK BACK, INSTALLED NEW OXYGEN SENSORS, PROBLEM SOLVED, THANKS FOR EVERYBODYS HELP, VERY MUCH APPRECIATED