Eighty7camarokid

iTrader: (4)

I had my transmission rebuilt by a shop this week. All went well, except the transmission will not shift into 3rd. It just revs out. This is the first time the mechanic said he has ever seen this. Upon installing the transmission, they noticed that the wiring harness going to the transmission had been hacked and spliced. On monday, they are going to replace the internal transmission wiring harness. If that doesnt work, any ideas? The computer has power and the harness was rewired up correctly. Its a 98 Z-28 with the 4L60e BTW. lol

FLT

iTrader: (1)

I'm not sure as to why your guy wants to replace the internal harness if the external one is in poor shape. I would be questioning his reasoning for this. I myself would put tranX box on the vehicle to monitor what the computer and the trans are really doing first. With this tool you can also bypass the vehicles computer and use it instead to command the transmission. By doing this the guy should be able to isolate the problem. I myself think that he must have a problem in the trans and is trowing parts at it. Good luck and let us know what you find. Vince

Eighty7camarokid

iTrader: (4)

Hes doing the internal wiring harness for free. I will post more info on monday.

Gilbert@Ace Racing

Be sure to get back to us on this one.

If the electrical connector was not plugged in and the car was started and the tranny placed in to any forward gear range the unit would achieve 3rd gear mechanically. Meaning, it is most likely not an electrical issue at all.

It only makes sense that the problem lies with the build in my opinion.

g

performabuilt

iTrader: (25)

When you say it just revs out do you mean it just stays in second untill it hits the rev limiter or that it suddendly feels like it just went into neutral

Eighty7camarokid

iTrader: (4)

I did not get to test the car myself, I work and am a full time student. From what I was told, it does not want to shift into third at all. Before I had the tranny rebuilt, it would shift out of second and into a neutral.

Gilbert@Ace Racing

So they described a similar condition to you after the rebuild? Sounds like it. I would think that they did not find the source of the problem during the build, just installed new parts after dissasembly and cleaning. But, that's just an opinion.

g

Eighty7camarokid

iTrader: (4)

The internal wiring harness is the ONLY thing that was reused. When that gets replaced on monday, and IF it still has the same problems, suggestions? I have had this car since the first week of August and have not been able to drive it since I bought it. I am getting really anxious.

performabuilt

iTrader: (25)

Ok sounds like two different problems in the same area, First thing to do is to determine if the shift it actually being comanded, I do this two ways one with a scanner and two by attaching two leds to the light green wire and the yellow wire at trans harness, You see if the comand is taking place by watching the grounds to the shift solenoids, (We have a box for this but you can make one with a few dollars in parts from radio shack) Once thats determined to be ok or not decides where to go from there, Its and important test since I have seen the PCM say the shift was comanded yet the 2-3 solenoid did not actually loose its gound (bad PCM) . Once that has been determined to be ok. Next would be to disconnect the harness from the trans and drive and see if the car is indeed in third gear as it should be by comparing the RPMS in manual second to the RPMS in manual 3rd. The RPM at a given speed in d should be less that the rpms at the same speed in 2nd.(Note if the RPM in D are higher than the RPM in manul second The 3-4 clutch is not applying and the problem is internal with the 3-4 clutch) If its determined the RPM are the same I would look at the valve body next. Check that the feed holes to the solenoids were not enlarged in the valve body plate and that the 2-3 shift valve is not stuck , It is hydraulically moved and has no spring like the 1-2 to help it along and I have seen both of these things cause a no 2-3.
Hope this info helps and feel free to holler if you need any more.

Gilbert@Ace Racing

I dunno Frank. For a smart guy like you that might seem all well and good. But for the average consumer / enthusiast who just spent big bucks having his transmission overhauled it might be a little too much work.

But hey, what do I know. I am sure that the OP is in good hands and they will handle it for him.

g

performabuilt

iTrader: (25)

Just giving some ideas. Actually have had a few people do test like these to solve fnd issues. I have learned there are some very tech savy individuals on this site. But anyway it was just some information either for him to use or perhaps the shop. There are many shops out there who arent so tech savy I am sure you allreay know that if you have spoken to as many as I have over the years. But I agree they should make it right for him and hopefully they will.

Eighty7camarokid

iTrader: (4)

They took the tranny out again, rewired about 5 spliced wires, and we now have all gears. But now the damn thing wont start now....I hate F-Bodies lol.

Gilbert@Ace Racing

Cool! I am curious to know what they spliced... but I suppose we'll not ever know that one.

If they got the tranny up and running, I'm sure they'll get the starter up as well.

g

Eighty7camarokid

iTrader: (4)

Oh, its not the starter. It will crank and crank and crank but will not fire. I can hear the fuel pump prime cause its been replaced before with the "cut the hole" mod. Argh, the benefit of a cheap LS1 I guess....