99' Alero - 3500/4T45-E swap. DTCS/ECT
 

4t45-e from a 05' Grand AM GT (3.29.) The car has been sitting for about a
year and half so maybe some damage happened over that time. Mileage -
12,798 currently. It does have diff inserts so not sure if that makes a
difference.

The only code I get.

[PCM] P1810 - TFP Valve Position Switch Circuit (SES) (Old) (History) (Current) (Immature)

The IAT is NIL (bad sensor/wiring not sure yet.) Not sure if that could cause
a issue with the pressure. It really feels like it's not getting enough when it's
acting up.

This happens every other time I drive it. It doesn't seem to have a pattern.
It will happen when it's hot or cold.

It feel like a really hard shift/slightly jams into gear making a clunking like noise. Either way it's very aggressive. There is a complete lose of power above 4000 RPM and from 2500-4000RPM (under moderate acceleration --- maybe 30-50% TP) it'll jump like the clutch is engaging and disengaging. If you run it 100% it will have little to no power above 4000 RPM and hit the rev limiter and not shift until you back off the gas.

I updated the FDR to 3.29 in the VCM editor. I grabbed a stock Grand AM GT
tune and copy/pasted all the transmission specs. Disabled Abuse mode/torque
reduction.

I don't know if the original sensor was moved from the old transmission or if
it's the one that came with it. I need to check tomorrow if they are the same
sensor. If they aren't, I may pickup both and just move them in and out
and see if it helps.

Any advice would be welcomed. Thanks!

An unplugged IAT sensor, or open wiring in that circuit can cause hard shifting, and the differences in transmissions can show the other symptoms you describe. When you change over to the GrandAm GT table parameters, you may have to do a "write entire" flash to the PCM, so it can erase previously stored "learned" data.

However, thare can also be a wiring difference in the main transmission connectors. Hopefully, that's not the case.

Looked at the IAT sensor and connector. One of the wires was pulled from it.
It was loosely put back in the harness. I suspect it shorted out.

Putting the wire back securely didn't render any valid reporting. However it did
stop the intermittent code. Probably buy a new sensor and get a insert to
secure the wire in the harness.

I think it may have went bad because on my other 3500 motor, it was reporting
108. (it was around 98F and 70-80% humidity so I suspect that's correct??)
That motor only made it 15 miles so I don't have much more data than
that.

Thanks for the heads up on the IAT. I had planned to get it fixed after I got
the transmission figured out. I suspect most the issues are related.

As far as the wiring, December 09 when I got the transmission I verified the
wiring matched the Alero. I don't believe that's a issue.

However, would you happen to know how I can get the transmission
pressure/temp readings? HP doesn't appear to be able to get that info.

Have you done any exhaust work? All the rest of your symptoms are classic signs of a clogged cat. conv.

I'm not sure the state of the exhaust other than on the lift it looks flawless and
the car has 227,000 miles on it. That's saying a lot for Minnesota.

However I also did a test 8 10 mile drives. 4 with and 4 without the IAT sensor.
Without the IAT sensor it did the same shit the whole time. 3 of the 4 with it
I worked.

When it didn't work I got ...

[PCM] P1111 - Intake Air Temperature (IAT) Sensor Circuit Intermittent High Voltage (Old) (History) (Current) (Immature)

I'm guessing that's the issue. At least hoping. I'll grab a new sensor tomorrow
when I get a new water pump and find out for sure.

changed the sensor but it's report -38. Not sure where to go from here but
getting closer.

Minus 38 is the "default" (infinite resistance) reading for an unconnected sensor, so there is an open wire somewhere back to the PCM.

IAT : Clear-color connector on PCM, tan wire, pin #50.

it was but wasn't open. The guy that put the previous motor in twisted the wires and poorly taped it So after I pulled all the tape off it was rusted and just beat to shit. respliced, soldered and insulated. Now it is working like a champ.


**EDIT - fixing the IAT didn't resolve it. It did the same crap. Well at
least the IAT is fixed. 2 less codes.

On another note, I have this ANNOYING squeak that won't go away. I changed the idlers and now the water pump but it's still there. Also should the LT B1 go into the red (IE, 18-22ish @ idle?) I've never noticed that before.

Anyway thanks for all the help! you guys rule. Getting closer everyday to having the old girl fit.

uploaded a couple videos.

working properly - merging on the interstate
http://www.youtube.com/watch?v=AvHtBclI1co

off the interstate - seems a bit slow but there are still minor issues to resolve.
http://www.youtube.com/watch?v=boBSN51CeWA

not working properly but not working as bad as sometimes. It hung up a bit
at redline but not too bad.
http://www.youtube.com/watch?v=UTGKa8MjZog

if interested, here is a video from my other 3500 (the exhaust valves hit for
some reason. Not sure why, but should know soon. Need money :) not enough ATM

http://www.youtube.com/watch?v=XbzUmnL6ZxM&NR=1

lol watch out for Bad Man Jose! man, you're in trouble, plenty.
I had that record as a teenager.

I didn't realize that wasn't the original. Drunk amazon searching, lol!

A couple snaps from earlier. I forgot anti-freeze so you'll see the wrench
on the bleeder. Was waiting for my folks to bring me some lol! Pretty sexy looking.
Lolz@the flies on the intake. I live at a Ranch so plenty of horses and flies @ the
stables.

No, it was the original, mid-60s or so. nice showcase vid, too btw. These swaps are getting better all the time.

Any idea what I need to do to fix this? Not sure if it's the reason I'm having issues or not, but hopefully. It'd be nice to get in the car and have it work 100% of the time.

[PCM] P1810 - TFP Valve Position Switch Circuit (SES) (Old) (History) (Current) (Immature)




AND the complete list of codes.

[PCM] P0336 - Crankshaft Position (CKP) Sensor A Performance (SES) (Old) (History) (Current) (Immature)
[PCM] P1810 - TFP Valve Position Switch Circuit (SES) (Old) (History) (Current) (Immature)
[Brake] C1225 - LF Excessive Wheel Speed Variation (History)
[Brake] C1221 - LF Wheel Speed Sensor Input Signal is 0 (History)
[Brake] C1233 - RF Wheel Speed Circuit Open or Shorted (History) (Current)
[Brake] C1232 - LF Wheel Speed Circuit Open or Shorted (History) (Current)
[Brake] C1258 - (History)
[Brake] C1257 - (History)
[Brake] C1266 - LR Outlet Valve Solenoid Malfunction (History)
[Brake] C1265 - LR Inlet Valve Solenoid Malfunction (History)
[Brake] C1263 - RF Inlet Valve Solenoid Malfunction (History)
[Brake] C1273 - RF TCS Master Cylinder Isolation Valve Malfunction (History)
[Brake] C1293 - Code C1291 Set in Previous Ignition Cycle (History)
[Brake] C1291 - Open Brake Lamp Switch Contacts During Deceleration (History)
[Brake] U1016 - Loss of Class 2 Communication with VCM (History)
[Unknown] B2602 - (SES)
[Unknown] B2603 - (SES)
[Unknown] B2577 - (SES)
[Unknown] B3267 - (History)
[Unknown] B2965 - (History)
[Unknown] B1374 - (History)
[Unknown] B2578 - (SES)
[Unknown] B2958 - Security System Sensor Data Circuit High (History)
[Unknown] B1000 - ECU Malfunction (SES)
[Unknown] B1001 - Option Configuration Error (SES)
[Unknown] U1000 - Class 2 Communication Malfunction (History)
[Unknown] B2575 - (SES)
[Unknown] U1096 - Loss of Communications with IPC (History)
[Unknown] U1040 - Loss of Class 2 Communications with ABS (History)
[Unknown] B2587 - (SES)
[Unknown] B2588 - (SES)
[Unknown] B2648 - (SES)
[Unknown] B2585 - (SES)
[Unknown] B2600 - (SES)
[Unknown] B2601 - (SES)

I would go after those 3 codes first, many if not most of the others could be false codes (I get a lot of those, too). But there is also a Brake switch for the TCC, so it's worth investigating that area. Other than checking wire continuity first, then other sensors, no, this could be a tough one. This should be the right diagram:

I'm taking the belt off today to see if the squeak is a belt issue or something internal. Took it to a shop this AM because I'm at a lose, and he thinks it could be internal ... I'm hoping that's not the case.

After some reading on the code in question ...

http://www.fullthrottlev6.com/forums...and-code-P1810

Sounds like it's a difference between 03+ transmissions and 99-02.

Would the PCM from the 2005 GT fit the 1999? Or will the wire harness be
different? Or would I be better off looking for 2003-2004 Alero PCM and just
updating the gear ratio?

Removed the code with the VCM and did a write entire. Didn't change anything.

I don't think a 2005 PCM will work in a 1999. A 2001 or earlier GrandAm GT may work, as far as getting the car to start up and run. I tried a 1999 GT PCM in my 1999 Alero car once, and it ran after doing the relearn, but the combination had transmission symptoms like you have now.

I am using a 2001 Alero program in my 1999 Alero right now, so it may be possible for you to use a 2001 GT PCM or program in yours. If you can find a professional tuner in your area that has all the GM cars licensed, it could be possible to do a custom tune/reflash, but the PCM would have a different VIN.
In any event, you should at least get a spare PCM.

A dealership reflash is also possible, but they would charge a lot.

2002 or newer is what I'll need if I'm understanding correctly. It sounds like they changed the wire for the pressure. Maybe try looking up the wire
harness first and see if I can't just redo the connector.

It's looking like the PCM from 2002/3 should fit. Whether it will work is the question. However, I'm slowly getting the wiring double checked. I need to get the manual for the GT yet or find a diagram online. Maybe it's just a pin off or something. That'd make it easier. Otherwise, I'll try a 02/03 PCM but it looks like they have the same wiring as the 99. So I'm guessing it's going to come down to rewriting the harness to the transmission.

http://www.aleromod.com/forums/showthread.php?t=19347
try to look there for the wiring diagram, you'll be able to compare both ecu pinout I think..

You may be a noob here but I don't think you are nood in the mechanic in general ?? You seem to know what you are doing

and for the hitting valve on the 3500 what is your headgasket thickness ? And what is the pushrod lenght ? is the cam too agressive for the valve spring/pushrod combo you got ?