couple of questions before tranny swap

[radarwhiz]

So I have the manual pedals and clutch master cylinder in (the hard part) and the lengthened driveshaft ready. I just want to troubleshoot an issue with the old tranny before I pull it so I know it's status.
Issue:
After ~15-20 miles or so (once it's good and warm i guess) it starts not shifting past second gear. 1-2 shift is fine then it just stays in second. Usually happens under moderate to hard acceleration and doesn't matter if it's in POWER mode or not. Once it happens the first time in the day it generally continues unless it sits for a while (at least several hours). Stopping/restarting doesn't help. With selector in D and let off the throttle, RPM will drop to idle and it will coast (no engine braking), in 3 or 2 engine brakes as it should. Sometimes after very light in-town driving it will finally up-shift and clear up. The longer I drive it at a time the worse it gets till it happens every time I accelerate (mildly or hard). This began happening a few years ago before a blown engine and swap and is just the same now.
I swapped in my spare '94 TCU with no results. I am going to try swapping the TPS from wife's car as soon as she gets back. What else could I check?

Also, the engine I swapped in ('94 with ~180,000) has very low, rough idle 300 rpm or so with a/c off. Seems to have slight loss of power below ~2500 rpm. CEL comes on consistently after a few miles with 37 LH Oxygen Sensor code and clears with engine stop/restart. New O2 sensor makes no difference. I will check coils next (just unplug one at a time right?).

But not until I replace the radiator which just had this happen after getting stuck in second on the interstate (it's happened several times now) and driving at about 4000 rpm for a couple miles (doesn't seem too extreme):

Not sure why, it's never gotten too hot any of the times it's happened.

[Conn SVX]

Why do you care what the Auto tranny is doing ? I thought you were putting in a 5 speed? again . "I got the pedals in"

[radarwhiz]

I'd like to know if the auto is good or not before I offer it for sale.
I started last week and swapped the pedal assembly first because I knew that would be hardest. I've been driving the auto since then with three pedals while waiting for machine shop to finish the driveshaft. Now I am ready to swap trannies so I'm trying to find the problem before I do.

[Sean486]

As for the radiator, it probably just cracked cause it was old, not cause it ran at high rpm. All the Oem ones crack on top eventually.

[radarwhiz]

Originally Posted by Sean486

As for the radiator, it probably just cracked cause it was old, not cause it ran at high rpm. All the Oem ones crack on top eventually.

OK. Glad I have a spare

[icingdeath88]

If you have a multimeter, you should also double check that the TPS is showing the right voltage too.

[radarwhiz]

Swapped the TPS from the other car and tranny seemed to behave nicely. I'll know for sure after some more driving tomorrow.

Checked each coil on the left bank cause the code is left o2 sensor. Didn't seem like any of them were causing problem. Should I be looking for something affecting just the left side?

[1986nate]

Have you checked the fluid? Seems like its slipping once the fluid warms up.
More than likely it's had enough wear that its not going to be good for long even with new fluid. Just pull the trans apart for the parts that you might be able to sell. Front diff (Ring gear and pinion shaft) and the transfer clutch assembly if still good and scrap the rest.

[radarwhiz]

Originally Posted by 1986nate

Have you checked the fluid? Seems like its slipping once the fluid warms up.
More than likely it's had enough wear that its not going to be good for long even with new fluid. Just pull the trans apart for the parts that you might be able to sell. Front diff (Ring gear and pinion shaft) and the transfer clutch assembly if still good and scrap the rest.

Yeah fluid has always been fine. It's definitely not slipping; just not shifting right. I'll do some more driving today (with new TPS) and try to replicate the conditions under which it's malfunctioned previously. It behaved better last night but I didn't go very far.
And I put the old TPS in the other car to see if it might develop a similar problem.

[1986nate]

Originally Posted by radarwhiz

Yeah fluid has always been fine. It's definitely not slipping; just not shifting right. I'll do some more driving today (with new TPS) and try to replicate the conditions under which it's malfunctioned previously. It behaved better last night but I didn't go very far.
And I put the old TPS in the other car to see if it might develop a similar problem.

I read it a little more closely this time and makes sense. Could also check the coolant temp sensor as well. I know it can cause lock/unlock issues with the torque converter but not at the lower speeds/gears you are mentioning. I don't believe it should affect the shifting like the TPS so probably is a safe bet that is the cause of your issues. It may not even have been bad, but possibly needing adjustment. You'll find that out when you put it on your other SVX.

[radarwhiz]

I played with it some more today. Same shifting issue after the same amout of time with different TPS. I'm trying to find more exact symptoms.
It seems whatever triggers the shift gets confused and doesn't realize it's time to shift. Under hard acceleration, it's worse.
If I play with it enough, I can "force" it to upshift (reach high enough speed and work very light throttle till "gets it" and shifts).
When it does finally shift, the 2-3 shift (where the problem is) is much firmer than normal.
If I can't get it to shift at speed, after some very docile city driving for a few minutes it will begin behaving itself properly again.

[radarwhiz]

These parts have sat for quite a while and the flywheel has a bit of surface rust on it and a little bit on the friction disc as well. Would it be sufficient to just clean that off or would it need resurfaced?