I've been lurking on these forums for the past few days trying to find someone with the exact same problem as me, no luck. From what I have read, it sounds like my truck is in Limp mode.

I recently purchased this truck for a steal ($300), it had been sitting in a barn for two years, first thing I did is drain the fuel and put some fresh fuel in it with a bottle of Lucas fuel treatment. For the first 20 minutes of running the motor it ran like crap, when I took it home, I changed the oil and put oil treatment in.

First issue, it seems to be starting off in third gear, which from what I've read sounds like limp mode. When I try to go through the gears, first gear does nothing, second gear is slow as molasses like it's actually engaging in third. I put it in drive, I get the same thing as when I put it in second. The strangest thing is no check engine light is coming on. What are the steps I should take to further troubleshoot this issue? Another question I have is if the gears are screwed, is it possible to replace the gears only or do I have to replace the whole transmission?

Second issue, sometimes when driving it randomly stalls out, I believe it might be the injectors, is there a way to tell which injectors may be out? The only other thing it could be is the battery that is in it, a car battery with 500 CCA, what is the mininimum and recommended CCA for a battery for this truck, it does not have the owner's manual and I am having hell finding it online. If anyone has a link to download it, I would greatly appreciate it.

Thanks.

Edit: This is the 5.2 V8 automatic with, I believe, the 46re.

 

If your battery is weak, (as in, poor condition) you will get some odd running problems out of it.

Does it stall at stops and such? if it does, just pull the throttle body, and give it a good cleaning. Remove the IAC motor on the back of the TB, and clean those passages really well.

Test the TPS as well. If should sweep smoothly from somewhat less than one volt, to greater than 3.5 at WOT. If the reading bounces around, replace it.

Check your trans fluid. (in neutral, checking it in park will be inaccurate.) Also, see what it looks like..... You might be able to convince it to work correctly by disconnecting the battery for a few minutes, to reset the ECM. If that doesn't help, time to drop the pan, and see what ya got.

 

I will test the battery disconnect right now and let you know what it does.

 

I tried to reset the ECM by leaving the negative on the battery unplugged for an hour, it did not solve any of my issues.

Transmission fluid is in the safe zone.

Now it is seeming that first is out, I can manually shift from second, but when I put it in first, nothing.

As for the stalling issue, it seems like when it's in third gear and hits around 2000 RPMS, the RPMs drop to and keep flucuating between 750 and 1500, then the oil pressure light comes on, and the gauge reads 0, then it dies, once I start it back up the oil pressure goes to 20 when driving and 0 during idle.

 

Hhhmmm......

If you do indeed have a 46RE... (96 or newer) Try unplugging the 8? pin connector on the drivers side of the trans, just behind the linkages. This will disable ALL automatic function.

Manually shift the trans thru the gears, see if you actually have them. If any are 'missing', it's time for a rebuild.