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Engine Runs, loss of power though?

saybye

NAXJA Forum User
Location
Soddy Daisy TN
Just bought this thing last night, brought it home parked it, it ran fine. I go to get in to today to pull it the the garage and it seems like its lost a ton of power, like it doesnt want to accelerate. The best way I can explain it is pulling an ebrake up at a stop then trying to accelerate. Either that or its like its taking off in a high gear maybe? I can pull the shifter (auto) down to the lowest gear and it feels like it has the correct power with the shifter pulled all the way back. Any idea's?
 
haha my bad its a 93 sport 2 door auto.

apparently my searching sucks and I was describing it the wrong but right way which makes no sense I know... anyways I came upon this and it sounds like this way be a path to follow.

http://www.naxja.org/forum/showthread.php?t=987463

After reading the above thread, can we read our CEL without a reader? I know some vehicles you can turn them on off a certain amount of times, hold something down and the CEL will flash a code. # of flashes = a code.
 
If either fuse number 3 in the PDC goes out or you have ground issues, the automatic transmission becomes a manual shift transmission.

New to me XJ I always do a compressions test.

Then Cruisers ground refreshing check list.

Inspect the harnesses and wiring in the engine compartment and underneath.

Check all the vacuum lines.

There is more, but I've found the general approach beats trying to chase down specific issues. Many issues resolve themselves after doing Cruisers checklist. Motor basics (fuel, air, spark and compression) have to be good before the power train controls can function properly. No telling what kind of problems the last owner caused or past mechanics screwed up. Start with the basics.
 
If either fuse number 3 in the PDC goes out or you have ground issues, the automatic transmission becomes a manual shift transmission.

New to me XJ I always do a compressions test.

Then Cruisers ground refreshing check list.

Inspect the harnesses and wiring in the engine compartment and underneath.

Check all the vacuum lines.

There is more, but I've found the general approach beats trying to chase down specific issues. Many issues resolve themselves after doing Cruisers checklist. Motor basics (fuel, air, spark and compression) have to be good before the power train controls can function properly. No telling what kind of problems the last owner caused or past mechanics screwed up. Start with the basics.

Interesting, seems like I MAYBE removed fuse 3 last night and placed it in the illumination point because that fuse was blown. I cant remember exactly, but I may have test drove it with no fuse in 3. I know I did put the fuse back when I got home, then drove it again, still had the same issue. Would I need to disconnect the battery and allow the computer to clear before this would correct itself?
 
Fuse 3 is basically the on/off switch for the TCU (transmission control unit) which is separate from the PCM (powertrain control module/main motor management computer).

Check the easy stuff first, you don't want to do brain surgery for the hiccups.

Yu may have blown fuse 3 when you put it in the illumination slot and then put a blown fuse back into the tranny slot.
 
Fuse 3 is basically the on/off switch for the TCU (transmission control unit) which is separate from the PCM (powertrain control module/main motor management computer).

Check the easy stuff first, you don't want to do brain surgery for the hiccups.

Yu may have blown fuse 3 when you put it in the illumination slot and then put a blown fuse back into the tranny slot.

My owners manual said 3 was for power windows, my jeeps manual locks and windows, which makes no sense, I just though it was an empty slot. This will be my starting point tonight...
 
The fuse block is on the inside of the cab, above and near your left foot. The PDC is in the engine compartment near the battery. The TCU fuse is in the PDC. At least it should be, they moved many of the fuses from earlier years from the fuse bock to the PDC, I'm almost sure the Trans fuse is in the PDC for your year, but just in case look for a spot marked trans in the fuse block. Pre 91 and the fuse was in the harness behind the glove box.

As a side note, in my experience you can't always believe your owners manual or the inside the lid diagram for your PDC. Use them as a guide, not as an absolute map.

It may be something else, but the fuses are always a good place to start. Then you can try to figure out why the fuse blew. Been my experience when the solenoids go, you loose multiple gears and/or get the wrong gears.

A bad ground will shut down your TCU just like a blown fuse will. You can still manually shift, but it won't work as a true automatic.

My advice is to troubleshoot from simple to complicated, then on to exotic.
 
The fuse block is on the inside of the cab, above and near your left foot. The PDC is in the engine compartment near the battery. The TCU fuse is in the PDC. At least it should be, they moved many of the fuses from earlier years from the fuse bock to the PDC, I'm almost sure the Trans fuse is in the PDC for your year, but just in case look for a spot marked trans in the fuse block. Pre 91 and the fuse was in the harness behind the glove box.

As a side note, in my experience you can't always believe your owners manual or the inside the lid diagram for your PDC. Use them as a guide, not as an absolute map.

It may be something else, but the fuses are always a good place to start. Then you can try to figure out why the fuse blew. Been my experience when the solenoids go, you loose multiple gears and/or get the wrong gears.

A bad ground will shut down your TCU just like a blown fuse will. You can still manually shift, but it won't work as a true automatic.

My advice is to troubleshoot from simple to complicated, then on to exotic.

Ok Im following you now, I check when I get home and post. Thanks
 
We'll somehow the tcu got unplugged. So everything is good on that end for now, thanks so much for all the help, learn a TON even tho it was something so simple
 
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