5.7 TBI running rich with trans issues

[powellbr5591]

Hi all, this is my first post on here, I own a 1993 k1500 extended cab short bed stepside I got for a graduation gift last year and am having problems with it. I have the 5.7 TBI and it's running rich and to boot the tranny isn't up shifting out of first or it's stuck in limp mode. I have no idea what could be the problem with the trans, I read somewhere, don't remember where, but a guy was having issues with a custom ordered truck with a 4wd 4l80e and the 5.7, he unplugged some sensor on the back of the transfer case, IIRC it was one of the speedo sensors, and it shifted fine, but he still took it to a shop and the tech said that in that kind of condition the case would have grenaded itself in another week or two because the line pressure skyrockets and the clutches were shot in his situation, causing it not to shift till the pressure skyrocketed like it did.

I asked a friend of mine who's good with older trucks like mine and he said to unbolt the battery overnight because it could be a TCM issue, unfortunately I don't have the wrench to remove the but because it's a side post batter and I don't want to lose it so I'm avoiding doing it with channel locks. Does anyone have any ideas on why it's running rich? One idea of mine is that the coil is on it's way out but I don't have one to replace it, it's an HEI and I have a canister coil on hand, no tools to convert it over from one to the other, my uncle who has a single cab regular bed GMC 3/4 ton with a 454 and he said that there are two screws on the inside of the distributor cap that can go bad and I suggested that one of the two is out and the other might be on its way also.

Sorry for the long post, I can tend to ramble some times. Thanks in advance for the information in advance.

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[sntrym]

TBI can run rich for a variety of reasons, but I would start with the coolant temp sensor. This is located on the top of the intake manifold next to the thermostat housing. You can test the CTS with a multimeter using the directions here: http://67-72chevytrucks.com/vboard/showthread.php?t=425788.

The transmission issue could be a wiring issue or mechanical failure. First, check the fluid. If it's low, it won't shift. If the fluid is ok (bright red, level is good, doesn't smell burnt), see if you can manually shift from 1 to 2 to 3. You may have a bad shift solenoid, or it might be time for a rebuild. Limp mode on those is manual shift from 1 to 3 IIRC. You probably have a 4L60E, not the 80 unless you have the HD package.

The side posts on the battery are 8mm btw. Don't use pliers.

 

[powellbr5591]

TBI can run rich for a variety of reasons, but I would start with the coolant temp sensor. This is located on the top of the intake manifold next to the thermostat housing. You can test the CTS with a multimeter using the directions here: http://67-72chevytrucks.com/vboard/showthread.php?t=425788.

The transmission issue could be a wiring issue or mechanical failure. First, check the fluid. If it's low, it won't shift. If the fluid is ok (bright red, level is good, doesn't smell burnt), see if you can manually shift from 1 to 2 to 3. You may have a bad shift solenoid, or it might be time for a rebuild. Limp mode on those is manual shift from 1 to 3 IIRC. You probably have a 4L60E, not the 80 unless you have the HD package.

The side posts on the battery are 8mm btw. Don't use pliers.

OK, that helps a lot, either yesterday or the day before I decided to look up what each of the RPOs meant and supposedly it's a heavy duty, it manually shifts fine through 1-3, although I don't have any service history on it and I know not everything's original because it's supposed to be a fleetside but it's got a sportside bed and an overhead center console off like an '02

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[powellbr5591]

So then if the cts is on the water neck what's the sensor sticking out of the driver side head?

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[powellbr5591]

So when I was driving to the store and back today I tries manually shifting it today and it was working fine, I didn't notice a 1-2 shift with shifting it manually though, almost wish I had a button for OD though

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[sntrym]

The sensor in the head is the for gauge.