Top 10 1996 GMC Jimmy Questions & Answers

check the hoses connected to the vacuum advance ball, it has probably begun to decompose...

I have a Dodge Charger 06 model and the gear wont move from Park to reverse. everything else works as far as gas, brake light, etc but my gear wont shift can i get soem help

The knocking or ticking is going to determine if it is in the top end, lifters, push-rod or rocker arm issue or the bottom end that would include pistons or bearings.
If it is a ticking noise, it will more than likely be a valve train issue.
If a knocking noise, piston or crankshaft related problem.

Attached is a web site that you can listen to a piston slap which is a known issue for your 4.3.
Listen to the noise and see if it sounds similar to your problem. A piston slap will generally sound as though it is coming from the central area of the engine.
Listen to the recording and let me know.
Regards,

The a/c clutch is attached to the front of your a/c compressor. It is the part that your serpentine belt runs on. It is either engaged or not based on the demand of the a/c system. It will not run if it senses low pressure in the freon supply line so you might try having the system checked for proper fill before replacing the clutch.

IF the abs dash light is on and if the speedometer is sluggish or not working at all, it is probably a bad speed sensor on the transmission. and easy fix under $40 for the part. Mine was stuck in second gear for a while then worked then it stuck in first gear and i had the CHECK ENGINE light on.

You'll need to start bleeding the brake system at the Master cylinder to determine where the problem lies.

The lines coming out of the master cylinder will need to be loosened & bled there, initially you can just do the back ones to identify the problem, but once fixed, the system will have to be bled from the Master cylinder first, then the farthest wheel from it, then next farthest, then next, until you do the drivers wheel last.

This method of bleeding the brakes prevents air from crossing from one line to another, causing air to be left in the system.

Back to bleeding the rear brakes first: As someone pumps up the brake pressure, making sure the resivoir stays full, with the cap on between bleeding, and have the person pressing the pedal to do these thngs.
1. Always move the pedal slowly, pressing and releasing.
2. Never release the pressure on the pedal after bleeding a brake, until the line is tightened, then release slowly to prevent air from getting into the fluid.

You should of course get fluid at the master cylinder when you bleed it (or just replace it), then you'll need to bleed the line at the right rear wheel (first) a few times to get fluid if it's been leaking, then the left rear wheel. If you get pressure but no fluid to the rear and the master cyliinder did have pressure released when you bled it, there is either a restriction in the line itself, or the porportioning valve could be damaged. (unusual for the valve to go bad actually, inspect lines for damage such as being pinched if you're getting pressure but no fluid.

Final test if it hasn't been resolved-remove lines at porportioning valve & make sure fluid is leaving/entering there as it should. If you find it defective, a good replacement can come from a salvage yard, or you can buy them new.

Brake fluid on the floorboard under the dash near the brake pedal=bad Master Cylinder.

good luck

P0446 Evaporative Emission System Vent Control Circuit.
The following are descriptions of all Evaporative possible codes:

P0441 Evaporative Emission System Incorrect Purge Flow
P0442 Evaporative Emission System Leak Detected (small leak)
P0443 Evaporative Emission System Purge Control Valve Circuit
P0444 Evaporative Emission System Purge Control Valve Circuit Open
P0445 Evaporative Emission System Purge Control Valve Circuit Shorted
P0446 Evaporative Emission System Vent Control Circuit
P0447 Evaporative Emission System Vent Control Circuit Open
P0448 Evaporative Emission System Vent Control Circuit Shorted
P0449 Evaporative Emission System Vent Valve/Solenoid Circuit
P0450 Evaporative Emission System Pressure Sensor/Switch
P0451 Evaporative Emission System Pressure Sensor/Switch Range/Performance
P0452 Evaporative Emission System Pressure Sensor/Switch Low
P0453 Evaporative Emission System Pressure Sensor/Switch High
P0454 Evaporative Emission System Pressure Sensor/Switch Intermittent
P0455 Evaporative Emission System Leak Detected (large leak)
P0456 Evaporative Emission System Leak Detected (very small leak)
P0457 Evaporative Emission System Leak Detected (fuel cap loose/off)
P0458 Evaporative Emission System Purge Control Valve Circuit Low
P0459 Evaporative Emission System Purge Control Valve Circuit High
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At least the cap isn't loose for the gas tank.

I would clear the code with an OBD-II Scanner 'erase code' button, and see how long it takes for it to come back.

Hi, It may be in LIMP mode.

What is "limp-home mode" ? This is a fault mode in which the transmission either loses electrical power or the PCM deactivates all of the electronics. The transmission will default to max line pressure. The driver will have Reverse and 3rd, with manual 2nd available by putting the gearshift in 2 or 1 (doesn't matter). 1st, 4th, and TCC lockup will not be available. It will not hurt the car to drive it like this for short periods, but use manual 2nd to get the car moving, and be aware that the trans will generate more heat than normal while operating in limp-home mode due to increased torque converter slippage during 2nd gear starts and no lockup in 3rd gear.

Common failures on 4L60E, symptom any possible repair:

Trans shifts into gear harshly, car feels sluggish off the line, No 1st, 4th or TCC lockup available, Manual 2nd, 3rd and Reverse are only available gears, CEL is on: Transmission is either in limp-home mode or has lost electrical power. If there are lots of error codes in the PCM, check the under-hood fuse that powers the transmission, and if it pops again, look for a short in that circuit like an O2 sensor harness touching exhaust. Otherwise, check PCM codes for a particular fault in the transmission causing the PCM to put it in limp-home mode.

No 1st or 4th available; trans shifts 2nd to 3rd by itself in D or OD and locks the converter :ShiftA solenoid failed. Easy fix in the pan. Or a wiring problem from PCM to trans.. or PCM.

Car goes into gear but feels very sluggish like the brakes are dragging, but it will roll easily (starts out in 4th gear), you manually shift to 2 to get it moving, once it's moving you put it back in OD and the car shifts 3rd to 4th on its own and locks the converter at the appropriate time: ShiftB solenoid failed: Easy fix in the pan. Or a wiring problem from PCM to trans.. or PCM.

Trans seems noisy when moving in 1st and Reverse, noise goes away instantly if you shift to N or the trans goes into 3rd gear: Reaction planetary is worn out due to high miles or insufficient lubrication. Not a critical failure, but not a good sign either. R&R sooner rather than later.

3rd gear starts, can manually shift through all gears. When car has been turned off for a bit, then back on it will run normally.: VSS dropoff w/ Hi-stall converter. The rpms are too high, but VSS is showing no movement. Happens after a tire burning take-off. Doesn't store a code, will not throw a CEL (I've heard that it will store a code if it happens 3 or more times). Cure: Reprogram PCM for VSS dropoff -- PCMforLess knows about it.

If you can get the Jimmy for no more then $500.00 and the engine sounds good and body is good, you may want to invest in the repair of the jimmy. Also note that to have a close look at the fuel line along the frame on the drivers side just by the back doors, the line is know to corroded there on all the SUV's

You can try disconnecting the battery cable then try to openit with the key There is an electrical switch they call it the actuator its inside the tailgate trim panaland easy to replace This sounds likely to be what your problem is the switch may be shorted and in lock mode all the time

The fuel pressure regulator is mounted inside the intake plenum. You'll have to take the top half of the intake plenum off and replace the fuel injection spider.