97 Rocker Valve Adjustment
#131
Junior Member
Join Date: May 2017
Location: North Dakota
Posts: 338

OK I bought the 1995 GMC Jimmy 4.3 262CBI Vortec. The bad :
1. Reverse is out, it jumps into gear but doesn't move backwards.
2. Bad acceleration, I can hold gas pedal to the floor and go no where, until I pump it then it will slowly gain acceleration. Jumps thru gears with no problem. Took it on the highway home last night, got several miles @ 55mph and the passengers side under the truck started smoking. Jumped off the highway to main streets @ 25-35mph, and it stopped smoking and still continued to shift fine, when it could due to slow acceralation. Idles @ 500-700 rpms. Sometimes "pops" when I try to accelerate it. As I'm accelerated, and I'm coming to a stop, I can hear a rattling noise as I stop.
Those are my 2 only problems. I'm guessing fuel filter replacement, transmission filter replacement, new tranny fluid , new spark plugs, and an oil change? Truck has 190k on it. Engine fires up and idles fine, until I try to accelerate and drive. Drivable, just takes some pumps to get it going.
1. Reverse is out, it jumps into gear but doesn't move backwards.
2. Bad acceleration, I can hold gas pedal to the floor and go no where, until I pump it then it will slowly gain acceleration. Jumps thru gears with no problem. Took it on the highway home last night, got several miles @ 55mph and the passengers side under the truck started smoking. Jumped off the highway to main streets @ 25-35mph, and it stopped smoking and still continued to shift fine, when it could due to slow acceralation. Idles @ 500-700 rpms. Sometimes "pops" when I try to accelerate it. As I'm accelerated, and I'm coming to a stop, I can hear a rattling noise as I stop.
Those are my 2 only problems. I'm guessing fuel filter replacement, transmission filter replacement, new tranny fluid , new spark plugs, and an oil change? Truck has 190k on it. Engine fires up and idles fine, until I try to accelerate and drive. Drivable, just takes some pumps to get it going.
#132
Starting Member
Thread Starter
Join Date: Mar 2017
Location: Tulsa, OK
Posts: 220

Automatic transmission loosing a gear usually means a rebuild or replacement is in your future. You can try changing the fluid and filter but dont be surprised if there is no difference. It could be alot of things causing the bad acceleration. Where was the smoke coming from? Front tire, Under truck, engine compartment? Does the blazer roll fine in neutral?
#136
Starting Member
Thread Starter
Join Date: Mar 2017
Location: Tulsa, OK
Posts: 220

Also why is it hard to push when it's in neutral without the E brake?
#137
Junior Member
Join Date: May 2017
Location: North Dakota
Posts: 338

Unless you have a Infrared thermometer or temp gun i would suggest taking it to an exhaust shop and see if they will test the cat for you. The simple way to test the cat is to measure the temp of the exhaust pipe just before and just after the Cat. If the temperature after the cat is hotter than before the cat it is working correctly but if the pre cat temps are the same or higher than the post cat temps then the Cat is probably bad.
#138
Junior Member
Join Date: May 2017
Location: North Dakota
Posts: 338

How can I test it or remove it? A friend of mine said I don't even need it, and O'Reilly has pipe to put in place of the cat and not cause it to be loud? Do I have to have it on or can I drive without it?
Also why is it hard to push when it's in neutral without the E brake?
Also why is it hard to push when it's in neutral without the E brake?
In the previous post you said it wasnt hard to push in neutral. If it is hard to push, i would try jacking the front end off the ground and spinning each wheel to make sure they turn freely. Then chock or block the front tires, jack up the back end and put it in neutral with the e-brake off to make sure the rear spins freely.
#139
Starting Member
Thread Starter
Join Date: Mar 2017
Location: Tulsa, OK
Posts: 220

If you take the cat off and just replace it with a pipe, it will throw a check engine light for the emissions system.
In the previous post you said it wasnt hard to push in neutral. If it is hard to push, i would try jacking the front end off the ground and spinning each wheel to make sure they turn freely. Then chock or block the front tires, jack up the back end and put it in neutral with the e-brake off to make sure the rear spins freely.
In the previous post you said it wasnt hard to push in neutral. If it is hard to push, i would try jacking the front end off the ground and spinning each wheel to make sure they turn freely. Then chock or block the front tires, jack up the back end and put it in neutral with the e-brake off to make sure the rear spins freely.
#140
Junior Member
Join Date: May 2017
Location: North Dakota
Posts: 338

Depends on which tire. If it is one of the front it could be a collapsed brake hose or stuck brake caliper dragging. If it is one of the back it will depend if you have disk or drum brakes. Drum brakes could be collapsed brake hose, just out of adjustment or e-brake not releasing completely. and disk brakes could be stuck caliper or collapsed brake hose or e-brake not releasing completely.
By spin freely i mean it is not hard to turn by hand.
If it was just one of the front brakes dragging though it would pull real hard to one side while you are driving. Is the truck pulling to either side when you drive it?





