91 chevy g20 sudden proble help!!!

[dssdj2007]

Hey guys its been a while since ive been on here with a problem, well let me start of by saying i have a 91 chevy g20 never had any major problems with this van for the exception of a bad ujoint. Just last week out of nowhere it started driving really wierd when i step on the gas it like idle wiered and then eventually will drive ok but when you get to lower speeds it does the same thing on the freeway it drives fine, also it has a really bad exhaust smell inside it just started like that i had the mufller off for a long time and that did not affect it, but now it smells so bad it will give you a headache i dont drive it now. Would getting a tune up fix the way it drives the motor wise and i have no idea what the exhaust can be

[oldblu65]

Have your catalytic converter checked !

[MT-2500]

Originally Posted by dssdj2007

Hey guys its been a while since ive been on here with a problem, well let me start of by saying i have a 91 chevy g20 never had any major problems with this van for the exception of a bad ujoint. Just last week out of nowhere it started driving really wierd when i step on the gas it like idle wiered and then eventually will drive ok but when you get to lower speeds it does the same thing on the freeway it drives fine, also it has a really bad exhaust smell inside it just started like that i had the mufller off for a long time and that did not affect it, but now it smells so bad it will give you a headache i dont drive it now. Would getting a tune up fix the way it drives the motor wise and i have no idea what the exhaust can be

Ab good full tune up is a good place to start.

Rick exhaust or engine miss can give you a exhaust smell.

[SS402]

The engine is running rich or the catalytic converter is partially clogged, the converter can be checked easily enough, if tha checks out ok then one or more of the engine controls are not working correctly, most specifically the sensors that have the most impact on the air/fuel ratio; throttle position (TPS), manifold absolute pressure (MAP) or mass airflow sensor (MAF) and the oxygen sensor (O2).Every sensor can be checked for correct operation with common tools, you'll need a high impedance multimeter, vacuum gauge and some knowledge to do your own repairs..