95 gmc sonoma vortec

[joe bellomy]

95 gmc sonoma stalling in reverse.

hi everyone and thanks for all the good info here.


I have a 95 gmc sonoma with a 4.3l vortec engine with issues. First off it stalls at idle in park but idles fine when in gear. sometimes it stalls when coming to a stop. It always completely stalls in reverse. it stalls when i climb out of the drivers seat but idles fine when i'm in it. stalls and lopes till it's warmed up then gets better. codes say egr and map. i've already replaced the egr with no change. had the map sensor tested off the vehicle and it was good but when i test it on the vehicle the voltage jumps all over while i'm increasing the rpm. it will not shift into 3rd or 4th gear though I believe those gears are burned up as the fluid was shot when i got it. abs light is stuck on. It's a beautiful truck and i'd like to get in good running order. I think I need to resolve the engine issue before investing in a new tranny as it seems this may also be causing the shifting problems. any help would be appreciated.

thanks. jb

 

[threecar]

There are lots of similar threads on this forum. You should try doing a search. Not sure how you can fix the engine without 3rd and 4th gear though. Try cleaning the IAC valve and I think it is the throttle position sensor? Both are on the air intake. Also seafoam the engine.

 

[joe bellomy]

thanks for the reply. i did review all relate threads. the tps checked good as did the iac. just odd that the map tested good off the engine and bad on. i going to redo that. i'm thinking some kind of vacum problem? as i'm still getting and egr fault though that has been replaced. waiting of a vacuum gauge. i did seaform the engine to no avail. do you know if the sensor in the bottom of the air intake boot needs to be facing a particular direction?

 

[threecar]

I don't think it needs to be facing a certain direction. I have taken mine off countless times and never looked as to how I was putting it back in. Sometimes egr does get clogged rather quickly. How about plugs, wires, dist.cap, and rotor?