Ok to start with im really leaning towards the ECU being bad but heres the problem I reset the computer the other day to clear the codes and while doing so i pulled the EFI fuse. after doing this when my tranny 'Automatic' goes to shift into 2nd the engine dies but I can slam it down into low and the engine will catch again. After a while it will finally shift into 2nd but will hesitate and usually gets better as it warms up. Also when i go to stop, when the speedo hits 15 the engine will die , most of the time sometimes it catches and don't die sometimes it wont do it at all and run normal. Im pretty mechanically inclined but as to the situation im highly confused if anyone has any ideas just post them please.

Already tried, replaced AFM, tested TPS, tested O2 sensor-i think may be bad
reset computer several times any ideas i need major help!!!

 

does it idle fine when its in park?? and it only acts up when you driving? did you get any codes? my first thought is to flush the tranny and change the filter. but just my first guess

 

yea man it idles pretty good i mean not perfect a lil rough but typical 3vze but when goes to shift its like either the fuel or the spark gets cut completely cut of and no.. no codes.. except knock sensor which ive always had and i dont see causing this...

 

the knock sensor will cause a lot of problems and is a PITA to change. read up... lots of threads on here about it. open your wallet and time to get your hands greasy.

 

ive had the truck for about four months with the check engine light on for the knock sensor and it started this about 3 days ago after i removed the cable its just hard for me to see it causing problems now.... not shooting down any ideas

 

i must have missed it but what cable are you talking about? the knock sensor may not be the only cause of your troubles but it certainly doesnt help. but i keep thinking its the Knock sensor and a tranny flush well help. but ive been known to be wrong a time or 2...just ask my wife..lol

 

lol no kidden and i removed the negative cable to reset the computer and it started doing this thats why im leading towards the ecu... unfortunately

 

I doubt its the ECU if it idles and revs ok by your description,, Maybe trans wiring harness short. track that harness and look for spots that may be rubbing.
Also recheck the connection to the AFM.
If you put and Ohm meter to the O2 sensor then it is bad now.

As for the knocksensor problem.
Try advancing the timing just a little bit and pull the small vacuum hose loose from the EGR main valve, When in limpmode the ECU retards timing drastically and richens the fuel bigtime and in an auto its just hell. (stupidest crap Denso did)

 

yea man i have the timing advanced pretty far but its set by feel and how much power it has but i just purchased a new computer that should be here by friday and if that dont fix it then off to the shop because i havent found any shorts in the harness and me and my dad have ohm'd out all the sensors and they've all tested good repaced VAF and TPS replacing TPS helped a small amount now it doesnt die when you go to stop but still does not like to shift into 2nd but once it shifts it usually will skip and miss in other gears and once it gets it out its system it runs fine maybe cutting off here and there i feel like the computer has to relearn the truck every time.

Punchy-ive never heard of pulling the vaccum hose off the EGR valva What does this do?
thanks for the input

 

Whats up!im a newbie to four wheel drives.I was wondering what is a good website to buy stock and aftermarket part for my 81