need help!! 2.9 hesitation

[jamesb-862.9]

first off i have a 86 2.9 v6 it was my dads and he gave it to me 2 years ago ...so recently i started noticing the engine hesitating a lil when i stomp on the gas peddle like to get on a freeway or what ever..... so i take it to a shop and he tells me its my injectors so i buy them $650 dollars later i still got the same problem but now its gotten to the point that it does it under normal drivingvery bad and jerks me around and after it warms up for maybe 20 min it wants to shut off... i changed every sensor you could think of and also the gasket on the upper intake manifold and also removed the cats thinking they where clogged... also when i put my hand over the throttle bodie it doesn't choke it continues to run.. ive changed the egr valve, o2 sensors, fuel pumps,knock sensor, air control valve, throttle position sensor, and and map sensor... i dont know what else to do any advise would help

 

[IMenriched]

first off i have a 86 2.9 v6 it was my dads and he gave it to me 2 years ago ...so recently i started noticing the engine hesitating a lil when i stomp on the gas peddle like to get on a freeway or what ever..... so i take it to a shop and he tells me its my injectors so i buy them $650 dollars later i still got the same problem but now its gotten to the point that it does it under normal drivingvery bad and jerks me around and after it warms up for maybe 20 min it wants to shut off... i changed every sensor you could think of and also the gasket on the upper intake manifold and also removed the cats thinking they where clogged... also when i put my hand over the throttle bodie it doesn't choke it continues to run.. ive changed the egr valve, o2 sensors, fuel pumps,knock sensor, air control valve, throttle position sensor, and and map sensor... i dont know what else to do any advise would help

Look over the vacuum lines carefuly...might be a vacuum leak some where.
could be a bad connection and or ground.

the only thing you haven't changed, not listed anyway, is the FPR (fuel pressure regulater)...did they scan for codes?? what was present??

might be the pick up coil inside the distributor ...also the TFI (ignition module)
needs to be checked.

other than that it appears youv'e covered just about everything else

 

[jamesb-862.9]

well ive changed all of the hoses that looked bad or had cracks... and i forgot to mention that when i installed the injectors i also replaced the tfi ignition modual...the codes it gave me were..,,,,
KOEO code-89......mem code 33 egr valve no flow..mem code 11........


KOER.......CODE 41 Ho2 SENSOR SYSTEM LEAN BANK 1........CODE 25 DYN RESPONSE TEST KNOCK SENSOR NOT DETECTED... as i posted b4 i replaced the knock sensor and egr valve as well as the o2 sensor i have no idea what some of the codes mean so i couldn't fix or replace what needed to be fixed....

 

[IMenriched]

well ive changed all of the hoses that looked bad or had cracks... and i forgot to mention that when i installed the injectors i also replaced the tfi ignition modual...the codes it gave me were..,,,,
KOEO code-89......mem code 33 egr valve no flow..mem code 11........


KOER.......CODE 41 Ho2 SENSOR SYSTEM LEAN BANK 1........CODE 25 DYN RESPONSE TEST KNOCK SENSOR NOT DETECTED... as i posted b4 i replaced the knock sensor and egr valve as well as the o2 sensor i have no idea what some of the codes mean so i couldn't fix or replace what needed to be fixed....

check the tech Library...there is a section on the codes

 

[dirtybird62]

first off i have a 86 2.9 v6 it was my dads and he gave it to me 2 years ago ...so recently i started noticing the engine hesitating a lil when i stomp on the gas peddle like to get on a freeway or what ever..... so i take it to a shop and he tells me its my injectors so i buy them $650 dollars later i still got the same problem but now its gotten to the point that it does it under normal drivingvery bad and jerks me around and after it warms up for maybe 20 min it wants to shut off... i changed every sensor you could think of and also the gasket on the upper intake manifold and also removed the cats thinking they where clogged... also when i put my hand over the throttle bodie it doesn't choke it continues to run.. ive changed the egr valve, o2 sensors, fuel pumps,knock sensor, air control valve, throttle position sensor, and and map sensor... i dont know what else to do any advise would help

I know on the old school carbs, when you smothered it and it still ran, you had a vacuum leak somewhere. I'm in the same boat as you with my 87. I even swapped out the computer to no avail. This week I'm going down the line with new plugs, checking compression and coil spark.

 

[jamesb-862.9]

it ended up being the oil breather was missing the rubber seal so when i coverd the throttle bodie it was sucking the air threw the oil breather so i clogged it up and took it for a trip it ran just fine no hesitation....

 

[90B24wd]

This is a very good thread. Sloving hesitation problems can be very fustrating on 2.9's and 4.0's. I think that this should be saved and posted.