I still have the third cat and have not pulled injectors to clean them, I have ran injector cleaner in the gas which didn't make any difference. Don't think injectors are the problem being it runs so well with the VAF disconnected. When I cleaned the VAF , I didn't spray up inside the sensing ports for fear of leaving a film on the optics. Still runs crappy, some days worse than others.

 

I feel your pain....your injectors are probably fine... how about fuel filter?

When i cleaned my VAF, i removed the sensor from the housing itself... by removing the 3 phillips screws. I doused the whole thing in cleaner and wiped it with a paper towl. Dried it with a hair dryer. Be careful when you re-install everything cos if you don't put it in straight you run the risk of cracking the lower plastic... I ended up cracking mine and sucking a little plastic sliver into the engine! My car started to fall flat on it's face when i'd accelerate. After 5-10 mins and a few WOT runs it went away... THANK GOD!... but don't be an idiot like me and do it when you're in a hurry. I guess it melted outta there.

My car has been running a lot better ever since. Also i've noticed that the car runs poorly when it's low on gas and seems to stay consistantly running better when i don't let it drop past 1/4 tank.


Also motor/ tranny mounts could be a problem. when mine were bad i felt a hesistation. Also theres a rubber bushing that attaches to the rear differential, and if it flexes could cause a slight hesitation.

If yours is anything like mine was, it's a studder when taking off only under slight acceleration. Almost like the tranny is inbetween gears. A torque converter and fluid change could fix that. I think i remember you saying that you'd already done the tranny fluid change however...

 

I tryed changing the fuel filter but couldn't get it out, the flares are expanded inside the filter housing. But it runs fine when it's cold or with sensor disconnected. Don't think mounts are a problem for the same reason. Trans might be a problem. It's only when the car gets up to normal operating temp when the hesitation happens.

 

Fuel pump is submerged/cooled in the gas tank above 1/4 tank, that's why it's better for the life of the pump to not let the tank go below that point.

 

Oh thats why it runs better with 1/4 tank. cool...

Rbert where are you in California? I'm up in the top of the state at humboldt state University...

Weird that your hesitation starts when the car is warm...Mine only happened when the car was cold..

 

It shouldn't run any different. The fuel acts as a lubricant for the pump, I used to run my truck on empty all the time and had to replace pumps a couple times. Im in San Mateo, nice where you are up there, Eureka's a cool town.