91 econoline 4.9 six white smoke/ fuel /sputter

[mrbridgeport]

Hello,

I have a 1991 4.9 liter six cyl econoline conversion van which is now sputtering white smoke, and seems to be getting way too much fuel. You can smell fuel on carbon monoxide like crazy. If you hemmer the gas peadl down it will at times billow white smoke.

The O2 sensor and map sensors are fairly new. They were replaced within the last 6 months. In fact this is my second o2 sensor. I also checked the vacuum hose that goes to the map sensor and there is no restriction. It seems to idle fine when started (first started) and as long as the gas pedal is lightly touched and not stepped om too hard, the van seems to run fairly smooth up to a certain point. Then after a few minutes the it will start to idle very rough and blow white smoke. It seems to run fairly smooth as long as you don't take it over 25mph too.

It wil then just seem to be fine and run smooth, then it can just start to sputter, run very rough, loose it's idle while parked and shake and chug until you hammer the gass and get the van to bounce to overdrive, then it seems like it snaps out of it and kinda goes away.

Since the new map and o2 were changed, the engine light still comes on from time to time. I had that cleared and the computer reset (as well as the timing reset) a few months back. I was told that there is either a short in the o2 sensor wire or the computer is funky and needs to be replaced. I have been told that twice.

I was also told that it may be a shot catalytic converter fouling this stuff up? restricting air flow etc.

Any help would really be appreciated. This van has a brand new head on it, new brakes, new waterpump, radiator, plgs wires, rotor, distributor, shocks etc. ...so I don't want to give up on her and I can't afford to buy something new.

So is it the computer?
Is it the MAp and or O2 Sensor?
Or is it a restricted Catalytic converter?

Please clue me in, I really can not afford to just throw money at this problem.

Joe Ryan

Joe Ryan

[EricJohn]

I had a '90 E 350 with the 460 and it would plug up catalytic converters every 40k,.

_- it just wouldn't run -_ like someone would just shut the engine off, never to start -or- run.
the second time on a freeway, I drilled a few 1/2 inch holes in front of the converter to let off enough pressure so it would run to get me off the roadway -and- into the shop.

my '89 now has a very similar system - hopefully I don't have the same problems.

[BroncoJoe19]

I have a 1991 4.9 liter six cyl econoline conversion van which is now sputtering white smoke,

white smoke is steam, you may have a blown head gasket.

[disableddude]

if he has had a new head fitted then he needs to have a full inspection on the rest ie bores and all waterways check oil as well cos that may turn white if water is present. white smoke is definatly water.