1994, 3.8, No Power

[magoogle]

Hello all, I am at my wits end on this van. it runs great, has no check engine lights on, shifts well.

I have noticed that the power on this van is cut down to a third power when it is put into drive, and or going down the road. Seems to have full power in reverse.

The exhaust has been checked.
Air intake is good, as long as it is not in drive
TPS was replaced
New Fuel Filter
Fuel Pressure checked
Coil packs and base replaced

Manually shifting does not help the power, it is so weak in drive. you could press the accelerator to the floor from a dead stop in gravel, and it would not even spin the tire. Going down the road, it eventually gets up tp speed. I would appreciate any input.

[LMP]

Only problem I had that had some similarity was a dirty Mass Air FLow sensor. It is located near the TPS, and the sensor itself is a thin piece of metal wire in the middle of the incoming air stream to the intake manifold. In my case, it would accelerate quite normally, though slowly but if I wanted to accelerate to overtake, it would not respond at all...but after 4 of 5 seconds, it would dare to gain some speed.
Fact is I had run the car without an air filter for some time and air carried mud particled had accumulated on the wire, causing insulation against air flow cooling. (wire electrical resistance changes with temperature). CLeaned it with alcohol and q-tip or small paintbrush........and reinstalled an air filter.
I have exerienced nothing other than that..so that were my 2 cents.

[bill2min]

[quote=LMP] i have the same as you did lmp but i have the 3.1 it takes of fine but if u step on it when ur up speed and want to pass on on the highway it takes 4 to 5 seconds to pick up some speed

[magoogle]

I forgot to mention that I tried a known good Mass Air Flow to no addue.

[LMP]

[quote=bill2min]

Originally Posted by LMP

i have the same as you did lmp but i have the 3.1 it takes of fine but if u step on it when ur up speed and want to pass on on the highway it takes 4 to 5 seconds to pick up some speed

THe 3.1 (at least in '93) does not have a MAF sensor: it has a MAP sensor (manifold air pressure) but the intent of the MAP is same as MAF, although the computer code for using that information is different.

[llerrad]

How did they check the exhaust? did they remove it above the converter? sometimes a converter will break apart inside and block the exhaust, on the outside looks and sounds like it is all working well but when you need power it will block the flow of exhaust and no power very sneeky this problem have had it happen twice.

[LMP]

Totally agree with Illerad....did happen to me..long time ago, there were even no catalytic in those years. THe exhaust pipe (was a 1968 FOrd Galaxy500 ) was like done of 2 layers of sheet metal and the inner sheet bulged inside the pipe, blocking the exhaust. Of course, for the outside, there was nothing to see and it took a long time to finally understand what was going on......

[giantxtcpro]

Illerad is right but u may also want to check sparkplug wires