91 Dodge Caravan Engine sometimes runs a little rough & will not get any power

[dnr79065]

Hello!

I have a 1991 Dodge Caravan ES 3.3L engine with 222.060 miles on it. The engine will sometimes run a little rough and will not get power. This has been an off and on thing for about a month now. It is March of 2007 and this week the van ran good on the 12th,13th and the 15th (cooler days mid 60's) but the 14th was in the 70s, I took the van and drove it 5 blocks and filled the gas tank, then I drove it about 5 miles more to my husbands work, shut it off waited for him about 5 minutes. restarted van (Speed Limit in parking lot is 10 mph just so ya know this is not highway speed) got to the security gate and the motor started running a little rough and WOULD NOT GET ANY ACCELERATION, So I pulled over to the side put it in park, Motor ran just rough enough to give a slight shake to van NOT TO MUCH, But you knew it was there. It would accelerate fine in park but when it idled back down it was still shaky. waited about maybe1-2 minutes the problem went away and van ran fine... No check engine light came on, van did not die but did act like it was going to. have not changed out the Fuel pump yet ($173.00 ) it is on my list though. Have heard something about Upstream O2 sensor ($41.99 BOSCH) Not sure but does anyone know if this could cause this also? Almost forgot to add this van has doubled in gas usage since this happened. We would use 1 full tank from payday to payday (by weekly payday's). Now it takes two tanks. 120 miles a week is what the van is driven.

[jsinton]

These symptoms are like a problem I had once with the Exhaust Gas Recirculation system, or EGR system. The EGR system is located on the intake manifold or in a pipe connected to it (I don't have a 91 3.3L). On the 3.3L and electric EGR transducer serves works from a electric solenoid, so in other words, you'll have a electrical connector going to it. What happens is this thing goes up and down as you press on the gas. What it does is allow some suction toward the gas tank to suck off the gas vapors that would otherwise go into the atmosphere, and leans out the mixture to increase your MPG. Sometime when the van is old, these get gunked up and do not move up and down correctly, getting stuck in the "up" position, and allowing too much vacuum into the intake, or in this case gets stuck in the "down" position, not allowing enough air in the mix, causing too much fuel to get burnt and loss of power, along with poor acceleration and MPG. The 5 cent fix is to locate the thing and clean it out (somehow).

The book says you can see the stem going up and down as you apply the gas. If the thing doesn't move up and down, you know you have a problem.

Other possiblilities are:
Bad distributor
Incorrect timing (not likely)
Bad fuel pump
Clogged fuel filter
Needs tune up
Defective Coil
Binding brakes
Transaxle slipping

Good luck, tell us how you make out.

[jsinton]

For more info in the EGR system, see here:

http://www.autozone.com/servlet/UiBr...3d801a41dd.jsp

[RIP]

Yes, an O2 sensor could cause this though your symptoms seam a little extreme for it. Usually they create stumbling and hesitation. Usually they generate a CE light. I said usually.

Simple stuff first before you spend some bigger bucks. Have you tried fuel conditioner to get rid of any possible water condensation in the fuel tank? Are the plugs, plug wires, and distributer cap/rotor (you might have them) in good condition and connections clean? You could try cleaning the throttle plate and idle air control valve in the throttle body. SeaFoam cleaner seems to do a good job. The EGR system is another possibility.

Usually (again) when a fuel pump dies it is consistant. A good indication of a bad pump is lack of acceleration/stumpling up a hill (under a load), lack of high speed performance, or the van won't start. Your's could be on it's way to that.

Here's a good source for info. Beyond that, I would buy a haynes or Chiltons manual especially if like most of us, you want to do all you can to avoid the dreaded...dealership or shop. http://www.autozone.com/servlet/UiBr...ginRepairGuide

[Bernard Feltzer]

A van with that many miles could have many causes for that problem.
There is no distributor cap on that engine. I am pretty sure that model year with that engine did not use EGR. It does have the canister purge valve.

Using twice as much gas all of a sudden?

I would check the cat converter for blockage, all the rubber vacuum hoses for any leaks. The MAP sensor, crank sensor with a scope.
The O2 sensor can be checked with a scope.
Any increase in oil consumption?

[dnr79065]

Thanks for all the Great Advice and for the http://www.autozone.com/servlet/UiBr...ginRepairGuide (I didn't know that site I was there) and it was so helpful, I did add a conditioner to the the fuel tank Friday. Sat it was in upper 70's I drove the van all over town just trying to get to do it again but it wouldn't. Today it is going to be 85 and I am going to try again today. I did talk to Auto zone they said that in the last 3 months there had been allot of complaints about excessive water in the gas here. and they sold me two cans of B-12 Chem tool. I was hesitant to try because I have heard several horror stories about additives causing more problems rather than doing any good, But I did it any way they told me to add both cans, But the can stated 1 can for every 15-20 gallons of gas and my tank is 15 gallon so I only added the one. Maybe Just maybe that was the problem I HOPE, If not I will be following all the other avenues offered to me by you all.

[RIP]

Always, always, always follow the directions from the manufacturer. Smart move. Hopefully you've lucked out with an easy fix. You might want to consider changing the fuel filter too.

[dnr79065]

Hey everybody today is the 19th and to my surprise the van is running fine so far. no repeats yet. I will run this tank down some then install the new fuel filter this Sat and see what that does. it seems a little sluggish or slow up hills so we might go ahead and purchase the new fuel pump for it also. but other wise doing good. I will log on here and add what the final fix is or if I need more advice.

[RIP]

Great news. Hang in there. Keep on keeping track of your mileage and see where it goes.

[dnr79065]

Ok it is Thursday the 22nd today's agenda was took Hubby to work and it rained all day temps where in the 60's and cloudy. Pick up hubby at 4:30pm made it back into town made two stops shutting the van off at both stops started home from the second stop and it did it again everything was the same pulled over raised the idle until it started running smoother? I did notice that most the time it does this the van is at or below a quarter tank except for that day I filled up the tank and it did it then, I thought for sure we had it pegged.

[vipergg]

Are you getting any error code thru the MIL ? Could be a problem with something like a TPS worn spot .
go here for info.
http://www.allpar.com/fix/80s-codes.html

[dnr79065]

Originally Posted by vipergg

Are you getting any error code thru the MIL ? Could be a problem with something like a TPS worn spot .
go here for info.
http://www.allpar.com/fix/80s-codes.html

No CE light at all.

[Bernard Feltzer]

Since it acted up when it gets wet or humid, I would check spark plug wires where they plug into the coil pack. Look for green corrosion inside the terminals or near the rubber boots.

You have a camera, take some closeup photos of the engine and post them, maybe one of these old geezers will see an obvious problem.

[dnr79065]

I was reading 95 Dodge Caravan 3.8l V6 fuel problem.

OK now I have a question????

Here it goes,

On my 1991 3.3L caravan ES do I have a little screen in my fuel tank?
I have looked in the HAYNES repair book but I have found no mention of one.


And COULD that cause my problems which now seem to only occur now twice a tank.

1. I fill up (it will do it ONCE after i fill the tank. I will get about 3-5 miles from gas station and it will act up. I will pull over stop put it in park, let it sit for about a minute or two and it starts running fine.)

Then I can Drive Drive Drive with NO problems.
And it won't do it again,

UNTIL...

2. My tank is 1/4 or below (every time the tank drops to that fuel range it act's up.)

Then I go fill the tank and start all over.

I did purchase this van used, and it did sit for 1 yr before I purchased it with no pump in it, just an open hole.
I did have a fuel pump installed but I am pretty sure that the tank was NOT cleaned.
If you know the screen is listed in this book could you please give me the page number that it is on.

[CowboyMiller]

hehe....i am so dredding dropping my tank AGAIN..just to clean out the in-tank filter..lol...i wonder if i could get away with not doing this if I fill my tank up like you do..haha..though that woudl suck to drain out a full tank then as oposed to a 1/4 tank now...I love my van...