1996 Dodge Caravan Bogs When Accelerating

Hi,
I have a 3.0 '96 Dodge Caravan that bogs when you press the accelerater to fast. If you gently accelerate, the car runs great. If you are at idle or driving and suddenly accelerate hard or too fast the car bogs as if it was getting too much air and no gasoline. The car never dies from lack of gas. Below are the steps we've taken with no success of fixing the problem.

1.) We have checked for codes and received a P0121 so we replaced the Throtle Position Sensor which caused the code to go away.
2.) Replaced the Fuel Filter
3.) Replaced the Fuel Pump
4.) Replaced the Air Filter
5.) Checked for any air leaks in the engine
6.) Checked for any electrical leaks in the plug wires.

What else can I check to hopefully correct this problem? Your help will be greatly appreciated.

When you changed the fuel pump I assume you replaced the complete unit including pickup filter and fuel pressure regulator.

How many miles on vehicle and have you chnaged the timing belt. Check the timing.

Get a can of carb. cleaner and spray around the intake manifold if you find a big vacuum leak it will smooth out. Pull the hose to the vacuum booster and put a bolt in it can you gun the engine with this plugged. Bad vacuum leaks cause big problems.

When you changed the fuel pump I assume you replaced the complete unit including pickup filter and fuel pressure regulator.

How many miles on vehicle and have you chnaged the timing belt. Check the timing.

Thanks for the reply tempfixit. Yes, the new fuel pump had a new pressure regulator and pickup fiter.

Get a can of carb. cleaner and spray around the intake manifold if you find a big vacuum leak it will smooth out. Pull the hose to the vacuum booster and put a bolt in it can you gun the engine with this plugged. Bad vacuum leaks cause big problems.

Hi, tried the old carburater cleaner trick to find an air leak but had no luck.

Use a Haynes manual and ohm the coil to determine it is satisfactory. Use a good logic probe and look at the pulse from the camshaft position sensor in the distributor. Also check for pulse on the crankshaft position sensor. My Waekon has an amber light for a pulsed signal. I have ohmed the wires for these two sensors in other vehicles.
If you check enough you can just about pick this up in a test drive.
Ask the parts store if they will let you monitor the oxygen sensors,T-P, temperature,map sensor,ect. This will be a big help a good scanner will do this.
Also check for loose grounds.
http://www.ntxtools.com/ They have a reasonable price for a good logic probe.
Look on ebay for a nemisys code scanner or a 3140 equisy's scanner with freeze frame and 25 functions which be monitored. I paid $210 for my scanner.

rhandwor - Are you our new moderator or are you just popping in?

Just dropping in as far as I know.

Use a Haynes manual and ohm the coil to determine it is satisfactory. Use a good logic probe and look at the pulse from the camshaft position sensor in the distributor. Also check for pulse on the crankshaft position sensor. My Waekon has an amber light for a pulsed signal. I have ohmed the wires for these two sensors in other vehicles.
If you check enough you can just about pick this up in a test drive.
Ask the parts store if they will let you monitor the oxygen sensors,T-P, temperature,map sensor,ect. This will be a big help a good scanner will do this.
Also check for loose grounds.
http://www.ntxtools.com/ They have a reasonable price for a good logic probe.
Look on ebay for a nemisys code scanner or a 3140 equisy's scanner with freeze frame and 25 functions which be monitored. I paid $210 for my scanner.

Thanks rhandwor. I will give these suggestions a shot this week and keep you posted.

Sergio did you pin point the problem yet? I seem to be having the same problem with the same excat van you have. However mine decides it's going to shut down while I'm driving it then won't start for a couple of second's then fires right back up. I just had a tune up with all new plugs, dist cap, rotor & replaced the TPS as well.

Check the wires by looking at them at night.

If you see any stray electrical sparking, you know that the wires are the theives!

Jim

Hi guys,
Sorry for the late reply, I ran out of Cash so I had to let the van sit up until last week. I have not yet solved the problem. I replaced the Oxygen sensor which made the van run a little better but it did not cure the problem. In fact, I took it out on a test drive and it quit on me all together. I had to have a friend help me push back into the driveway.

So now I have a new problem, the van quit and will not start. Lights come on, door locks work, horn works, etc. but it will not crank over. I'm going to check the starter and battery tonight.

I think this van may be headed to the crusher because I'm really starting to hate it!

you're driving a dodge. maybe u didn't hear me - i said a DODGE. it wasn't meant to last this long.

you're driving a dodge. maybe u didn't hear me - i said a DODGE. it wasn't meant to last this long.

I currently have two, 96 & 98 caravans, each with over 160k, one with the original tranny. My 96 neon with 180k was just put out to pasture as it has unsolved brake issues, but I may bring it back if I have the time to work on it. If you're carefull with frequent oil and trans fluid changes, these cars can run a long time.

That being said, my 96 also likes to think a bit before moving under rapid acceleration. I'll check what's been said so far.

Update on dead Caravan.

The van will not start with the key at all. All instrument lights come, radio, door locks, etc.

Tested the starter by using a by-pass switch connected from the battery to the starter relay and the key in the ON position. Car started fine.

Tested the relay with a multimeter, tested fine. Replaced the relay with a spare but the van still will not start with the key.

Was going to test the Neutral Postion sensor but since the van started while testing the starter in the neutral position it kinda of rules out that sensor being bad.

Started to disassemble the ignition swith last night but ran into a snag with one of the screws. Looks like I need to find a tamper resistant star screwdriver, T15, to remove it.

I'll post the results of the switch test tonight.

You may be missing the ground path to the starter relay coil. The PCM provides the ground. What makes the PCM turn on this ground? I posted this same question a while back and got these responses:
http://www.automotiveforums.com/vbulletin/showthread.php?t=923480

You may be missing the ground path to the starter relay coil. The PCM provides the ground. What makes the PCM turn on this ground? I posted this same question a while back and got these responses:
http://www.automotiveforums.com/vbulletin/showthread.php?t=923480

Thanks, but I also hard wired a ground to slot 85 of the starter relay but it still did not work.

I also read someone having the exact same problem and that in their case it was the ignition switch. I replaced the ignition and still, no go.

Do basic cks with a test light with the starter relay removed. Clamp end on battery neg post ck pin 30 should be hot at all times. Pin 86 hot with ign in start position. Light clamp to pos post and pin 85 should light with trans in park and neutral. Light should be bright; ck at battery to compare the brightness of the light. Remove the air cleaner and inspect the 2 connectors under the battery. Acid drips on them and cause alot of problems. When you get the van running I would ck for a restricted exhaust (cat).