2003 Dodge Grand Caravan 3.3L

I know it's a van and not a sports car. But when I'm on the highway doing about 65mph, I try to accelerate to higher speeds and it's extremely sluggish. Sometimes it's so bad to where the rpm of the engine doesn't move when I press the pedal down a bit to speed up. Low speeds like street driving and taking off when the light turns green there's no problem and takes off fast with a lot of power.

Some said it might be a weak fuel pump, or maybe a dirty fuel filter. I can't check the fuel pressure because my fuel rail doesn't have a service port. New air filter was put in. This problem was going on with the old transmission, and with the new transmission. So I doubt that's the problem (trans was changed because of loss of 4th gear). Fluid levels are fine and clean. The whole exhaust system was changed out, this was also going on before I changed it all out as well.

No Check Engine light.

 

Try stepping it down from 60mph once. 65mph is a weird dead zone between 2nd and 3rd gear on these vans where it won't drop to 2nd, but dropping to 3rd doesn't give enough.

 

Tried it on the highway for a few days and get the same results. It also does it at lower speeds sometimes, but very rare. And when it does, it's nowhere near as bad at higher speeds. The only way I was able to speed it up is to let it take its time and creep to 70mph or press the gas pedal down a lot more, but that causes the engine to go too high of rpms around 4500.

 

Just a guess, but does anybody think that upgrading the trans computer (TCM) will fix the problem with updated software? It's the original that came with the van.

 

Just a guess, but does anybody think that upgrading the trans computer (TCM) will fix the problem with updated software? It's the original that came with the van. This van takes forever to throw a code. It waits for the problem to get worse.

 

The 3.3L in this year makes most of it's power higher in the rpms, like above 4k. If you aren't stepping it down hard enough to get it to downshift, you're not going to have any power.

Upgrading the TCM won't help where the engine makes its power. It also won't make it downshift unless you are stepping it down hard enough to make it downshift.

If you are too afraid to let it run over 4500, you will have sluggish acceleration. Your engine makes it's peak torque at 4000rpms, peak power at 5000rpms, if your not letting it run out, it's going to be a dog.

 

Our old '07 with the 3.8 acted this way, with the addition of a CEL for the cat. The cat was plugged up.

 

More like I try not to take it that far. But since you provided the info of the engine, i'll make the changes. That still doesn't explain why it has gotten worse over time. My van doesn't like to throw codes to bring on the check engine light until it's almost too late. Basically I have to wait for something to break. I thought about brake drag, but why only at high speeds.

 

The exhaust was my first thought, which is why I changed out the entire system (even though it didn't throw any codes). When I did that, I had a lot more power, but highway was still a bit sluggish. I didn't change the O2 sensors though.

 

Hi,

I have similar issue with my Dodge Grand Caravan SXT 3.8L, which is as follows.
-Loose the power suddenly, RPM get stuck at 2000 and car do not pick the speed. It bows between 30 to 40 KM/h. Some time it dose not happen for a week and the issue comes back any time.

-It did few times that engine was quietly shuts down without any knocking while stopped at Red light. I place the gear in parking, start the car and it starts in first attempt. I drive and not issues.

-Few times it had issue where the RPM going between 400 to 1100 back and forth. All dashboards lights start flashing crazy. One time lost the power completely, it won't start. I had portable power booster started the car and never had issue again until this morning while going on Highway on speed of 100 KM/h. Everything start flashing crazy. I was using my Bluetooth OBD-II ELM 327 scanner with my Android phone. I just un-plugged it right away. Took few minutes and everything was normal. Not sure things got better because I pulled out the OBD device or it was on its own got better.

This is happening from last 6 weeks. This is what has been done so far and it did not fix the issue.
-My mechanic said after checking the car that it could be Transmission line oil issue as I have not changed it for a long time. They changed the oil and filter. The issue returns next day.
-After another extensive check he said it is transmission line. So the transmission was changed. Guess what , the problem came back just after few hours I took the car from the workshop.
-I left the car latter for 3 days at workshop and they done the following with no success.

*Translation PCV Volv
*Fuel Pump
*Crank Sensor
After my workshop team exhausted doing everything and not able to resolve the issue, they asked me to get the scanning report from the dealer and then they will see what they can do for me. I already spend 1300 Canadian Dollars so far. Going to dealer has another challenge. The car start working OK for a week. When I went on my given appointment, they said if there is no issue for the time being they won't be able to trace anything. So they asked me to come back when the issue start again. The problem is the issue may come for 5 minutes and the for another week there is no issue.

I decided to track the issue myself by monitoring through the OBD-II ELM 327 and "Torque Pro" Android software. I bought the app and now in the middle of setting up. It has its own challenges. Not all the PID cods are there for Dodge Grand Caravan 2006. There are quite a number of sensors that I can monitor. I talked to dealer technician and he gave me the name of the sensors that I can start with. Not sure all of them are there or not. I tried to search all over the Internet and seems no where I find those PIDs. Has anyone know where I can find them. I am also using an add on app with "Torque Pro", called "Torque Scan" that sends all the Hexadecimal codes to car computer to listen if it returns an reply. That is a quite time consuming as it has to go each code and to find out which one this particular car has. I have already spend running the car for 2.5 hours and yet not completed the list even half of it. I will start the scanning next week on Saturday early. But if some has any information what is wrong with my car and where can I find the PIDs for this model.

Thanks.
SA