I got a call back from the trans shop and gave me the news that the transmission was not the cause of my 2-1 downshifting problem. I had it towed in since I was not comfortable that it would make it all the way to the shop. They test drove it and thought it was the valve body and took it apart to check it. Not the problem. After another test drive, determined that it was lack of engine power causing the transmission to not downshift properly. Rebuilt motor and rebuilt tranny so what could be left? This problem has plagued me since I bought the beast. No low end power and no 2-1 downshift.

What's left? Something is not sending a signal or receiving a signal (PCM). Man, you just want to start off with a clean slate sometimes and buy them all new to get by another 10-15 years. I gotta find my old voltmeter or get another and start checking voltage. Trying to narrow down where to start and here's what I have.

1. Figure it can't be coil or distributer since it's either working or not. The idle is fine, it starts no problem, and the timing is right.

2. Since it is a 91, it doesn't have a crank or cam position sensor. It also did not come with a throttle body temp sensor on V6. There is no IAT sensor or IAC sensor either for this year.

3. The coolant temp sensor, oil pressure sensor, and idle speed control are new.

4. That pretty much leaves the Map sensor, Throttle position sensor, Oxygen sensor and GOD forbid PCM.

Any ideas? Anything overlooked?

 

hey sixgun, did you rebuild the engine,or did someone else do it?? reason why i ask is how was thw timing chain put on was it mark to mark straight up,or was it 2or 4 deg. advanced or retarted ?? i know this will effect the power out put of the enging. good luck

 

Have you checked the throttle rod adjustment and make sure no springs or parts are missing from the linkage?

 

I adjusted the throttle rod and it helped the 3-2 automatic kickdown but did not affect the 2-1. Before the throttle rod adjustment, it did not manually downshift while driving. It appears complete as compared to the manual.

As far as the timing chain. I had the motor sent out for rebuild and if memory serves me, it was lined up. But this problem was before the rebuild and after. I really think it's something that was originally messed up from when I bought it. It just picks up real gradual to about 20 mph.

I haven't gotten the truck back yet. I just talked on the phone to them yesterday morning and had to go to work in the afternoon. I'm off tomorrow and debating taking a chance driving it to my inlaws which is half way home but worried about no inspection sticker. If I tow it again ($$$) do I take it home or a shop or dealership. If I take it home and still can't find the problem, that means one more tow ($$$). Heck, I probably could have sprung for a DRBII tester instead. I'm on vacation this next week and really want to resolve this but if I give up another vacation for this truck, my wife will chop my nads off.

 

hey sixgun,i here what you are saying.could be a long shot,but did you ever think about the computer,it controls just about if not everything.
i broke down and took mine to the dealer{mission cjd} which i never did,but who knows these trucks better or have the equip. to work on everything dodge than the dealer.may say you a bunch of headaches.
good luck with what ever choice you make,keep us posted. thank you

 

Since you believe it is a lack of engine power have you checked the injectors? Are you running oversized tires? Are you sure it is the original rear gear ratio in the truck?

 

Seems like a whole different ballgame now. I went to the trans shop and test drove it with the mechanic. Kickdown works now. Problem is that the motor sounded terrible. He didn't mess with anything, motor-wise. When he first fired it up, it was missing real bad in park while revving it up. On the test drive it was floored and wouldn't go above 30 mph. When the truck stalled out on the last drive before getting it towed, it did this and stalled out. It was flooded out. Let it sit and it drove away. Could flooded it out have messed with something else?

Fresh tank of gas, new fuel pump, seafoam in tank, new fuel filter, new rubber fuel lines, professionally cleaned fuel injectors. It really sounded like the timing was off but I had set it previously. I've revved it plenty and it sounded great in park before.

Well decision time came and I had it towed to a shop by the house that does a lot of fleet work. $39.95 to diagnose it and nothing if they do the repair. I really want to get this animal on the road!

As far as the computer, yeah I've thought about that a lot but didn't want to go that route without checking the last 3 sensors first. Tires are standard P235-75R-15's and the rearend doesn't look like it has been touched in 20 years. Times like this, I wish I had waited for a 78-79 like I originally wanted. I know that once it's running this will just be a glitch in my memory though and it will all be worthwhile. I'm only in about $3500 so that's not too bad.

 

It is really hard to diagnose a problem when every time you post the problem and symptoms are different. LOL

Good luck with the shop.

 

may be it could be your valve timing is off,and your initial timing is showing it is wright. i have seen this happen before with older non magnum engines. timing chain could have been put on dot to dot straight up and down,but was the correct piston up to top dead center. that is why i asked about the timing chain.
you did say it was like this before the rebuild,running this way,so maybe that not could be the problem either, just some info for you.
seems like you just dont have enough spark,since you said it flooded,its tbi injection,should not flood unless there is no spark to burn the fuel the computer is sending,to the injectors via gas pedal.. any check engine codes??? good luck

 

aje1227; Injection systems are different from carbs in many ways including symptoms. A TBI system that is not atomizing the fuel properly, and is pissing streams instead, can exhibit flooding problems while also showing loss of power symptoms because the fuel is in a non useable state.