00' Voyager - Dies when you shift into Drive

[thetandycollector]

Hiya all,

I have a 1998 Grand Voyager SE w/2000 model eng/trans/computer. This van was a running and driving van in a local medical transport fleet for many years, and was purchased about two years ago by one of the fleet drivers for his own personal vehicle. I've been servicing it ever since.

Recently, he's had issues with hard-starting, and then eventually, it just wouldn't start at all. Had it towed in and pulled the codes to find P1391 resident in the computer (CMP/CKP sensor intermittent signal). Both sensors where replaced, engine started, and code was resolved. However, car now dies when attempting to shift into drive, has poor idle quality, and after trying to shift into drive more than twice, it will simply not start back up until the CKP sensor has been disconnected and then reconnected.

I would also like to add that we have replaced the ignition coil pack. No other codes are present. SES/MIL light comes on and off at random.

We have toyed with adjusting the distance of the CKP sensor from the tone ring. Any of the adjustment distances where the car will still run, it still will not run in drive, with the exception of when the tone ring is ACTUALLY PHYSICALLY CONTACTING the sensor. That only worked one time.

Any suggestions?

Bill S.

[jpb53]

Possible broken flex plate.

[GNXdreamin]

i had a similar problem in my '96 T&C. Turns out the flywheel was broken, which was throwing off the crankshaft position sensor. Since the flywheel was broken, the reference marks on the flywheel were off, and was causing the crank angle signal to drop out. Damage ate through the flywheel, parts of the flywheel to crankshaft bolts, and also into the rear main seal housing and seal. Replaced all of that, and now it's doing fine. Good luck!

[thetandycollector]

Originally Posted by GNXdreamin

i had a similar problem in my '96 T&C. Turns out the flywheel was broken, which was throwing off the crankshaft position sensor. Since the flywheel was broken, the reference marks on the flywheel were off, and was causing the crank angle signal to drop out. Damage ate through the flywheel, parts of the flywheel to crankshaft bolts, and also into the rear main seal housing and seal. Replaced all of that, and now it's doing fine. Good luck!

Thanks for the advice guys, I kinda figured that was the problem, but since the shop was congested and all the lifts where full, I was hoping for maybe a different issue. Got the van in this morning and put it on a lift, and sure enough, the flywheel is warped just enough that the tone ring is just out of reach of the sensor, and the van will start and run when the flywheel is pushed back into shape with a prybar. Thankfully, putting a flywheel in this van is not the most difficult project I've undertaken, for sure. I just don't look forward to having to buy a suspension/undercairrage lift >_<

[Alphabravo]

Just so everyone gets proper credit, jpb53 suggested it was a broken flex plate, which is what used to be called a flywheel.

[mrtinker]

Okay fellas... not to be too ignorant but.... How do you get a "broken" or "warped" flywheel in the first place? I thought that was a pretty heavy duty gear/part of the trany.

[tempfixit]

Originally Posted by mrtinker

Okay fellas... not to be too ignorant but.... How do you get a "broken" or "warped" flywheel in the first place? I thought that was a pretty heavy duty gear/part of the trany.

mrtinker, here is a pic of the flexplate/flywheel:



The flexplate is bolted to the crankshaft, which the torque converter for the tranny is bolted to and the starter gear also turns the flywheel for starting the engine. They are prone to cracking.

[thetandycollector]

Originally Posted by mrtinker

Okay fellas... not to be too ignorant but.... How do you get a "broken" or "warped" flywheel in the first place? I thought that was a pretty heavy duty gear/part of the trany.

Here's the "skinny" on how these break. First off, they can be caused by lots of things, this one I'm pretty sure we've nailed down to an engine performance issue that was causing the engine to "buck," AND the torque converter bolts do not appear to have been torqued down property when they where installed and they are backing out, causing a vibration and some light noise. That vibration is enough to destroy one of these uber-thin flywheel lookalikes. I have had bad or weak starters or improperly installed starters cause flex plate breakage, as well as transmission failure, lockup torque converter failure, or just simply a manufacturer defect, since these are essentially a coke can someone pressed into a round shape and bolted a starter to one edge

[RIP]

Originally Posted by mrtinker

Okay fellas... not to be too ignorant but.... How do you get a "broken" or "warped" flywheel in the first place? I thought that was a pretty heavy duty gear/part of the trany.

http://www.2carpros.com/articles/how...lexplate-works

[Alphabravo]

Originally Posted by thetandycollector

Hiya all,

I have a 1998 Grand Voyager SE w/2000 model eng/trans/computer.

Not to change the subject, but how was the eng/trans AND computer from a 2000 put in without mixing up the VIN #s and stuff on the computer? Wouldn't the computer scan show the VIN # from the 2000?

I'm looking to swap power trains from 2001 and a 2003 but hesitant to change the computers because of that. Is there somethng I'm missing?

Thanks!