01 T & C missing in drive range 3.8 engine

Got a miss in drive range. Not in Park. It does not miss all the time. Sometimes it does not even miss on going on an errand. Sometimes it does alot. If I am waiting at a stop light I feel it too, happens maybe 1 or 2 times at a 2 minute stop. Sometimes it's bad when driving but never as bad at a stop. MPG is bad. Worse if AC is on, not as bad when off. I have no codes. Any help would be great! Thanks!

New tune up, alt., battery, PCM, transmission, 78,000 miles, etc..

It did this before I had any work done to it but wasn't nearly as bad as it is now.

new rad/thermo/etc too

Sounds like a miss with any load on the engine. I would start with checking resistance on plug wires or just replace. Check all connections in the ignition circuit for security and corrosion.

What all is involved in checking the ignition circuit for security and corrosion? The wires where replaced about a month or so ago, still had this problem before and after replacing them. How can I check the wires? I had the dealer replace them last time. Thanks

Since changing the plug wires and I'll assume the plugs didn't effect the miss I would assume the problem lies elsewhere. It can be tough to find the smoking gun on an intermittent miss especially if you're not seeing codes. What can be said is it's either the ignition system or the fuel delivery system.

The ignition coil and the powertrain control module (PCM) are the only components left in the ignition system. Problem is they are pricey at $80 for a coil and $300+ for the PCM so you want to do everything possible to make sure the part is bad before you change it. The best way to do that is to connect a fancy scanner with an oscilloscope and fancy software. Most of us can't do that and many dealerships and shops have the equipment but, aren't proficient at using it. Short of that, there's still some checks you can make:
> Disconnect the power connector on the coil and and make sure the pins aren't corroded. Spray it with contact cleaner and reconnect. Do the same with the PCM. Make sure you disconnect the battery first.
> Connect a timing light to each of the plug wires and watch for a skipped flash of the light. This will let you know which cylinder is producing the miss.

You can further narrow down the fuel system to the fuel injector circuit. The PCM delivers a pulsing voltage to each of six fuel injectors. You can try this:
> Make sure all the injector connections are clean and tight
> You can monitor injector pulses using a test light or just by feeling for a continuos click at each injector
> Try using a can of injector cleaner or get the injectors flushed at a shop

Just to be sure, I want to be sure you're not actually sensing a cut-out and not a miss. A miss produces a slight jerk felt though the seat or steering wheel. A cut-out is a deep sag or stumble from the engine that jerks the whole van. It's when the engine momentarily looses all ignition then restarts on it's own. Which are you seeing?

Boy I'm glad you brought that up. I does feel like a cut out. Like the whole engine dies for just a slight second and is fine again. And yes I feel it through the whole van.

I am noticing that when I take off sometimes I am getting alittle hesitation now. I ran a few errands today with and with out the AC on and really didn't notice much difference in the missing/cutout, sometimes I do though. The PCM was replaced about a month or so ago. I will go get the cleaner.

In that case crankshaft or camshaft position sensors is where I would start. They are a common cause of your symptoms. First I would look them over and make sure the connector is tight and clean. Luckily, they are fairly cheap at around $25 at the dealership and I would make sure to get OEM sensors. They appear to be more reliable. I would lean toward the crank sensor first. Seems to be the more common of the two to fail. Easy to change. One bolt, one connector, done. The new one should come with paper on the tip. This paper acts as a spacer to make sure it's spaced correctly internally.

Boy am I glad you clarified that. You're more likely to get a code if you have a problem in the ignition. Your lack of a code was giving me some big doubts. These sensors are designed to throw a code but, more often then not they fail without generating a code. Now it makes more sense.

These sensors are the main inputs to the engine computer (PCM) to let it determine correct engine timing and air/fuel scheduling. This will effect mileage and acceleration.

Just so you know, the ignition coil has been known to do the same thing but, I would say the sensors are more prone to cause the engine to cut-out, plus at around $80 for a new coil I would go with the sensor first. I would still go ahead and inspect and clean the connector on the coil.

http://www.autozone.com/az/cds/en_us/0900823d/80/1a/40/96/0900823d801a4096/repairInfoPages.htm 99 is the closest Autozone would let me get. Should be at least close to the same procedure.

I looked into the sensors today. Am going to replace the crank first as you recomend. I was wondering, when I turn the key on but not start the engine I notice on the information center that after 10 seconds the malfunction indicator light flashes 10 times. It does not do this if it's started, does not come on while driving and have no codes. Is this normal? Just wondering, was thinking maybe it could be saying something. And about the crank sensor, is it a simple switch? I was driving around today and did not feel any miss at a stop, maybe alittle during driving but barely noticable. This was with the ac off of course.

You are full of surprises! I am not completely sure but I think a flashing MIL light with the key on indicates a problem with the PCM. I've combed the net for an hour looking for concrete info but saw none. I remember seeing this posted on a forum about a year ago but, can't find it. Sorry, I'm just not sure. Might ask your dealership or an experienced shop.

What you should see when you turn the key on is the MIL light (Service Engine Light) flash on for 2/3 seconds then turn off. If this isn't happening this is another indication of a PCM problem. Don't recall the code but are you seeing the "end of test code"? If not, that's another indication. Same for the "battery disconnected" code. Try disconnectiong the battery to induce the code.

The good news? If your PCM is less than 8 years old and you have less than 80K miles on the van, it is covered under a special emmissions warranty. You get a new one free. The bad news? If thats not the case a new PCM will cost around $300.

If you're not using a scanner to read your codes you might try going to an Autozone and have them connect a scanner and read them. It's free. I would put the sensors on hold till you get this issue settled. I've posted another thread hoping someone can tell us what it means for sure.

EDIT - Just noticed this is a new PCM. Check with the folks who installed it.

Is the PCM the computer box by the battery? If so I just replaced it, it was $1000.00 just for the computer box. If not, what is the PCM?

If you have an owners manual for your van that is an ideal source to tell you what the check engine light is "supposed" to do during a KOEO (Key On Engine Off) ignition cycle. I would look there first.

Also, there are sometimes manufacturer specific codes that will NOT show up on in Global OBDII scan mode.

I can't remember right off the top of my head where the PCM is located on this specific vehicle. One thing that I would reccommend if you want a good information source on your van is to buy a subscription for it at www.alldatadiy.com. I think that the first subscription (1 year) that you buy costs $25, but then every subscription for any vehicle (or subscription renewal) after that is only $15. This is generally about the price of a Hanes or Chilton's manual but contains TONS and TONS of very useful vehicle specific information....which is more than I could ever say of one of those rinky-dink little manuals. This is the factory specific information that many professional shops use.

Good info plus...someone brought up this point: are you sure this is a Mil or Service Engine Soon light and not just a maintenance due light (not sure there is one on an 01)?

The PCM is mounted on the drivers side fender wall outboard of the battery and the PDC (fuse/relay panel). Just found one on the internet for $354 for your van. They are cheaper elsewhere. Sure wish you would have come here first. http://www.autozone.com/az/cds/en_us/0900823d/80/1a/3f/5c/0900823d801a3f5c/repairInfoPages.htm