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2000 town and country
09-25-2014, 10:09 PM
Post: #1
2000 town and country
Hello all,
I have a 2000 town and country with a 3.8l. It runs like crap but shows no engine light. When I pull the injector wires to check for a difference in how it runs, it will trigger the engine light. The problem is is that when I pull the front 3 injector wires, the code says that I have open circuits on #'s 1,3,and 5 cylinders which are actually the back 3 cylinders. The rear injector wires trigger #'s 2,4,and 6 which are actually 1,3,and5. I have a parts van and have changed absolutely everything including the PCM and entire fuse block. No change. Number 6 plug is always wet even when swapping injectors to different cylinders and it is hitting on that cylinder. I had it on a shop scanner and shows everything ok. Now, before I forget; this thing hit a bear and damaged the drivers side a little. The only structural damage was the headlight bracket and all has since been repaired. It ran fine before the hit but it sat for several months before the repair. Would old gas affect just 1 cylinder? I also checked the entire harness for melting or damage. The injector wire thing seems bizarre to me but maybe that's normal, I don't know.
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09-25-2014, 11:44 PM
Post: #2
RE: 2000 town and country
I have one of these mini vans so I will have to go take a gander in the daylight to confirm 1-3-5 in the front or back. What I can tell you is if there are no codes the next thing to look at with your scan tool is RPM at idle and O2 readings to see if the mix is off a bit. IOW, not far enough off to set a code. Poor idle due to a worn IAC (idle air control) might be worth looking at especially if the idle is below 600 RPM. The other thing is since the car has tangled with a bear something might not be straight so maybe not idling rough but you may feel it inside the car because the engine / trany is not alinged properly with the chassis mounts.... or a bad CV joint is in your future.

Now I have to ask how you know it's firing on #6 if the plug is wet and the scan doesn't show a skip? Could it actually be a mechanical issue? (low compression) Could it be coolant on the plug after it sits for a bit? (pulling plugs on the rear takes time)

BTW, are you the same guy who had us on the edge of our seat with a long term project car a few years ago? (Mitsubishi if I recall correctly)
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09-26-2014, 10:50 AM
Post: #3
RE: 2000 town and country
There was no damage beyond the headlight mount other than the PCM was knocked loose. I changed that with the donor PCM and the issue did not change so I changed it back. The shop scanner showed no misses or miss history as far as plugs firing and it has new plugs and wires. I ruled out compression due to the fact that it ran fine before the accident but I will check that to be sure. The plug smells of gas and so does the exhaust. I may have fouled the cat because once in a while it smells of rotten eggs but exhaust pressure seems pretty normal. I did pull the front fuel rail and cranked it over and the spray from the injectors was pretty uniform and seemed normal. When I did the tune up the rear plugs were dry and light tan. Number 6 was wet as it is now and 2 and 4 were whitish and dry. I may have knocked something loose in the fuel rail and it is affecting the front cylinders. I have sea foam in the gas now so I will see what that does. Yes, that was me with that Sebring a while back...I was hoping that experience could help me here but not so.
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09-26-2014, 05:56 PM
Post: #4
RE: 2000 town and country
My mopar van is a few years older but here's food for thought...

#6 injector is leaking or one of the vac lines is pulling fuel (or similar) from somewhere. (fuel pressure regulator?) You can do a quick check for leaky injectors with a fuel pressure gauge and watch for the PSI drop over a few minutes or hours. You could pull all the vac lines and sniff for fuel.

Let us know if that helps and I'll scratch my head a bit more.
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09-27-2014, 01:14 PM
Post: #5
RE: 2000 town and country
Ok, I decided to look for internal damage and started with a compression test and sure enough....0 psi in #6. Pulled the valve cover and cranked it over. All looked good there but I saw that the inside of the valve cover on #6 showed the rocker was hitting it. Checked compression with it off and it showed 35 psi. It looks like a bent a valve. The crazy thins is that the core support showed no signs of hitting the valve cover from the outside but must have and put the slightest dent and then flexed back out. I'm guessing this must be another zero clearance or close to it engine? Maybe carbon caught in the seat. Anyway, thanks for the support. As always, it is greatly appreciated.

Pat
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09-27-2014, 01:51 PM (This post was last modified: 09-27-2014 01:52 PM by Rupe.)
Post: #6
RE: 2000 town and country
Personally I would go another step or two before throwing in the towel. I can't think of too many things that would cause either end of the rocker to hit the valve cover because that means something is traveling too far. The other thing is to measure the resting height of the vavle stems. A bent valve will not fully seat and a dropped seat will show similar so easy to pick out against the next cylinder. You can visually check the push rod travel while cranking it before you take it too far apart. This will let you know if the lifters and cam are doing their job.

What I have seen (not on a MOPAR) is a sticky valve that doesn't return and if the push rod slips to the side on the next stroke that can cause the rocker to travel a bit more. It will also show up as a bent push rod most of the time. Could also bend a valve if it's real sticky. Of course the issue here is normally lack of oil changes, in which case the engine is fairly tired no matter how low the mileage is. OTOH, I have seen lots of these engines in both vechiles and industrial use and they seem to be rather bullet proof over the years. Matter of fact I have never seen a mechanical failure on either the 3.8 or 3.9 versions.

BTW, the 3.9 was widely used in stationary generator service. (power failures) The company I work for has sold hundreds of them and I only know of one that had an issue, which was oil fouling in a signle cyl.
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