QuestionQUESTION: i have a 2002 town and country 3.3 flex fuel (only use unleaded gas. for about the last year and a half it has been having problems. at firt it would just stall. i could throw it in neutral and restart it no problem. never gave me a code. so i changed plugs still happened looked at maintenance schedule and replaced o2 sensors now i got a code o2 sensors not switching not that big a deal. then i discovered that while it was dying i could pump the pedal and bring it back to life. thought maybe the throttle position sensor. replaced that. still a problem though. i decided recently to take it on a long trip just to see what i could get to happen. in the mean time i also changed my spark plug cables. anyway drove it two hours to my destination with not much of a problem. the on board display did state i was getting around 20 mpg was nearly out of gas when i got there. it did stall once while there got a new code p320 man i was excited to get something new. although driving home my display said i was getting around 15 mpg when i got home though i had nearly 1\4 tank more than driving down. i have been suspciouse of the computer but just tired of dumping money into parts any help?
ANSWER: That 0320 says there is a poor signal/no signal from the crankshaft sensor. That would make for poor running. So it would be reasonable to replace that. It is located at the seam between the engine and the transmission, on the back side of a flange that you will find there on the side of the engine near the firewall. You will want to turn the wheels to the left, then raise and remove the passenger tire, then from underneath feel for the sensor which is located just above the surface of the transmission housing where it is bolted to the engine (10 mm socket) and it has an electrical connector. If you remove the bolt it comes out of a hole for change-out. You put the new one in and press its paper-covered tip against the engine flex plate edge that it senses. Holding it in contact you tighten the retaining bolt to maintain that position.
I hope this solves the problem.
Roland
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QUESTION: well replaced crank sensor is worse than ever. starting to see trend i do remember the lady @ autozone once said the odb said it was a Mexican car does this matter does it take different parts?
ANSWER: Did you press inward on the sensor until you felt the tip of it come in contact with the edge of the flex plate? If not, then loosen the screw and retry it. Without any other code, my suggestions would be to clean the throat and butterfly plate, and side air passageway at the throttle body. In addition, I would check the egr valve for possibly sticking ajar which cause poor idle/stalling/poor starting. Here is a what I sent to another owner of the same engine on this subject:
"My immediate suspicion is that your egr valve is sticking slightly ajar which will cause the engine to falter/stop at idle speed after slowing down. The valve is located near the throttle body air intake at the end of the engine, mounted in pipe that recirculates exhaust gas from the rear cylider bank exhaust pipe back around to the intake manifold. The exhaust gases have some fumes that can plate out a crud on the valve stem and thus keep it from closing tight when you are at idle. That makes for a too lean mixture so the engine stalls. The valve proper is mounted horizontally with the stem visible in a space between the body of the valve mounted on the pipe and the round top of the valve which is flanged and so if you look carefully you will see a metal rod (stem of the valve) with a slot around its circumference. You can take the tip of flat blade screwdriver and insert it in the slot and then lever the valve back and forth to check if it is moving freely (against spring action in one direction) or not. If it doesn't seem to close easily with the help of the built-in spring, then I would spray the base of the stem with solvent from a pressure can (such as WD-40 or carb cleaner) while moving the stem back and forth. Then see if that solves the issue."
I hope these will correct your problem. Other than waiting for another fault code I can't suggest anything else to try.
The 11th digit of your vin would be "U" if it were assembled in Mexico. I don't believe that makes any difference in the part replacements or its life story.
Roland
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QUESTION: my van does not have an erg valve
AnswerI wonder why that is, because the '02 shop manual I have shows there to be one.
QUESTION: here is something i found though after dying and not always but most of the time the fuel pump relay and the asd relay begin clicking if i try and start it right away i can usually get it going guess that's how I've been driving like this for almost a year. but if i don't try and start it right away it's no good just won't start unless i shut the key off for a couple min. i discovered pulling the fuse for the fuel pump makes the clicking stop and also disables my ability to get codes from my gauges buy turning the key a couple times also my mps over head display reads -- i seem to think it is also disabling the pcm if i reinsert the fuse i can restart the van. i tried unplugging the wires to the fuel pump but it still clicks the only other way to get the clicking to stop is to one shut the key off for a couple min. or to pull the ignition fuse guessing these are the same. i am starting to really believe my pcm is hurt just looking for your experience/advice
ANSWER:
Hi Amdy,
I usually associate a relay's repeated 'clicking' as a sign of a low voltage situation at the relay actuation coil circuit. That could be because of a weak battery or battery terminals/ground connections of the -clamp's wires that are loose or corroded. So I would suggest you look into all those connections.
Of course pulling the fuel pump fuse (is that #17?) is going to shut down the pcm as that fuse also powers the pcm and therefor also the data needed by the overhead.
The issue of time delay between the stall and when it will restart might well be related to the 0320 code. Although you say that replacing the crank sensor didn't solve your poor running problem, it may have in eliminated this time-dependent restart issue because when the sensor is beginning to fail it will recover in minutes by letting it cool down. So there is an explanation for all of your symptoms.
I don't think you have found the real cause, but check all the battery clamp/ground wire connection as a start. And try cleaning out the throttle body throat/butterfly plate/side air passageway as I suggested earlier. Also measure the battery voltage when the relays are clicking repeatedly to see whether it is low.
Roland
PS I found your follow-up in the "pool" to which Kevin referred it.
