Hello all, this is my first post. I have a 2003 grand caravan sport with a 3.3l and 81,000 miles on it. The other day cel lite came on and dropped codes p0108 and P1299. It was running rough and idled poorly missing and bucking all over the place. Since I had never put plugs or wires on it I went ahead and also put on a new Map sensor. Reset/cleared codes drove it and when I got about 10-15 miles on it the cel lite back on again, same codes and same condition. This time I could not clear codes until it cooled way down later that night and then it cleared codes ok and ran pretty well, except above 4000 in park when it falls all over itself again missing and bucking. Took off throttle body and cleaned it throughly and took off IAC motor to clean it but they all were very clean already. Same thing and same codes again today on way back from work. P1299 and P0108. I need someone to point me to some problem areas that would drop codes like this on a 03 gcv sport with a 3.3.
Also have replaced about every vaccumm hose I could find none were bad or broken. I can not find a vaccuum leak spraying everything with carb cleaner. I have a harbour freight scanner with freeze frame data but really do not know what I am looking at. Thanks for the assistance.
Dalton

 

i would check all air hoses and such, as these vehicles (i have an 02 se with the 3.3) monitor the vacuum on everything including the gas tank. if one is off, broken, or cracked it will leak and throw a code, but i doubt it will cause that big of a drivability issue. if it runs ok cold, and starts running rough at operating temp. i would say its a sensor going bad. when it is cool everything is contracted and working fine, then as it warms up it will expand, possibly enough to open up a tiny break in the internal wire of the sensor, thus causing an open circuit. i would recommend finding the internal resistance values of each major sensor, warming up the vehicle, and testing them with am ohm meter one by one. i would say a crank positioning sensor, possibly a coil pack. im sure someone will chime in to correct or support me, but that what i would do. good luck.

 

Thank you for the guidance, today I took out and replaced the PVC valve just for grins no help, checked the hoses to pvc and every where else on that engine and I truely find no leaks. SPrayed carb cleaner around intake and throttle body but no change or drop in RPM. I am leaning to either that TPS switch bad (which as far as I can check out with a volt meter) is ok voltage/wiring wise or a weird vaccumm leak that is only present when the engine warms up. Don't know still scratching my head!

 

id say its a bad sensor then, cause vacuum leaks dont randomly appear then go away.

 

Also check the wire harness around the rear cylinder head,see if they any wires that may have welded together.

 

I will check the wires around the rear head tomorrow when the sun comes up. What wires and where abouts on the rear head? Here is the update, I checked the best I could the voltages on the map and tps with a voltmeter and it was ok, r and r the pvc to clean and check it was ok, replaced the tps and it changed things a little bit. I now get a p0172 (after driving around town for 15 min)and a pending p1299 but scanner said only one code p0172 but freeze frame said p1299? I have taken off throttle body, iac motor and cleaned same thing. It misses terrible in park reving it anything past about 4000 on tach? On the road I can punch it and take it all the way up to 6000k and it pulls strong? It has a flat spot right off idle but not always. I have checked and rechecked all over this van for vaccum leak and found none. If I were to post the freeze frame data from my scanner, can somebody interpert it for me? Also what bank is bank 1 that is running rich ie p0172?? I am running out of ideas now. Thanks for any and all help.

 

Can you tell me about the area around the rear cylinder head that you are talking about? Do you mean the wires that run underneath the power steering resevoir? Thanks for any pointers that I can get because I am all out of ideas at this point!

 

Thats right, around the p/s resevoir and the exhaust too.

 

I finally was able to get the p/s reservoir off and then the coil pack and bracket. THey were soaked with oil from the p/s reservoir leaking. There looks like about a million wires right there in that spot. Is there any one in paticular that seems to be the most likely culprit for melting together? Can I spray brake clean on the coil to clean it off? Thanks and I will keep everyone posted as to what I eventually find out. Thanks again

 

You may need to open the harness and inspect the wires.