Rough Idle, P0300, P0135, P0155 AARG!

[Flooglebinder]

Hey Guys (and girls?)

I've had the usual problems with my 2000 Safari Cargo van...the rough idle and misfire that I was experiencing last year turned out to be caused by worn teeth on the distributor shaft, and the fuel pump died and was replaced...so now the gas gauge actually works. So those problems were fixed (YAY) but now I have a new problem...

Last week the van would downshift on inclines at about 55 mph or so, and the check engine light would flash. There would be a noticeable miss in the engine at this time. This would last for a couple miles and then the miss would go away, and the check engine light would disappear after a day or two. Then a few days ago, it did the usual downshift-miss-check engine light routine and it didn't go away. The miss/rough idle is "all the time" now.

I pulled a 0300, 0135, and 0155 code off with my scanner, so I replaced the post-cat O2 sensor...I also replaced the cap and rotor, and air filter. Problem still there...rough idle right from start and misses throughout rpm range. No "rich" odor from exhaust.

When I was trying to diagnose the problem last year with the occasional rough idle and misfire, I replaced the cap and rotor, plug wires, ignition coil, plugs, EGR, and when the fuel pump was replaced the fuel filter was replaced at the same time.

I don't want to throw parts and dollars at this thing again. Anybody got ideas about what's going on here?

Thanks! And btw, great forum! I wish I'd known about it last year...

[JPDVAN]

Hi Flooglebinder,
Did your scan tool give you a discription of the codes? See below if not.
If the O2 sensors are high mileage (+100k) I'd replace em for that reason alone.

P0300=Random multiple misfire
P0135=O2 Sensor heater circuit B1S1 (Bank 1 Sensor 1)
P0155=O2 Sensor heater circuit B2S2 (Bank 2 Sensor 2)
The "Check Engine" or "Service Engine Soon" (in the case of my 97) Flashes when the Air/Fuel mixture is rich enough to
damage the cat.

[redfury]

Been doing a lot of reading lately. From my readings, it's extremely likely due to your complaint that the distributor ate another gear. Seems that this is one of those problems that can be nagging until you find the right gear. Something isn't meshing right. One guy was replacing the gear on his distributor almost every 5 months. Check the gear type, you may need a different material for the gear to be made out of . There is some kind of alignment issue or lack of lubrication on the gears. I'd use a little moly grease or assembly lube when you put it back together if you find you need to replace it again.