90 Caravan CV emissions?

I have a 90 Caravan Cargo Van. The state says it must pass their emmissions testing. The switch/on-switch/off test doesn't show any codes and the Miller code reader doesn't register anything either. I don't think a 90 is an OBD II, is it? Wondering if this cargo van does have the usual controls like an Oxygen sensor. Do you have and information?

Reply to
AHoudini
Loading thread data ...

If it did not pass (I am assuming) please post what readings were exceeded if you want any help.

Ted

Reply to
Ted Mittelstaedt

The 90 is NOT OBDII. That did not start until 95-96 models. Yes, it does have O2 sensors. Give the van a good tune-up and make sure it has a clean/new pcv valve. If you have not changed oil recently, give it a oil/filter change. Make sure the fuel is fresh and full and drive the van a bit before you get to the testing station. Make sure the engine is good and warm and MAKE SURE the air conditioner is OFF. Some testers will NOT turn it off during the test because if it is hot out, the cool air feels good. This can cause more emissions because of the strain on the engine. If it is hot out in your area, go in the morning( cooler air = better combustion ). GOOD LUCK

Reply to
Richard Benner Jr

None of this will help if the EGR valve is bad, and many times bad EGR will not set a code.

This is why I told him to post the readings. Please don't encourage people to throw away money on new plugs, etc. unless the emissions readings justify it.

Ted

Reply to
Ted Mittelstaedt

Ted, As far as posting readings, there aren't any readings. The check engine light will not flash codes and neither does the Miller code reader record anything. That car has not yet been to the state testing station. I don't think SDC communications maintained this van well. The Oxygen sensor was frozen badly in the manifold and the dist cap had pits. So, I am tuning it up with new plugs, O sensor, wires, cap and rotor and air cleaner. I've run into a problem in that I can't find a place where a new PCV valve will fit. This one only seems to have a rubber pipe running from the head cover to the air cleaner.

Al

Reply to
AHoudini

Then either something is *very* wrong with the engine control computer, or neither the flash code procedure nor the code reader is being used correctly (Or, for that matter, the "Check Engine" bulb is burned out). The correct procedure to obtain flash codes is:

With the engine off, switch the ignition key on-off-on-off-on, leaving it "ON". Do not go to "start", just "on" during this procedure.

Watch the "Check Engine" or "Power Loss" light. It will turn on, then go off, then will begin to flash-out any trouble codes that have been stored. For instance, if it flashes:

flash flash flash

flash flash flash flash flash flash flash flash

flash flash flash flash flash flash flash flash flash flash

Then you have a 12 (one flash followed by two) a 35 (three and five) and a

55 (five and five). 55 means "end of codes" or, if by itself, "No codes stored. Check the codes and report what you find.

Be sure to use a Mopar, NTK, Napa Echlin or Standard BlueStreak O2 sensor, and NOT a Bosch, or you'll just cause yourself more problems.

Which engine have you got? The 2.5 litre 4-cylinder or the 3.0 litre V6?

DS

Reply to
Daniel J. Stern

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.