2001 Xterra, running real rough, has 155k on it. The check engine light is flashing on and off. Still has the factory spark plugs in it. Could this be the problem?

replace no 6 injector
check injector wires and connections

Hi Sherri,

A flashing (check) engine light might be due to a direct engine misfire. This may be a Type A misfire due to the flashing engine light. This can be severe and can cause "mechanical damage" to your car. It can ruin your catalytic converter, though you might also want to have your spark plug and spark plug boots checked to see if they should be replaced as well.

It would be best to bring your car to a mechanic and have it checked.

Thanks,
Lyza

oxygen sensor bad, cataylac converter plugged

when the light flashes there is a misfire taking place check the plugs and spark plug wells look for black lines down the sides of the plugs

If your mechanic changed the spark plugs. Make sure he did a few things.

First make sure he used NGK plugs. I have seen other make plugs cause running conditions.

The other thing is make sure plug number 6 was changed. I can not tell you how many times I have seen shops leave that one cause it's to hard. That also can give you the ruff condition.

Last but not least, if the distributor cap and rotor and wires were not replaced, it may be possible that you could have a spark issue being loss. If you notice it more when conditions are wet, then it has to be related to those items.

Thanks Jay!

remove the coil pack and look at bottom of it if it shows any cracks coil is bad very common on these vans if you have a noid light check for injector pulse on #4 if you have pulse and good blue spark most likely the injector is bad you have to remove upper plenum to get injectors out let me know how you make out

If you dont have the proper spark due to a bad coil pack you will not get all the gas burned properly and your manifold will glow red.I would start with the coil pack.!

Check the coil pack. Same symptoms on mine. It went at 74,000.
You can get the resistance specs from a shop manual. I have been told the plastic engine cover traps heat and makes short life of the coil pack. I removed the top engin cover, cosmetic only after replacing mine. You will probably need spark plugs also they are probably fowled by now. If you have not changed spark plug wires in awhile in would not hurt.

The problem was corrosion on the contact points in the distribitor cap. I replaced the cap & rotor.

I have a car in the shop right now same thing - it is being caused by a misfire. Need a real technition to diagnose the problem (auto zone - advance auto can't diagnose the problem - only read the code)
mine was caused by a failing fuel injector. good luck