How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask ironmike Your Own Question
ironmike
ironmike, ASE Master Tech L1
Category: Mercury
Satisfied Customers: 3382
Experience:  Ford certified 30years exp
11302663
Type Your Mercury Question Here...
ironmike is online now
A new question is answered every 9 seconds

1999 mercury villager: hill..runs rough..the check engine light comes

Customer Question

I have a 1999 mercury villager. It idles rough and when you give it gas to pull a hill or just to go faster it really runs rough and the check engine light comes on and has little power. Any ideas?
Submitted: 5 years ago.
Category: Mercury
Expert:  ironmike replied 5 years ago.

ironmike :

greetings,

ironmike :

you may have a misfire. That would cause no power and the check engine light to come on.

ironmike :

has this vehicle been tuned up?

ironmike :

how many miles?

ironmike :

most parts places will scan a vehicles computer for free

JACUSTOMER-qn4kgahe- :

No It has not been tuned other than spark plugs and it has 165000 miles

ironmike :

if you get the vehicle scanned for trouble codes we will have some diagnostic direction

ironmike :

these have spark plug wires and a cap and rotor that can fail

JACUSTOMER-qn4kgahe- :

This happened awhile back and it had been raining. I was told to check the plugs, distributor cap, etc. If that wasn't it, it might be an injector problem.

ironmike :

if this is a misfire we need to fix it soon

JACUSTOMER-qn4kgahe- :

Tonight it was not raining so I assume it is a misfire problem?

ironmike :

this can cause the catalytic converters to fail

ironmike :

rain could cause an issue if the spark plug wires are weak

ironmike :

rain or water makes a good ground, known to cause misfires

JACUSTOMER-qn4kgahe- :

Well thanks for your time. Your information was helpful.

ironmike :

A good test is when it is dry , spray the wires cap and rotor with a spritzer bottle

ironmike :

if they are weak it will start to misfire and you may see the spark jump to ground

ironmike :

these engine also can have bad injector plugs/connectors

ironmike :

heat makes them break and they get loose on the injector

JACUSTOMER-qn4kgahe- :

Tonight it was dry (NO rain) when it happened. The farther we drove the worse it got.

ironmike :

if you get the codes and if you have more information I will be glad to continue to assist

JACUSTOMER-qn4kgahe- :

OK...I'll see what I can find out! Thanks!

ironmike :

wires can fail dry too. If left alone a bad wire can cause the spark plug to foul and cuase the converters to fail

ironmike :

you are welcome

ironmike :

what did the spark plugs look like?

JACUSTOMER-qn4kgahe- :

looked pretty bad

ironmike :

was the tip white, black

ironmike :

If you pop off the distributor cap look for signs or arc cracks

ironmike :

the spark will follow the crack and not fire on a cylinder

ironmike :

that is a common failure for distributor ignition designs

JACUSTOMER-qn4kgahe- :

i don't remember color wise

ironmike :

if not codes and wire,cap/rotor look good we should do a compression test

ironmike :

you could check the injectors too, see if ach one gets a pulse. they make noid light kits for this

ironmike :

test light could be used

JACUSTOMER-qn4kgahe- :

I'll check everything out and try to get some codes and see what I find. Any specific codes to look for?

ironmike :

p0300 codes 301 etc

JACUSTOMER-qn4kgahe- :

ok...thanks!!

JACUSTOMER-qn4kgahe- :

Brother in law is bringing his code reader tomorrow...hopefully. I'll let you know what I find.

ironmike :

good deal

Expert:  ironmike replied 5 years ago.
I will be here tomorrow
Customer: replied 5 years ago.
Pulled the codes. Had P0325 and P0304. Changed spark plug wires today, P0304 went away and P0300 showed up. Idles very rough, especially when in drive. Found that 300 code is random misfire. Any suggestions on what to do now? Maybe distributor cap and rotor?
Expert:  ironmike replied 5 years ago.

I would have checked the cap when replacing the ignition wires. 304 is a misfire on cylinder #4 (300 is random misfire) and 325 is the knock sensor. The knock sensor is located under the intake manifold, not easy to replace. You can ohm the sensor out(500k-620k ohms) and make sure the circuits to and from the PCM are good. You will need a scanner to see the knock sensor and to make sure it is not causing the timing to retard. the misfire code and knock sensor code might be related. We need to make sure the injector connector has power and there is a pulse at the connector. Noid light or test light will work for this. If the cylinder is dead all the time you can pull the wire at the spark plug and test for spark. You can use a screwdriver with an insulated tip or spark tester.

graphic

if you did not replace the wires one at a time make sure again they are right.

graphic

Expert:  ironmike replied 5 years ago.
jump the injector connector with the test light or just plug in the noid light. One side should have power with key on and the other side goes to the PCM which controls the ground to turn on and off the injector.
ironmike and other Mercury Specialists are ready to help you
Customer: replied 5 years ago.
Thanks for all your help...replaced the cap and rotor and that fixed the problem. Still getting the 325 code on the knock sensor but it's running great now! Thanks again!
Expert:  ironmike replied 5 years ago.

I have seen a few asian vehicles(villager=quest) with knock sensor codes but no performance issues. The customers would leave it alone after finding the cost to replace.

thank you

Related Mercury Questions