93 Grand am rough idle/misfiring

so the service manual covers all DTC errors , read that yet?
no engine told or what transmission is there or POST VIN and we tell you what's under the hood. there are 7 engines used
the VIN code 8th digit is engine code as are RPO list engine code


P0014 (SM says) 6 engines do it, VVT errors. and 8 degree error was found,

Exhaust Camshaft Position System Performance

rough = misfire, does the CEL glow running, (check engine lamp)
misfire has over 50 causes.
cold only misfire.
i guess you never scanned it or had it scanned, that it?
that be like first after a tuneup, ever get on in last decade?
lets say it was turned up and sparks now good.
and misfires. P03xx codes? we scan to learn that it has codes or not. codes means ERRORS< aka. DTC errors.
to see all errors takes skills, (some take 1,2,3, trips to see them all)
and looking in PENDINGS (and OBD2 term) for early errors.
you have new coils /plugs. good,

examples, the full scan of all live data tells me which path to follow.
what if the scan tool shows you
the ECU reads 150f all the time, (wrong)
and it really is 150f hot, bad thermostat. (or silly fail safe version latched open, omg....)
or it really is 180F and the ECT is bad. (IR gun tells me truth)
see?
just one example of misfire. there are many many more.
but cold misfire (not spark is:)
1: bad fueling. or bad engine, compression tests pass?
bad fueling has many causes. engine bad, stop, NOW.

a: fuel pressure wrong. not spec.
b: ECT reads low for hot.
c: injectors leaking or clogged (see "injector balance testing")
d: clogged fuel filter if engine bogs. (its NOT IN THE TANK)
e: other ECU inputs wrong, did i say scan it>?
f: FPR bad. (see a. above) it too is not in the tank yet.
h: MAP reads wrong, see e.?
I: ; more, ill stop now....

How to Fix error code P0300 for random misfires on your car ...

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Oct 15, 2010 - How to Fix error code P0300 for random misfires on your car ... amisfire (code P0304) on a 1999 Mercury Villager 3.3L · How to Fix error code P0500 ... I reset my codes and it ran fine for a couple of days, then I started getting ...

(code P0305) on a 1999 Mercury Villager 3.3L - auto repair

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Sep 7, 2010 - The vehicle is a '99 Mercury Village, 3.3L, with 150000 miles on it. The chief ... How to Fix error code P0300 for random misfires on your car ...

2000 Villager Misfire - Car Forums and Automotive Chat ...

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May 24, 2010 - 2000 Villager Misfire Villager Car Forums. ... i was told that the 3.3L engines of 1999-2002 nissan quests/ mercury villagers are INTERFERENCE engines! ... Hope the following may help, and I will post if my last fix works. ... I have a 1999mercury villager that is showing a random multiple cylinder misfire ...

Rough Idle - 2000 Mercury Villager - RepairPal

repairpal.com > Questions > Mercury > Villager > 2000 Mercury Villager

Repair the code issue, because your Villager has OBD-II which is a very helpful Diagnostic system. Upvote (4) ... My 1999 Villager was running poorly; rough idle, lack of power at highway speeds and the engine problem light indicated random miss-fire, etc. I had new spark ... Have code po306 cylinder 6 misfire detected.

P0301 - OBD-II Trouble Code - RepairPal

Check the coil packs or individual coils, fuel injection flush at sears where they actually do a flush. Check fuel filter too.

Good luck

Generally speaking, code 35 is a problem with the idle air control valve.
The valve is mounted on the side of the throttle body and controls idle speed by how much air is allowed into the intake manifold.

Trouble code P0043 means: HO2S Heater Control Circuit Low (Bank 1, Sensor 3)Hex code 43 is for a misfire.

DTC 43 indicates a cylinder misfire, but does not specify which cylinder is misfiring. To pinpoint which cylinder is misfiring, you need a scan tool and get the "P" code, as you can see in the chart below. So it is quite possible you're barking up the wrong tree.


If you go to an Autozone they will scan the codes for you, if the CEL is currently on, and tell you the DTCs they find. That will get you closer to the problem.
I'm fairly confident that if you do a complete tune-up, spark plugs, spark plug wires, distributor cap and rotor, that the misfire codes will be taken care of. Be sure you read this, Dodge Ram 1500 Running Rough before replacing the spark plug wires, or if you have already replaced them.

Hope this help (remember comment and rated this)..

Have the DTC read and take it from there. But i bet you have a cylinder misfiring. Once you get the DTC read it will lead you to the problem and you can tackle the job from there. It usually is a pretty easy fix.

all the codes you have are all related to the fuel trim, this problem needs to be looked at with a european capable scanner for futher tests sorry.

iwould say try some octane booster sounds like poor quality fuel p0300 is a multiple misfire so start with that and i believe vettes are supposed to run 89 or better octane

What happens when you unplug and cap the vacuum line at the EGR valve? Does the problem go away? Before doing this does the car idle rough? If so perhaps the EGR is stuck open...