Question about 2005 Pontiac Grand Am

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P0302 and low coolant

I have taken my car to 2 different mechanics who have charged me to fix/replace varies parts but it has not fixed the problem. It started with a low coolant warning. I fill it up and the following week it is low again. I do not drive very much (I only have to gas up my car once a month). Then the car started to jerk when I started it. The first mechanic thought it was the thermostat, so we replaced it. He said he checked my coolant hoses and tank and did not find a leak. The second replaced several other parts, which I later find out have nothing to do with either problem. So I took it to AutoZone and finally got a read on the jerk problem. It came back P0302. I do plan on taking it to a 3rd and different mechanic but first I would like to know if the P0302 and the low coolant are related. Since I have been dupped twice already, I do not want to have to pay for things not related again. Can anyone help me? Thanks in advance

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Hi there:

DTC P0302 - Misfire Detection Monitor - Cylinder 2 Misfire

A misfire is nothing more than a lack of combustion, which can be caused by poor fuel quality or metering, low compression, lack of spark or unmetered air entering the engine. There are other possible, less obvious causes as well, such as uncommanded Exhaust Gas Recirculatin (EGR), flow.

Other possible causes:
* Fuel injectors, related wiring, sensors and computer issues
* Running out of gas, or poor fuel quality
* Evaporative emissions system (EVAP) concerns: fuel vapors leaking into engine
* Incorrect Fuel Pressure
* EGR system concerns: leaking EGR valve or restricted ports
* Base engine concerns: low compression, valve train problems and timing issues
* Ignition system concerns including, but not limited to:
- Faulty spark plugs
- Faulty coil or related wiring
- Ignition module or related wiring issues
- Ignition related sensor faults or wiring issues

Hope this helps.

Posted on Apr 29, 2013


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SOURCE: 2001 Grand Am GT - RPMS bounce, car jerks and stalls

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SOURCE: Car not running on all cylinders

the first thing that comes to mind is ignition system faults. Are the spark plug wires connected properly, in the right firing order? Has work been done on the distributer, or the engine head, recently? Ignition timing can be 180 degrees out, and the engine will still run, sometimes. If it is not the ignition system, the next most likely culprit is the head gasket, which seals the head to the block of the engine. If this gasket is breached seriously, it can cause a cylinder(s) not to fire. Is there water in the oil, as evidenced by a thick, white foam? Is there oil in the coolant? Either of these are symptoms of a leaking head gasket. 
Basically, one cylinder isnt firing for one of a number of reasons. The most common cause is an igntion fault. This will cause the engine to feel and sound "lumpy", and the power would be greatly reduced. The best way to find the cylinder which is responsible is quite simple but care must be taken. Firstly if you hate electric shocks as much as I do, find a proper pair of electricians insulated pliers, and even some decent rubber gloves if you can aswell. Start the engine, and one at a time, use the pliers to remove a lead from the top of one spark plug, if the engine almost stops, or gets worse in any way, it is not that piston which isnt firing. Repeat the proccess, one at a time, you will know which piston ISNT firing when you remove the plug lead, and there is no change in the engine sound, this is your defective cylinder. Its just a case then of looking at the condition of the spark plug and asessing the cause of the misfire before carrying out repairs. BEWARE:- THE LEADS WHICH CONNECT TO THE SPARK PLUGS CARRY SEVERAL THOUSANDS OF VOLTS - HENCE RUBBER GLOVES AND INSULATED PLIERS 

Posted on Mar 05, 2009

  • 1 Answer

SOURCE: service engine soon light keeps coming on. Now low coolant light

I would start by doing an oil change myself so you can examine the oil and look for water/antifreeze in it. You will be able to see it separate from the oil and you can smell the antifreeze. If there is then you have a leak between the water jacket and the heads somewhere. More than likely the LOWER intake gasket is leaking into the head. You said they replaced a gasket but was it the UPPER or LOWER? If it was the LOWER did they use RTV in the correct areas? Did they torque the intake bolts to the correct pressure and install the bolts correctly? I know you don't have these answers but these could all be part of the problem. It may be leaking more at #2 cylinder and causing it to foul more than the others. Also just because a mech pressurized the coolant system and didnt see any change in pressure (hopefully he wasn't just looking for visible leaks) the issue may not happen until the engine is hot, as metals behave differently when heated, especially aluminum which the LOWER intake is made. Have a mechanic or mechanically inclined friend (gearhead) remove the #2 plug wire, then kick the engine a few times without starting it, enough to let any fluid get into the chamber, this would include gas btw. Then remove the plug and look for any wet residue on the plug, gas will evap. quickly, antifreeze/oil won't. again try to smell the residue and if necessary, lightly touch some to your tongue, antifreeze has a sugary sweet taste that is easily detectable. Remember any time you are working with chemicals such as waste oil and especially anti freeze, minimize spills and clean them up quickly and completely and place the spent fluid in a sealable container and take them to a collection center for disposal. Waste oil is a carcinagin (cancer causing) agent and antifreeze (glycol) new or old will kill any animal (child, dog, cat,etc) that ingests it. Many auto parts stores and some other retailers that sell oil and antifreeze will take your wastes if you bought the replacement fluid from them, check before you buy.

Posted on Apr 04, 2009

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SOURCE: Pontiac Grand AM 2001 - How to reset the warning lights?

step on your gas petel 3 times with the key in the on postion but not started, you will hear 3 beaps then your done only works on 1999-2005 grand ams

Posted on Oct 03, 2009

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if (window.showTocToggle) { var tocShowText = "show"; var tocHideText = "hide"; showTocToggle(); } 17704/P1296/004758 - Error in Mapped Cooling System Possible Symptoms
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