p0301/p0302
RoB51988
10-20-2008, 03:13 PM
just replaced head gaskets and drove for a few days. Not engine light is flashing and getting p0301 and p0302 which means cylindars 1 and 2 are misfiring. What should I try to be fixing?
shorod
10-20-2008, 07:07 PM
What year and engine does your Taurus have? What have you checked so far (plugs, wires, fuel injector wiring, compression, vacuum lines, etc.)? There are a lot of things that it could be. Help us help you by narrowing down a few things.
-Rod
-Rod
RoB51988
10-20-2008, 07:54 PM
it's a 96 Taurus head gaskets just replaced, new plugs. I don't think it's blow by because there's no oil on air filter. I'm going to get a compression tester tomorrow.
What would I check for vacuum hoses. Also, would a mass air sensor cause this?
What would I check for vacuum hoses. Also, would a mass air sensor cause this?
shorod
10-20-2008, 10:40 PM
I wouldn't expect a MAF to cause two adjacent cylinders to report a misfire. I'd expect more of a random misfire or lean or rich condition to be reported due to a faulty MAF.
Were the plugs new just before the problem started? Why didn't you replace the plug wires at the same time? Since you disturbed the wires to change the plugs, maybe you didn't get a couple of wires seated tightly.
-Rod
Were the plugs new just before the problem started? Why didn't you replace the plug wires at the same time? Since you disturbed the wires to change the plugs, maybe you didn't get a couple of wires seated tightly.
-Rod
RoB51988
10-21-2008, 04:14 PM
When I replaced the gaskets it buddy had some plugs he gave me and I just leftthe same wires. I replaced the wires today and now there's only one error code. P0301 now. So I'm going to try to change the coil tomorrow and see if that does the trick. Any other tips?
RoB51988
10-22-2008, 02:03 PM
Bad compression on cylinder 1, only 75 PSI. 115 on cylinder 2. 175 on cylinder 5. :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead:
shorod
10-22-2008, 10:10 PM
That's a bummer. I don't suppose you had the heads planed when you did the head gasket job, hunh?
-Rod
-Rod
LeSabre97mint
10-22-2008, 11:25 PM
Rob
Sorry to hear about the low compression! I'm glad you did the test. Now, we need to find out what is causing the poor compression. It's one of three things: 1. Rings 2. Valves 3. Headgasket.
If it's the rings a bit of oil added to the cylinder the compression will get better.
If it's the valves or headgasket oil will not much of anything to build the compression.
Also, I believe that the compression psi on each cylinder should be within 10% of each other so you may have problems with other cylinders too.
Dan
Sorry to hear about the low compression! I'm glad you did the test. Now, we need to find out what is causing the poor compression. It's one of three things: 1. Rings 2. Valves 3. Headgasket.
If it's the rings a bit of oil added to the cylinder the compression will get better.
If it's the valves or headgasket oil will not much of anything to build the compression.
Also, I believe that the compression psi on each cylinder should be within 10% of each other so you may have problems with other cylinders too.
Dan
shorod
10-23-2008, 07:42 AM
Dan's comments of adding oil made me think of another common problem when making compression measurements. Rob, you mention that you just got the compression tester. Did you read the instructions that say you should have the fuel injectors disabled and the throttle all the way open when cranking the engine to make the compression measurements? If not, that could potentially contribute to numbers that are all over the board.
-Rod
-Rod
RoB51988
10-23-2008, 09:36 AM
Ya injectors were unplugged and gas pedal was to the floor. The head may be cracked or warped or a bad ring. I think the car can int start with 70 psi so it's just barely there.
It's still drivable. I changed the thermostat and it says it's at operating temp, but opening the hood you can tell it's really hot. The coolant has only over flowed once in the past week but I was being kinda rough with the gas. So maybe if it take it easy it wont over heat. I dont know why its over heating though because theres a new thermostat.
But anyways, how long do you think it will last like this? And how would I add oil to the cylinder?
It's still drivable. I changed the thermostat and it says it's at operating temp, but opening the hood you can tell it's really hot. The coolant has only over flowed once in the past week but I was being kinda rough with the gas. So maybe if it take it easy it wont over heat. I dont know why its over heating though because theres a new thermostat.
But anyways, how long do you think it will last like this? And how would I add oil to the cylinder?
shorod
10-23-2008, 02:09 PM
I'd be surprised if anyone would even venture a guess as to how long this would last being driven in this condition. I assume your state does not have any type of vehicle inspections. If you are doing the work yourself, it probably wouldn't take long before the cost due to reduced fuel economy would outweigh the cost for you to repair the problem if it's a head or gasket issue.
One way to add oil to the cylinders would be to remove the spark plugs and carefully drip the oil through the spark plug hole.
-Rod
One way to add oil to the cylinders would be to remove the spark plugs and carefully drip the oil through the spark plug hole.
-Rod
RoB51988
10-23-2008, 04:02 PM
haha well I spent 250 at the most to change gaskets plus 50 hrs of my life il never get back. I got quoted between 1900 and 2500 for a mechanic to do it so I got a while.
I'll try the oil hopefully that gives it more compression and life.
I'll try the oil hopefully that gives it more compression and life.
LeSabre97mint
10-23-2008, 08:22 PM
haha well I spent 250 at the most to change gaskets plus 50 hrs of my life il never get back. I got quoted between 1900 and 2500 for a mechanic to do it so I got a while.
I'll try the oil hopefully that gives it more compression and life.
Rob
The oil in the cylinder is only a test. The oil will not last long when the engine is running.
Dan
I'll try the oil hopefully that gives it more compression and life.
Rob
The oil in the cylinder is only a test. The oil will not last long when the engine is running.
Dan
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