Head Gasket Failure?

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I cranked up my 94 Mustang this morning and I smelled gas and noticed smoke coming out of the exhaust. The car was idling a little rough and when I accelerated, it hesitated and ran poorly. I pulled over to a service station and checked the oil and water and they both looked normal. The attendant thinks it might be a blown head gasket "on the exhast side". I had a blown head gasket with this same car about five years ago. But, it had classic symptoms of oil and water mixed together and very white smoke with water coming out of the exhaust. Now, the smoke isn't quite as white and appears to have a slight bluish tint as if it were burning oil. However, there were some water droplets on the exhaust pipe, but it had only been running about three minutes.

I'd really appreciate it if someone could answer any of the following questions:

1. How can I tell if I have a blown gasket for sure? If it's not a blown head gasket, what else could it be?

2. Should I drive it to the mechanic, or have it towed? I don't want to risk additional engine damage if that is a possibility.

3. Should I use the same mechanic who replaced the head gasket five years ago? I'm concerned that he might be using poor installation methods that led to the current failure.

4. Would it offend the mechanic if I inquired about his installation methods?
I've read several installation issures at http://www.aa1car.com/library/gasket_failure.htm

5. The car has about 120,000 miles on it. Would I be better off with an engine replacement?

BTW- The engine is a V6 3.8L.

Thanks,
Steve Smith

Mar 4, 2007 at 5:42 PM

NOS

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i 'll try to answer this for you. thoes 3.8 are known for there headgasket problems.
1. Most cars have condensation in the tail pipe anyway so they will drip water.
2. start the car stand behind it by the exhaust if the smoke has kinda of a sweet smell to it it is most likely a head gasket.
3. are you noticeing any coolant loss?
4. did the mechanic change both head gaskets or just the one that was leaking (poor pratice).
also if you look back at the years when ford started making the mini van windstar it had a lot of recalls on headgaskets . it was the same engine my friend.

first time around may have already did slit damage to your engine,but if it is not giving you any problems like over heating or any oil use you may think about fixing it. a new engine is too much money and a used one may just put you back where you are now. 8) NOS let me know what you find. Also if you have some doubt about your mechanic i would't reuse him stick to your gut feeling. but you have been driving the car five years trouble free.

Mar 4, 2007 at 6:11 PM

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Thanks for replying. I really can't smell anything from the the exhaust. The coolant is just a tad low, but that's not unusual for this car. I think it's got a small leak, probably in the heater coil . The coolant has not gotten so low as to cause overheating. The oil level is fine. I'm not sure if both head gaskets were changed or not. If the mechanic only changed one gasket, would that be enough reason not to use him again? What is slit damage? The mechanic's shop is two miles away. Should I drive the car to it?

Mar 4, 2007 at 8:47 PM

TAURUSWHEEL

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Take the car to a reputable repair shop, or better yet, to the local Ford dealer, have them do a leakdown test, it will confirm whether or not the headgasket is bad.. repeated failure of the headgasket is not unheard of.. as long as coolant hasn't found it's way into the bottom end, there's no reason to spend extra $$$$ on a whole engine,,, it's too bad Ford has such an issue with this motor, it's really a nice torquey design, also known for tearing up motor mounts... and completely trashing itself if the front cover gasket goes.

Mar 4, 2007 at 9:57 PM

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Thanks again for the reply. I took the car to our local Ford dealer. The good news is that it isn't the head gasket afterall. They said it was caused by a bad fuel injector and the cost would be $ 440 which includes a $75 diagnostic fee. They replaced the fuel injector and now they say the PCM is bad. They say the bad fuel injector caused a short in the PCM. This will cost another $440. I'm wonding if it might have been the PCM all along and perhaps they misdiagnosed it. Is it likely for a bad fuel injector to cause the PCM to go bad?

Mar 7, 2007 at 7:38 AM

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Ford tells me the PCM(part) is $ 320 and the rest is labor. AutoZone will sell me a remanufactured PCM one for $ 148. The Ford service manager says they can install the one I get from AutoZone for the same labor cost. Should I shy away from a remanufactured PCM? At this much savings, I'd rather get one from AutoZone unless the experts here thing that is a bad idea.

Mar 7, 2007 at 12:35 PM

TAURUSWHEEL

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Hey ,it comes with a warranty right??? Make sure it is the right calibration for your car, you'll probably need the calibration number off your engine,, it isn't that hard to install if you have some mechanical aptitude, just get some good instructions

Mar 7, 2007 at 6:45 PM

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I called one mechanic and he said it was better to let the dealership install the PCM because it had to be programmed. I'm going to buy the PCM from AutoZone and let the Ford dealer service dept. put it on. AutoZone said I should get serial number from my old one and they can use this to get the right replacement.

Does it make sense for a bad fuel injector to cause damage to a PCM? I

Mar 7, 2007 at 6:58 PM

TAURUSWHEEL

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As far as I know, the older obdI computers didn't have to be programmed or "flashed" they do need to "learn" to control idle, shift points, and so on... which is not a major issue.. same thing as if you unhooked the battery for a short period of time... an injector in and of itself would not cause a computer to fail,, however a fault in the computer program could cause an injector to appear bad,, ford computers are pretty hardy items, they're rare to fail, though not an impossibility, in order to arrive at the conclusion they did, they would have had to run a series of specific tests to arrive there..the serial # should do the trick

Mar 7, 2007 at 11:30 PM

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What would you so in my situation? If the mechanic mistakenly thought the fuel injector was bad, when it was just a faulty PCM all along, I'm going to be out $ 440. Plus they want to charge me for reprogramming a PCM that probably does not need to be reprogrammed. Is it possible for me to know if the fuel injector was really bad in the first place?

Mar 8, 2007 at 7:57 AM

NOS

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The answer to you question is yes.
it is very possible for an injector to take out a PCM.
all the injectors have power running to them and the cam sensor is what triggers the ground to make it work throught the computer.
if the injector shorts to ground it can go right to the PCM. I have see it happen before. 8) NOS that is still bad but better than a head gasket.

Mar 8, 2007 at 8:21 PM

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Thanks again for the reply. I feel better knowing that it's plausable for a bad fuel injector to damage a PCM. I've had some bad experiences with auto mechanics in the past and I tend not to trust them. That's not to say they are all not trust worthy. It's just hard to find one who is both honest and competent. That's true for any type of service, not just auto mechanics.

Steve Smith

Mar 9, 2007 at 8:24 AM