George_Jetson

It is possible that you picked up a bad tank of gas, it is possible that the fuel filter is clogging up due to contamination. Have you checked the computer for codes? How long has it been since the last tuneup? and or course how many miles do you have on the car?

P0500 is the vehicle speed sensor, it is driven by a gear that is attached to the differential carrier. The code indicates that the computer is not seeing the signal from this sensor. BUT you also state that the car will not drive, so I assume that you mean it will not move forward. What happens when you place the car in reverse? Does it move then? If the car is not moving at all, then you need to look at the transmission. The ECM is generating the code because it believes that the car is in gear, and engine is running (and the RPM is responding to the throttle), but yet the ECM does not see the vehicle as moving. I would bet that there is no problem with the sensor, it is the fact that the car is not moving. Now I might have read you post wrong, but if I am correct about the car not moving at all, you need to start looking at the transmission. Start with checking the trans oil. What is the level? Is it pink and what does it smell like?

I'm to hear that we could help, I'm sure that you saved a lot doing it yourself.

I would think the fact that you are loosing comunication with the ECM, while the engine is acting up is the most significant clue. You should be able to comunicate with the ECM whenever the ignition key is on, (engine running or not, hot or cold). This is why I believe that you should look very closely at a electrical problem. Checking both the supplies, and grds, because the next logical step would be to open the ECM and inspect for any signs of dammage, and then replace. But this is of course expensive, so that is why I am stressing that both the supply and grds be checked closely.

Did any maint records come with the car? I would suggest pulling one of the plugs and looking at it, measure the gap, does it look like the original plug? If it looks like the original plug, and you can not verify otherwise, I would suggest doing a complete tuneup before trying to troubleshoot the problem. It is always best to start with the basics. I would also recomend buying several different extensions for your ratchet wrench in order to get at the rear plugs. They are possible to replace without removing the intake plenum.

Right when you shut it down, there should be a float charge (also called a surface charge) on the battery, it should read 13. +. so it sounds like the alternator is not running. If you have a battery charger, charge the battery and then take it down to the auto part store and ask them to test it. There could still be battery problems that would prevent it from taking a charge. A voltmeter can tell you some of the basics, but since many auto part stores have better diagnostic tools it would be a good idea to utilize them. Since they will check it for free, it is time well spent.

I do not understand what you are refering to with the 12v green light. If you are measuring 12volt right after shutting down the engine, that would be far too low. If it is 12 volt with the engine running, that is even worse. With the engine running, you should have a min of 14.2 to 14.8 volts. If you are reading only 12 that would indicate that the alternator is not putting anything out. After running the car you should see a float charge of close to 13 volts. So I would suggest taking the car to the auto parts store, and asking them to use their tester on it.

If you are interested in reading your own codes, there are several USB scanners that enable you to use a computer to interface with the car. These scanner will read codes, reset codes, and also display the values of the different sensors. Things like coolant temp will be displayed in degs and such. These scanners are much more versital than a basic code reader. Once you can read the code, and check the raw data, you then use conventional troubleshooting to determine whythe code is present. You can find these scanners on places such as EBAY, they cost the average of $50 to $60.

It doesn't sound like a hose issue in this case. The fact that you lose communication with the ECM when the engine starts to run poorly, points more to a electical problem. Once you have eliminated the 12 supply and grds, you should inspect the ECM. The fact that once it cools off, communication is re-established, and the engine runs well tends to confirm this. But before suggesting that you replace it, you need to confirm that the power is good. Make sure to measure the AC voltage because problems with the full wave bridge rectifier inside the alternator can really freak out a computer. Unless you place your meter onto the AC scale, you will not see some of these symptoms.

The dogbone mount helps control the engine torque, if it is worn, the engine will rotate along it's axis when torque is applied. This can cause several problems, such as the rubber hose connecting the throttle body to the MAF meter will flex more than it should (if it is old and cracked it will open leaks), the axle CV joints will be placed at angles that they were not intended to, for just a couple things. This is a issue with rubber engine mounts that is not isolated to transverse engines, longitudale mounted engines also have these issues, but the symptoms are different.

Yes definatly check the dogbone mount, the noise could be a vac leak due bad hose (as engine move, the hose also moves). So of course you also want to check hoses. Which sensor have you already replaced? I would normally recomend replacing both of the 1st sensors at the same time (bank1 sensor 1 and bank 2 sensor 1). You can get a visual on how much the dogbone is moving by opening the hood, and STAND OFF TO THE SIDE OF THE CAR. Have a friend place the car in drive, and WHILE HOLDING THE BRAKE DOWN, give the engine a little bit of gas. The engine will move, you should see the dogbone move also. Of course have the car parked in a spot where it is safe, in case it moves a little. Also stand off to the side for the same reason.

I would suggest checking the 12 volts at the ecm connector next. There are to 12 volt inputs, one is constant, and the other is present only when the ignition is on. I would monitor both, wait until the engine starts acting up. Also check the grds to the ecm (making sure to monitor it while it is acting up). I would also do the same at the OBDII connector (not that I think that is the problem, but I think that it may possibly reveal a symptom). If all that looks good, shut the engine off, remove the battery grd terminal, and then remove the ecm. Open it up and give a good visual inspection for corrosion, or signs of heat damage.

Check voltages at several spots, such as battery, alternator output, and some of the main fuses in the power distribution box. Check both DC voltage, and AC voltage. It sounds like a ECM problem, but you need to eliminate other possibilities before replacing the ECM. If there is any damage to the batter terminals, or any other odd things going on, Such as intermittent Tachometer, odd things with fans, or lights, make note of them. These might indicate the next possibility of what you should look at.

Start with cleaning the throttle body, and the IAC valve. Also clean the Mass Air flow meter. Check the condition of all your hoses. With time, the rubber hoses harden and split (normally near the ends). Do not forget the PCV valve.

I would suggest pruchasing a Hayes, or Chilton manaul, You can order one from any decent auto part store. They are written so that beginners can understand them and they have good ilistrations in them. They go into good detail, unlike the factory manuals that have very little explainations and would be of little use for a person that wants to learn. It takes time, but once you understand how the different parts interact it will seem much more clear to you.

I printed out both 94 and 95 wiring diagrams, along with one of the connector views, so that you could identify the pins. Unfortunatley the site is not letting me upload a word doc. If you PM me with your email, Ican send it to you direct. It is just slightly over 1 mb, and I think you will find it helpful.

Alldata shows different color codes??? Please look at the build date (located on the drivers door) it should tell you which month the car was built. I will then look up whichever year is is closer to. I know this may sound a little odd, but auto makers do changes mid-year. Your car may be wired as a 94

You're welcome, hope the plug swap goes well. If you find that the outside of the plugs are oilly, I would stop. That would indicate that the valve cover tube seals are leaking. And you will need to consider replacing the valve cover gaskets.

alldata shows either ND SK20R11 or NGK IFR6A11 with a gap of 1.1 mm (.04 in) you should be fine with either plug.

You have not stated the mileage, but I would suggest checking the airfilter, and under the rad cap (look inside to evalute the visual condition of anti-freeze). On some cars that have spotty service, it will be evident when you remove the cap. Also check for stickers on the windshield. If everything looks normal, I would do the next recomended service, and check condition of brake pads. When you remove the wheels to check the pads, give a good visual of the suspension. A lot of things like torn, worn rubber bushings will be evident. Check rubber brake lines, they should look dusty gray color. If the lines look dark (especially near the ends) they should be replaced. If you are just stating out with servicing you car, I STRONGLY recomend a good set of jackstands, or ramps. The jack that comes with the car should never be trusted for anything. Never put yourself in a position where any part of you could be caught underneath the car when it drops. Always keep yourself clear of the car when it is on any type of jack. It must be on a jackstand or good set of ramps before working underneath a car.

1.1 mm to 1.3 max. Even when they say that it is pre-gapped, it never hurts to verify. I personally put a Very light coat of anti-sieze on it, just enough to color a little over half the threads ( the half oposite the electrode). I have been worked on a lot of pre-cat engines, which I gave a reasonable coat. Since cats came out, I use much less. I have worked on engines where pulling the plug was very difficult due to corrosion, hence I always put a little bit on the threads. There are different views on this, so you will need to pick which you feel comfortable with.

Unless you have a well documented maint history of the car, I would suggest buying a manual, and then doing a major tune-up, service. The best thing that you can do for any car is to put in on a routine maint schedule and sticking to it.

That is a very subjective question. You will get a dozen different opinions, of which some will be valid. I would use NGK, I have used then plenty of times before without a problem. Whichever you use, gap them before installing. I would also use a very small amount of anti sieze compond on the threads. Make sure that it is a small amount because contaminates burning in the cylinders can damage the cat's.

I would go ahead and look at one of the front spark plugs, they are easy enough to inspect. I personally would be concerned about leaving them in too long.

I suggest looking for vac leaks, ie disconnected hoses and such. Get the idle speed down to where it should be, and fix the temp gauge. Once you get it to idle, you should be able to get a better idea of what shape the engine is in.