MX-3.com

Hi everyone,

Just been working on fixing my friends 1997 Eunos 30x (V6), and have spent the day trying to get it running properly. I have discovered that the coolant temperature sensor seems to have really low resistance all the time (at operating temp it is way off from what is said in the online service manual on this site!). At operating temperature the resistance is about 0.7k-ohms, while when cold it is much higher at about 1.5k-ohms. It behaves normally, except that the online service manual says it's meant to be about 1.7k-ohms at least while at operating temperature... dud sensor/wrong sensor? I really can't work it out, and don't exactly want to spend $47 on a new one if it's actually normal...

Another thing is the distributor. The rotor is completely pitted and has carbon deposits all over it, which I have sanded down with some fine sandpaper. In the case of the distributor cap, all the terminals had about 1mm of white buildup on 3 of the pins, which i was able to flake off with a flat screwdriver. The centre pin on the cap is extremely worn down with solid white and carbon buildup all around, which has also melted part of the centre part of the rotor. Obviously this sounds like a replacement job, but I have been unable to find any equivalent part and no parts resalers seem to have them in stock (they only have complete $500 distributors...). Is there another particular car model that uses these same distributors? I have noticed they are mitsubishi parts, so I would assume there may be some equivalent somewhere.

Oxygen sensors I will probably just get from ebay, as it seems that people on this site haven't had too many problems with them (and they are about $100 cheaper than what i can get from the parts shops!). I now know there are only 2 oxygen sensors on the car, which means it shouldn't be too bad replacing them.

Finally, it seems that the mechanics who last serviced it did an absolutely awful job at fixing that car, as I found the throttle body completely gunked up with sludge (which I cleaned with TB cleaner and discovered the issue with the distributor, as it was firing on 3 cylinders...). The PCV valve was clogged too, and the timing seems to be off a bit. Also the thermostat is completely stuffed. Idle speed when I start the car is about 1500 RPM, which revs up to about 2000 RPM slowly over about 5 mins, before gradually dropping down to about 1000 RPM idle (which I know is still wrong). Anyone have an idea why it would be that high and behave like that? I have already checked for vacuum leaks and have not found a single cracked/loose/broken hose anywhere.

Sorry about all the questions, I just have limited time to fix all these problems, and I cannot get into the teameunos site to ask other australian eunos owners (it won't send me comfirmation emails, and the admin email address doesn't work).


Thanks in advance for any suggestions!

About the coolant temp sensor, there are at least two of them in the car, but I think there are three...
These are:
Two near the filler neck - Gauge sensor and Fans sensor (both have 2 wires)
One behind the other two that only has one wire. I think that's the one for the ECU.

If your bad sensor is the Fans Sensor, you can look for a replacement Thermo Resistor (thermistor) in your Electronics Shop. You need a thermistor for the same kind of values as the stock one. Then you must try it before the next stage... I mean you must be sure it works (make the fans turn when the water is hot enough). For that you can wire it up, boil some water, and measure the resistance... pretty simple.
Then you have to figure out how to use old sensor case with the new one. I've done it myself, but I'ts hard to express myself in english. So if you are interested, I'll try I little harder.
Anyway Do It At Your Own Risk!

For the distributor, check out the "hei mod" at the faq page. Its cheaper to "rebuild" your distributor. Also here at local autozones the coil costs around 80 dllrs and the hei mod costs around 20. o2 sensors, ebay should be fine. Coolant temp.. There is one for the fan, that can be wired manually as i did in my klze swap. The other one is for the engine temp gauge. I saw some on ebay for cheap. For disty nothing that a new cap and rotor cant fix.

[quote="MX3ak"]About the coolant temp sensor, there are at least two of them in the car, but I think there are three...
These are:
Two near the filler neck - Gauge sensor and Fans sensor (both have 2 wires)
One behind the other two that only has one wire. I think that's the one for the ECU.[/quote]

I have only so far discovered 2, although I have found many other small sensors I have no idea what they are, since I have never seen them before lol. The coolant temperature sensor I am suspicious of is the 2 wire one just on the left side of the engine. It is the one in front of the single wire one, which I am pretty sure is only for the dash, while the 2 wire one is for the fans I think... If I disconnect the connector for the 2 wire one and start the car, both coolant fans turn on at full speed, and when I plug it back in they turn off again after a couple of seconds or so. Where might the 3rd one be located? I am just trying to source why (other than the dead oxy sensors) the car might be running so rich.

[quote="hgallegos915"]For the distributor, check out the "hei mod" at the faq page. Its cheaper to "rebuild" your distributor. Also here at local autozones the coil costs around 80 dllrs and the hei mod costs around 20.[/quote]

I thought about doing things like this, but really for the moment don't have all that much time to get it all together... the car is currently operating, and really the only thing I absolutely *need* is the rotor, since the center part of this one is melted a fair bit... i have managed to clean it up a bit though, but I would like to get it replaced. You wouldn't happen to know how much a new rotor and distributor cap costs would you? I'm definitely thinking of getting the 2 oxy sensors from ebay, as I did find them while I was working under the car and they are relatively easy to get to.

Any ideas why the idle would slowly increase over time up to like 2000RPM when I start the car, then come back down again after a while? That one has got me quite baffled as to why it's acting so strange...