bluehatch

PM sent, thanks for your time and the offer. Looking forward to the information.

That is good news about the CTS. I will test mine out as Cougar suggested, then head for the junk yard. I am in the process of replacing the heater core right now but when I get it back in and hooked up. I will replace the ECU and see what codes it is reading and continue on this process.

Cougar, Thanks for the insight. I will check the resistance in the sensor for the gauge. It seems that I could also check the resistance in the sensor for coolant temp that connects with the ECU. Do you know where that sensor is located in a ea81 engine? I will also start to look for the service manuals, that is a great idea that had not thought of. I will defiantly have this car as long as it runs, Ergo I will also be working on it a lot in the future. After, I check out the resistance like you mentioned I guess my next step would be to find a new dash cluster. I was considering just buying an aftermarket external temp gauge and bypassing the sensor, because of the price on a new thermo sensor. Is that a bad idea if the computer is getting information faulty imformation? Or did I understand you correctly and there are TWO sensors. One for the gauge and one for the ECU. Joe

Thanks so much for the posts. But this leaves me with the question, how important is the ECM?. Can I take it out and be fine for daily driving? I know that it deals with emissions. But I also thought it participated in controlling the air/gas mixture. I also tried oiling the speedo cable. But it still does not function properly. Not sure what to do next with that.

Sorry about that, I incorrectly said ECU when I meant ECM. And it is the ECS light that always comes on in the dash.

I have a 86 Hatch 1.8. The car is generally in great shape but came with a few issues that I still have not been able to work out. Such as the gauges. There are other problems as well but I have been unable to discover the causes. The speedo gauge is hyperactive, as i accelerate it quickly dials up and by 15mph or so is pegged at 85+ and stays there until I drop below 15mph(I guess). Thankfully I've only gotten one speeding ticket. I generally just follow the flow of traffic, however there is not always some one to follow. Lol My Tacho seems to work fine until it reaches 3500+ then it starts jumping all around. Not sure what the issue is here either. My Temperature gauge has only registered a temp a few times. Otherwise it never reads any temp at all. This is the one that worries me the most. I have replaced the thermostat but it did not fix it. I priced out a thermostat sending unit. But it seems cheaper just to but a new aftermarket gauge in and bypass the old. I was told when I bought the car that the ECM did not work properly. (this was the reason given for why the speedo did not work) The story was that somehow oil had gotten on it and disrupted its normal function. A new one was installed but did not help. So at this point the as when I bought it ECS indicator light in the dash is generally on, and sometimes the EGR light. The engine seems runs rich, and I get 23mpg regardless of what how or where I am driving. So in brief, i'm not sure where to start or how these issues relate to eachother. Please Help. Joe