check engine light comes on

The car is a 1999 2.0 automatic. I replaced the engine with a 2.0 Tiburon correct dated engine with only 28,000 miles on it. Due to the other owner had engine problem due to over heating due to bad water pump.

Hi, the check check engine light comes on , and I scan it and the code reader shows, " no codes present ". I clear the codes anyway and the light goes off.

I am having issues with the cooling fans too. I replaced the Water Temp Sensor, and the cooling fan relay. The fans come on, just not when they should. The water temp gauge in the car works, just the needle is below the stock location.

The cooling fans both come on only a few minutes , " if that long " after starting the car. they never shut down " cycled on and off " , so anyways someone suggested it could be the ECM PCU causing the problem.

I got a replacement one and I am having the same problems with the Check Engine light and the cooling fans.

Since the fans are coming on should I drive the car for a certain mileage for the other ECM PCU to reset itself??

Could a Vacuum leak cause the Check engine light problem?

I sure don't know what could cause the cooling fan problem since I replaced everthing that could have caused it to not work.

Any Help appreciated greatly.

Very interesting.

Sounds like your scanner may not be able to pick up on that specific code.

Have you tried another scanner or possibly autozone/free place that will scan codes for you?

I would try to get another scanner or two on it.

There must be something the light is coming on for if your scanner clears codes and it goes off temporaily, but the problem sounds like a hard code - since it comes right back again.

Usually a bad sensor giving a strange reading to the computer will keep a strong code coming back every time.

This problem only started happening after the different engine was installed?

You may want to check part numbers on sensors for the two engines - maybe one is made with slightly different parameters causing the computer to be alarmed from the readings....

Please give more specifics, if possible, on how it behaved before and after the engine swap etc....

Hopefully this helps you in some way!!!

Let us all know how it goes!

Dale in Idaho

Very interesting.

Sounds like your scanner may not be able to pick up on that specific code.

Have you tried another scanner or possibly autozone/free place that will scan codes for you?

I would try to get another scanner or two on it.

There must be something the light is coming on for if your scanner clears codes and it goes off temporaily, but the problem sounds like a hard code - since it comes right back again.

Usually a bad sensor giving a strange reading to the computer will keep a strong code coming back every time.

This problem only started happening after the different engine was installed?

You may want to check part numbers on sensors for the two engines - maybe one is made with slightly different parameters causing the computer to be alarmed from the readings....

Please give more specifics, if possible, on how it behaved before and after the engine swap etc....

Hopefully this helps you in some way!!!

Let us all know how it goes!

Dale in Idaho

Hi again Dale.
Well I bought the car and did test drive it first. That has been awhile ago, but I did check everything out, the lights, air conditioner , heat, ect....

I don't remember a check engine light being on back then, but it was along time ago.

The replacement engine was a Direct replacement for both cars. Based on production dates per Hyundia and the recycler I called. Actually they asked for the production dates to make sure got the correct engine.

You had replied to the heater problem with error code p0116 also on another post.

So I will get the code read at autozone as you had asked me to do. Also have a vacuum leak at the Idle speed control valve IAC , going to replace those hoses today.

Thank you will let you know what I find out. Again, thank you for your help. Will update later by 4-17 with new info.

Yeah, see what that code is--if the CEL is on there must be a code in the system. And yeah, pretty much anything to do with the engine air/emissions etc could cause a CEL.

Yeah, see what that code is--if the CEL is on there must be a code in the system. And yeah, pretty much anything to do with the engine air/emissions etc could cause a CEL.


HI everone , no More "CEL" comming on , tigheded up the positive battery cable , and put the new hoses on the Idle control valve. One of those fixed it.