Freescan and Diagnostics 101

[Rick Edwards]

The starting point for this thread is the idiot (i.e. me), a badly underforforming car, a computer and some software. After much swearing and strange looks from passers by with a netbook in the car I have managed to get the car to talk to the computer and produce some data logs which I have attached.

This is as much use to me (the idiot) as a handbrake in a canoe, although I have managed to work out the basics such as rpm, speed, temp etc. What I DO know is that I am not going very fast, and after some help from the mighty Bibs we now know that the car thinks I have a very light right foot and I never give it more than about 69% throttle.

The time has come to ask for help!!

HELP!

I realise that there are several problems afoot here. I am of low to medium ability with a spanner but willing to learn fast (or at least faster than the car)

So I throw myself on the mercy of the forum.

thanks in advance

[Bibs]

Does Freescan show any error codes? Have you checked the sensor diagnostic tab to make sure all the sensors are working?

Throttle Position Sensor: Typical Values, 0% = 0.5V, 100% = 4.5V

Coolant Temp: Typical Values, 37

[sailorbob]

Not sure what you are asking for people to look at in there. It looks like a warm up from cold and finishes when the engine is just up to temp. I would hope that you wouldn't be lead footed until its warm and remember that the oil takes longer to get up to temp too, especially if a thermostatic oil cooler take off plate hasn't been fitted.

Edited September 11, 2009 by sailorbob

[Jonathan]

You want the freescan manual from LEW. Sadly it's a paid item but it is worth the money if you want to know what's going on with the car.

[Rick Edwards]

Does Freescan show any error codes? Have you checked the sensor diagnostic tab to make sure all the sensors are working?

Throttle Position Sensor: Typical Values, 0% = 0.5V, 100% = 4.5V

Coolant Temp: Typical Values, 37

[CarlC]

Hi Rick,

It will be very difficult for us to assist with understanding what the issue are with this log file. As has been said it appears to be a warm up cycle of the car. TPS hardly ever hits about 40%, car temp is under 80 until the end of the log. Speed does really get above 40mph, rpm max is around 4000 and there is almost no boost being generated.

We really need a log file to cover acceleration through the gears and TPS in as much as the range as possible. This can then be compared to other logs from known correctly performing standard cars. Basically get the car under load so we can see how it performs. Unless there was something significantly wrong with one of the sensors then thats about all we could check from this current log file.

Edited September 22, 2009 by CarlC

[Rick Edwards]

The revs not going above 4000, max speed 40 and the lack of boost was exactly the problem...that was as good as it got...not the blisteringly nissan micra leaving performance I was expecting. In fact I was being passed by a procession of small cars with kids laughing.

I had to get some things done that were way beyond my spanner level by someone who knew what they were doing so I got them to look at the problems for me. (Lazy I know but heh I want it working)

It turns out that the boost capsule was knackered and the turbo was not spinning as it should either. Also the fairly predictable impeller in the charge coler was shot as well. As I want it all to be right I have hit the plastic and elected for a re conned turbo and a new impeller in the CC. I guess its a cop out getting it all done by someone else but to be honest I would not want to mess it up this early into my ownership.

Hopefully I can re connect the car to the computer this thursday and post a log of faultless figures that everyone can go "oooooh" and "thats nice" to rather than the tooth sucking, "that looks expensive" sound I am used to.

Thanks for the help so far and I still have no real idea about what I am looking at on freescan apart from the virtual dash, which I do understand. I am thinking that the manual may be a good investment. ??

[lotus4s]

The Freescan manual is a great investment, get it...

[CarlC]

Freescan Manual is well worth the purchase. If you haven't down loaded the parts/service manuals then these are also invaluable for finding the sensors and assisting with fault finding, assuming your a paid member of the forum.

First easy thing I'd recommend to check is the MAP sensor line that runs from the back of the engine just below the back of the charge cooler - If its connected. Its a thin hard black plastic pipe that has a rubber elbow to connect to the engine and runs across to the right hand side tank cover to another rubber elbow and attaches to the MAP sensor.

Just do a search for MAP sensor, there should be plenty of threads on this problem. Cause the car to struggle and stumble under any sort of load. Its also really easy to fix.

Let us know how you get on.