Since I had the thermostat replaced I have not been too happy with the performance of my felicia (1.3mpi w reg)

The replacement temp sensor came with a yellow collar instead of the blue one that was already in it. At normal running temp the gaugue now reads just over the half way line previously it was just under and it now seems to get much higher when stationary, the fan kicks in when the line hits the bottom of the zero on 110, so about 98 degrees i reckon. Now this could be because the old thermo was dying or that the old temp sensor was shot but I could so with some confirmation, yellow or blue??? mpg is also slightly down to about 40mpg.

Also the car doesnt always accelerate smoothly, put my foot down and there is a pause then a jerk of acceleration, like wise when i take my foot off the engine braking isnt smooth. Im thinking the throttle body may need adjusting?

I also have a rattle when I start the car, when I put my foot down on the clutch it dissapears though - clutch release bearing???

Thoughts on my diagnosese please.

Id say your current thermostat is correct, your ecu is probably adjusted to the old one, Im not sure if the MPI cu can be reset by disconnecting the battery for a period of time and reconnecting? Not a bad idea though to clean the carb and check plugs and filters etc.

Haynes Manual does say that disconnecting the battery resets the learned values, might try it.

Does the ECU constantly adjust its learned values or once they are set does it just stick with them?

IF you have to reset them by disconnecting the battery Id suggest that it sets up initial values and sticks close to them. It might do an initial big setup and then small modifications from there on or it might just do a big setup and stick with it. Im not sure, My best guess would be an initial setup and small adjustments from there. That would work well to adjust to an engine whos running conditions change slowly between services etc.

The best way to reset / adjust a cars running logisitcs is to give the vehicle a good run out on a fastish road like a motorway which will enable a basic ecu the time to monitor and analyse and set fuel, ignition, crank timings. What you want to achieve is normal running temp with as little as possible stop / start traffic.

The best way to reset / adjust a cars running logisitcs is to give the vehicle a good run out on a fastish road like a motorway which will enable a basic ecu the time to monitor and analyse and set fuel, ignition, crank timings. What you want to achieve is normal running temp with as little as possible stop / start traffic.

surly going through the rev range would be best, as the ecu can then see whats happening throut the engines range, and ajust acordingly?

only a guess, correct me if (as usual) i'm wrong.

are we talking about disconnecting the bat first or just running it down a motorway without doing a thing?

Thats all i do, manchester to liverpool and back 5 days a week

disconnect battery first then drive it down the motorway first trip to let it get new values. The bonus there is that this is actually your normal driving and so will help it learn your actualy patterns better.

would you sugest this after adding mods. say induction, can or exhust.

It could well help. Not something Ive thought about much felicia modified the most had a SMS ECU and was rolling roaded regularly to test small mods etc. Might be worth a try to see how things adjust. I suspect that the Lambda sensors automatic modifications of fuel mixture would be enough for minor exhaust and airfilter mods, no idea though if a ECU reset might help further etc.

will try the ecu reset this weekend as thats the cheapest, then maybe some stp and a change of the filters, then a fabia.

will try the ecu reset this weekend as thats the cheapest, then maybe some stp and a change of the filters, then a fabia.

How did it go GeoffStone?

Did u reset the ecu by diconnecting the battery?

My 1.3mpi felicia is using too much fuel (see my seperate post), would diconnecting battery help with my excessive fuel consumption?

Thanks.

i wouldnt be any where near qualified enough to answer that question but I still have a rough running felicia.

There are two problems I have.

1) When she idles she is all over the show, very lumpy, this is worse at running temp

2) she kangaroos about abit when lifting of and putting down the accelerator, there is no smooth deceleration or gradual acceleration, its all or nothing. Again worse at running temp.

Im going to get it in after payday but these are the things I have been advised to look at from some of the experts here.

Fuel Pressure Regulator

Check the inlet manifold gasket for leaks

I also have a noisy clutch so I need to check the thrust bearing in the clutch , or the release bearing, im such a novice

2) she kangaroos about abit when lifting of and putting down the accelerator, there is no smooth deceleration or gradual acceleration, its all or nothing. Again worse at running temp.

normal.

normal.

then mine is abnormal :confused:

normal.

I think not, my good man.

the 1.3mpi should be supersmooth throught the rev range.

possibly sommat to do with the fabled "throttle body" issue?

Normal???? Really?!!!!

I refuse to beleive that. Its not like its an old engine (2000, 31k mls), when im in traffic jams im borderline whiplash.

The fabled throttle body issue being that it just needs a clean or adjusting???

i'v had two moters with a 1.3 spi (yes i know yours is an mpi) in them. and both had this prob. thats not to say it cant be cured, i just never bothred (cuz i'm fat).