throttle problem

[wayne8]

Hello

I am having a problem with the throttle when you apply throttle it seems to be holding back when it first started it was most noticeable at higher speeds but now it is at all speeds.it seems a bit worse when first started you feel it holding back then it will pick up then hold back again please can you tell me what could be a common cause of this thank you.

Forgot to say its a 98 1.3mpi felicia

[wayne8]

Hello I am still having problems.I read about cleaning the throttle body which part do you actually clean.and on the throttle body there is a plug for a sensor then under that on the inlet manifold there is another plug going to a sensor can someone tell me what this is called and what its for because when I unplug it there seems to be no difference when the engine is running.

thank you

[anewman]

Thought I might add my unknowledgeable response

I have been reading about cleaning the throttle body.

As I understand it, you clean the bit that moves when pressing the accelerator pedal using carb cleaner (visible under the air filter box). One suggestion I have seen is to use an old toothbrush to get all the gunk off and this can be done with the throttle body left in place, and to clean the edges and the reverse side taking care not to let anything drop in or get your fingers caught in etc.

I could be entirely wrong though, but I am interested in cleaning my own throttle body as a preventative measure in the near future.

I wonder if the problem could be something else, perhaps valve clearances need setting? (Again I don't know if the MPI engine has hydraulic ones that cannot be adjusted as my experience is of the SPI).

[harryhill]

Hi

The throttle butterfly will likely need cleaning. All i do is spray away with the engine running. I know you are meant to be careful but im not!!

The sensor you are unplugging sounds like the MAP (manifold air pressure) sensor. If you are unplugging this and there is no difference i would suspect a problem with this although because your car is idling there is little change in the manifold pressure. The MAP sensor will communicate with the ECU and in simple terms is one of a number of sensors that communicate to keep the car running efficiently and smoothly.

If a sensor is not communicating properly then this will affect the running and with a MAP sensor especially so under load.

I would try cleaning the throttle body and then unclipping the MAP sensor and cleaning the connector and pins on the sensor with a cotton bud and electrical contact cleaner as it is sometimes the case that the connector and pins corrode causing a poor connection. This shows up as a green substance.

Other possibilities contributing could be that your tappets are way out

[pinkskud]

is it not a MAF (mass air flow) sencer on the felicia???????????/

once you have skrubbed the the throttlebody with a tooth brush, and the sencer plugs with a wire brush. you should un-plug the battery over night, then in the morning re-connect the battery,and turn the key till all the dash lights come on (one step befor ignithin). leave the key in this possition for two min's. them start car as per normal.

hope this helps.