Throttle body?

[cjcrumly]

Hi, I have, what is at the moment, a small running problem with my '98 Felicia 1.6Glxi and just wondered if anyone has any suggestions.

Not sure...but I think the problem may have started when I had to replace the rear exhaust section and drove it for a few days without this piece fitted while I waited for the new part.

Now at certain times when I declutch approaching junctions, etc, the revs drop down quite low (about 400-500) before picking up again to the correct idle (about 700). The car doesn't quite stall but it seems like the problem won't get better and eventually it will start to do this.

I have checked the resistances of some of the sensors which seem to be OK - in particular the coolant sensor but also some of the resistances for the throttle and MAF sensors. The plugs are new and I can't find any obvious air leaks. I have a basic hand-held code reader/ reset device which doesn't report any error codes.

Wondering if it is a problem with the throttle body? I have read some posts that suggest a clean/ basic settings reset can often cure such problems but am not sure what this involves. I assume this requires specialist diagnostic equipment?

I am concerned about removing the throttle body to have a look if setting it back up again is beyond DIY scope.

Or should I be looking elsewhere?

Grateful for any suggestions/ comments and many thanks in advance.

[TeflonTom]

did you check the lambda probe?? driving with a piece of the exhaust missing would give funny readings to the ecu from the lambda probe

[TeflonTom]

oh yeah, just another thought on this, forgive me for stating the bleedn obvious but have you checked the throttle cable adjustment??

[cjcrumly]

Many thanks for the suggestions....

I have just checked the lambda probe....fluctuating from approx. 0.05V-0.75V in about 1 second. From information googled this seems to be OK although maybe slightly sluggish and dropping a little low.

Throttle cable adjustment also seems OK.

I have noticed a small leak in the joint of the rear exhaust section I fitted..I will get this gas tight first and then maybe look at the throttle body if there is no change.

[cjcrumly]

Problem solved at no cost and a couple of hours time (my time=no value)

Just cleaned the throttle plate (and surrounding bore) in-situ using a clean cloth and a small amount of saliva.

Most of the carbon deposits could be removed by rubbing. I wrapped a small flat-bladed screwdriver with the cloth to carefully scrape away the harder to remove deposits....care is needed not to damage the alloy.

I found that by holding the throttle open you could get to the back of the throttle plate and the sides of the bore. Also important to clean the perimeter edge of the plate.

I have attached a couple of photos after cleaning but unfortunately I didn't take any before.

The idle now seems perfect and drops steadily to 700rpm without dropping below/ stalling...also now steady as a rock where there were very small fluctuations before. The response at small throttle opening has also much improved.

Hope this helps anyone looking to save some money.

P.S. For information the car is just approaching 90K, so may be worth noting this as a potential problem at this sort of mileage.

[TeflonTom]

that is one very clean throttle body! well done fr getting it sorted and saving yourself a few squids

[ncarring]

Carb cleaner makes a good alternative to saliva - but don't get them mixed up - it doesn't taste nice I use that cheapo spray engine cleaner that you get in the pound shops - smells like white spirit but I'm not fussy.

[cjcrumly]

Many thanks..this was one of those rare satisfying 'no cost' jobs that seems to make a big difference.

I'm sure carb cleaner would be a better alternative....although I was bit wary of any chemicals getting past the throttle spindle into the control section.

Saying that however, my saliva could possibly be more harmful than the carb cleaner!

[ncarring]

If you're worried about it getting where it shouldn't (and remember the normal environment for the throttle body is a petrol vapour) spray it on the rag instead of into the opening

[cjcrumly]

Yes...I was probably thinking of some of the other more agressive solvents available that may be harmful.

I'm sure though (as implied) that carb cleaner is probably petrol based and perfectly safe to use.

It's difficult to know what effects some of these chemicals may have on some of the sensitive components fitted to modern engines.

Many thanks.

[johnh510]

It's worth taking great care with cleaning agents in the throttle body, I'm fairly sure I finished mine off by being a bit too enthusiatic with a spray cleaner applied direct "down the hole".

Put the cleaner on a cloth and use that in the bore of the throttle body and on the edges of the butterfly valve.

[TeflonTom]

"pfffft" just spray brake cleaner in there!!! do it while the engine is running

[dara]

i cleaned my throttle plate with a couple of baby wipes ..........2 years of stalling finished HAPPY DAYS WAS GUMMED UP WITH OILY THICK BLACK STUFF WORKS PERFECTLY NOW I CAN'T THANK YOU ENOUGH CJCRUMLY

le meas

dara

[M4tthew]

I had the same problem and this solution worked for me too - very, very pleased!

It is a bit of poor design - I noticed that the tar is due to the a pipe from the rocker cover which presumably vents the top end of the engine. I'd call that a design fault.

Cheers Cjcrumley!

[pinkskud]

took the body off mine yesterday and cleaned it with thinners. put it back together and now at idle the revs flutuate from about 900 to 1100 at about 2 second intervals.

any ideas?????

[TeflonTom]

needs resesting mate!

[harryhill]

did you put a new gasket on as it sounds like a leak

[KenONeill]

I had the same problem and this solution worked for me too - very, very pleased!

It is a bit of poor design - I noticed that the tar is due to the a pipe from the rocker cover which presumably vents the top end of the engine. I'd call that a design fault.

Cheers Cjcrumley!

That's actually more by way of a "poor bit of emissions control legislation". Replace it with a small cotton gause filter (rocker cover end) and a blanking plug (air cleaner end). This is legal on the aftermarket, but not on a new car!!

[iansmith]

That's actually more by way of a "poor bit of emissions control legislation". Replace it with a small cotton gause filter (rocker cover end) and a blanking plug (air cleaner end). This is legal on the aftermarket, but not on a new car!!

Hi

Where to obtain filter and blanking plug ?

[TeflonTom]

Hi

Where to obtain filter and blanking plug ?

you can get the little breather filters off ebay for less than a fiver:)

[KenONeill]

And blanking plugs from most car accessories shops, or some motor factors.

[iansmith]

you can get the little breather filters off ebay for less than a fiver:)

Thank you, I didn't know that.

eBay.co.uk - breather filter, oil breather, oil catch tank, Car Tuning Styling items at low prices

[iansmith]

:chef:

Bunged it up.

Kitchen Scourer Metal wool stuff stuffed down there.

Wot about the MOT test, would they fail it ?

[KenONeill]

Not a problem as long as the exhaust sniffer gets the right figures (which is more likely with no oil going down the inlet).

[iansmith]

Passed the MOT today :hooray:, first time:hooray: , no fails :clapclap:.

Nreg 1300 felicia.

43k miles, done 15k since the last one.

Plugs, airfilter, leads, Oil change, tracking during that time

Now doing 50+mpg.

Does anyone know what these emission figures mean ?