Hello Everyone, I am Derick.
Hope you guys can help me.
I have a 2001 Fiat Palio 1.2 8v.

The Problem I have is that when I am driving it feels like it stick at ±2000 revs.
When I stand still it revs up but it has slow throttle response at first then after that "sticking" point it revs up no problem.

Parts I Replaced:
Set/Checked Timing
New spark plug leads
Spark plugs
oil filter
fuel filter
air filter
new oil
ALL as per spec for this model.

PS: It did this before I serviced thwe car.

It backfires through the air intake when i rev it and it has no power when i drive. I can drive at slow speed but ±70km/h is max I can go.

Any help would be appreciated.
Thanks
Derick

hi Derick,
did you remove your CAM belt when you were setting/checking your timing?

Hi alan 49, No I didn't remove the belt.
I only checked to make sure crank pulley and cam pulley aligned with their markings.

Things I did today:

I plugged out each sensor individually and started up the the car to see what effect they had and if it made a difference.

Each sensor had an effect except for the lambda (o2) sensor.
So I'm thinking it's either that or the exhaust could be blocked.

My thought is that if the exhaust was blocked I wouldn't be able to rev it past that flat spot where it hesitates.

Would anyone know which spark plugs are the correct ones for this vehicle as the ones I have in is the NGK BKR6E. According to other threads it should be BKR5EZ ???

Another thing I noticed is that my plugs are burnt black and that after only 3days.
And I haven't really driven it.
Furthest I drove was about 2km.

Any help or input would be appreciated.

Thanks
Have a lovely weekend.

Welcome at FF.
First things first: have the ECU read at a dealer for stored faults.

Derick, did you already have the problem (stuck at +-2000 RPM) before you did your service? Have you given the carb a good blast with carb cleaner? With the air intake to the carb removed, if you rev using the accelerator cable, does it rev properly, or does it also have the same "sticking point" as revving from inside the car?
(I'm also using NGK R BKR6E plugs)Do you have a multi-meter ?
Does it make any difference to your revving if you remove any of the spark plug leads?

Hi Alan49, Yes I did have the problem before the service.
It doesn't get stuck.
When driving it feels like something is holding back the car then letting go ( if that makes sense ).

Same inside and outside the car.

Yes I do have a multi-meter.

When unplugging the spark plugs individually I can hear it's not firing on that cylinder.

Ok so today I stripped the Head Off then did a complete overhaul with decoking gasket set. ( gaskets etc )
The problem still persists.

It will idle fine for a couple of minutes then starts idling low then shuts off.
When driving there is no power when engine is warmed up.

Was thinking maybe lambda sensor?
But if I plug out the lambda sensor it makes no difference at all???

Could it maybe be one off the throttle body sensors???
IAC valve or TPS or Air Temp Sensor...

I have noticed that the thin pipe on the throttle body is plugged up with a screw and not plugged in on the air intake pipe. Could this create an issue???

Also there is some signs off over-fueling such as small puffs of black smoke when i rev it a bit hard and spewing black s4!t out the exhaust and slight backfire out the exhaust when revving it multiple times in a row.

Thanks for the replies and the help. Much appreciated.

Thanks
Derick

Hi Peter Pick-Up.

I've taken it to the garage to get the ecu read but no faults are logged.

Thanks
Derick

It seems to me that the timing is of, so have a closer look at that.

Hi Peter Pick Up, checked timing over and over. It's 100% .
Tomorrow i'll test the tps, lambda sensor and air temp sensor and do a vacuum test on map sensor.

Basically i'm just going to test all the sensors.

Will let you know if I find something.

Thanks
Derick

hi,
i have also had the same problem with my fiat palio 1.2,
i have been told that it was the timing mostly,
from personal experience i now know that this vehicle will not start at all with the timing off, i have a back firing problem and it happns all the time, all plugs and leads and coil pack have been checked,
will be replacing complete exhaust system next

is the little pipe you are referring to around the back of the carb? My one is also blocked with a screw, and it hasn't done me any harm. I would remove the IAC and spray it clean with carb cleaner(mine was gunged up). By the way, a new IAC valve costs R3450.00 at Fiat in Craighall Park. (You can live without one though, if that turns out to be the problem.)When trying to fix my Palio I priced the TPS as well - R2750..

Hi All, So I figured out the fault in the end was the o2 sensor.
Will keep you guys updated if anything changes sofar so goo.

Btw, you can purchase a complete throttle body for R3450 including all sensors

Thanks
Derick

So did you replace it?
Fiat demands for the Palio an O2 sensor change every 120.000km, according to the handbook..
Mine failed around that time as well, with only slight hessitation, somewhat raised fuelconsumption and sometimes stalling as result.

Good Day All.
So I replaced the lambda sensor and all is fine.
Only problem I have now is a slight hesitation on acceleration.
It hesitates on about half throttle put if I put foot then it hesitates about 2 seconds then it goes with ease.
Will check timing again tomorrow.
Anybody know on how many degrees the crank should be set?

Thanks
Derick

hi Derick, I'm glad you're sorted out. How much did the lamba sensor cost, and where did you buy it from?

ThePalioGuy said:

Good Day All.
So I replaced the lambda sensor and all is fine.
Only problem I have now is a slight hesitation on acceleration.
It hesitates on about half throttle put if I put foot then it hesitates about 2 seconds then it goes with ease.
Will check timing again tomorrow.
Anybody know on how many degrees the crank should be set?

Thanks
Derick

Click to expand...

hi,
good to hear it's running again,

thought you'd checked the timing marks previously..??

Bought the lambda sensor from Midas R 495.00 it's a universal one so you have to solder the wires onto your existing plug.

So I thought it was all sorted but now I have the issue of the car feels like it lags on acceleration. Any ideas as to what can cause this?
And yes i've checked the timing a million times with correct tools.

Thanks
Derick

I don't like universal (O2) sensors.
Why didn't you buy an original NGK or Bosch sensor ( of Ebay.com....)?

Hello.
Ok so now the issue is the car hesitates on acceleration and then it feels like it releases and it goes no problem. My fuel consumption is very poor. Any thoughts or ideas would be aprreciated.
By the way I got the OEM Lambda Sensor and installed it today no difference.

Thanks
Derick

Did you find problem with hesitates on acceleration my 12 dose the same