306 Xsi Hesitant Under Throttle?

[DaveW 6]

My 2.0 8v has started being hesitant under throttle it does it cold and sometimes warm like after popping to the shops for a few mins and going back home it does it all again any ideas to help me please?

[Mikey S 29 1 Cars]

My 2.0 8v has started being hesitant under throttle it does it cold and sometimes warm like after popping to the shops for a few mins and going back home it does it all again any ideas to help me please?

 

check the lambda sensor is switching. ive seen a few that are 'stuck' and they cause a miss-fire. that, or check the coolant temperature sensor is within its limits. the haynes tells you how to check them both and it should give you the values as well.

 

mike

[DaveW 6]

Ah yes how do i check that? you just reminded me that the engine light came on today too but went off after 20secs.

[Mikey S 29 1 Cars]

Ah yes how do i check that? you just reminded me that the engine light came on today too but went off after 20secs.

 

 

theres 4 wires on the lambda sensor. 2 are heater wires and the other 2 are signal wires to and from the ecu. on the heater wires there should be 12vs with the engine running. the signal wires will switch a voltage somewhere between 0.2 of a volt and 0.8 of a volt. it should be a continuous switch.

 

iirc there are 2 grey and a 2 white wires. usually the greys are heaters and whites the signals. just backprobe the two greys and the two whites and see what you have going on. if its stuck on a high voltage (0.8 of a volt or thereabouts) the mixture will be stuck weak. low voltage is opposite (rich).

 

mike

[carbers205 1]

Dave if the ecu light has been on then you can check it yourself with a length of wire and a switch! The instructions are here and the codes are here. Ive used this method a few times and it does work

 

Andy

[ablister 31]

my first xsi needed a new map sensor as it suffered from the same symptoms: jerky/lumpy when trying to pull off?

[DaveW 6]

Interesting stuff, yep jerky and lumpy! might give all this a go then see what happens thanks.

[DaveW 6]

Would anyone know where the map sensor is on the inlet?

[NeilGTi85 5]

This is where it is on the GTi6....not sure if its the same on the XSi though...

[ablister 31]

map sensor is away from the inlet near to the os strut. It's bolted to the side and is next to the fuel lines/throttle cable. The pipe runs from the end of the inlet manifold next to throttle body, if you follow that it leads to the map sensor

[DaveW 6]

map sensor is away from the inlet near to the os strut. It's bolted to the side and is next to the fuel lines/throttle cable. The pipe runs from the end of the inlet manifold next to throttle body, if you follow that it leads to the map sensor

 

Got it! thank you. Now i just need to find a spare one...

[Alastairh 47]

Double check the pins for all the inlet plugs are good condition or any damaged wires.

 

Freind of mine had similar issues. But likely to be map / lamba.

[carbers205 1]

Dave Ill check in my garage in the morning now I know what Im looking for

 

Andy

[DaveW 6]

Lambda sensor is buggerd! i unpluged it today car runs fine now but really need to get another one sharpish...

[carbers205 1]

God Id forgot all about your MAP sensor mate, guess it doesnt matter now!

I paid about £65 for the lambda on mine just for reference, and dont get a universal one, apparently they just arent worth it.

[Mikey S 29 1 Cars]

Lambda sensor is buggerd! i unpluged it today car runs fine now but really need to get another one sharpish...

 

 

dont buy a cheap sensor. get an ngk/ntk one. there miles better.

 

mike