High fuel trims

[Jurassicspark]

Vauxhall Zafira with high a$$ fuel trims.
During idling fuel trim is around 31% which sometimes drops down to 0%. Long trim is on 20 percent fixed. Car runs fine with no problems at all. Any suggestions?

 

[carmanmemoranda]

Vauxhall Zafira with high a$$ fuel trims.
During idling fuel trim is around 31% which sometimes drops down to 0%. Long trim is on 20 percent fixed. Car runs fine with no problems at all. Any suggestions?

Do you have problems with the car or just looking for some ?

 

[Jurassicspark]

Do you have problems with the car or just looking for some ?

No problems at all just a little high idle for the first 20 minutes of driving the car, that's it really... I just want to know why my fuel trims are so high without any noticeable clues

 

[carmanmemoranda]

No problems at all just a little high idle for the first 20 minutes of driving the car, that's it really... I just want to know why my fuel trims are so high without any noticeable clues

What do you call high idle ?

 

[Jurassicspark]

What do you call high idle ?

1300rpm

 

[carmanmemoranda]

After cold start and until it warms up ? Or other?

 

[Jurassicspark]

After cold start and until it warms up ? Or other?

After it warms up

 

[carmanmemoranda]

Checked all the obvious basics 1st? Coolant level, oil level?

I'm assuming you have a diag tool to get the fuel trim figures. How does warm up cycle go in relation to the rpm?

 

[Jurassicspark]

Yeah checked all basic stuff.
Will need to check that next time

Things that is confusing me is that sometimes the FT's would be low and sometimes it will creep up to 31%. If it take to a garage the mechanic would say its fine (based on my rpm, which goes to 800 when warmed up) these mechanics dont look at scanners.

 

[carmanmemoranda]

Yeah checked all basic stuff.
Will need to check that next time

Things that is confusing me is that sometimes the FT's would be low and sometimes it will creep up to 31%. If it take to a garage the mechanic would say its fine (based on my rpm, which goes to 800 when warmed up) these mechanics dont look at scanners.

Don't they?

Usually they are given a problem and then work out how to solve

You currently don't have enough info to work from

 

[Belle427]

Ideally short term will cycle around 0 plus or minus 10% in an ideal world. Plus is adding fuel.
Maybe you have an air leak if idle is high.

 

[Nige F]

Perished vacuum hose somewhere ?