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Hyundai Getz - Any Engine management experts out there? - apteet

I have a 2004 1.3 Getz that has done 32,000 miles.
When started from cold and driving off it hesitates on acceleration for about the first 1/2 a mile or so then as it warms up the fault goes away and it drives normally.
I hooked up my laptop to the OBD port one morning wu=hile the engine was cold..

There were no fault codes so I thought I would look at some data instead.

Here's what I found:
I sat in the car and the car's display said it was 46F outside = 7.7 C.
My OBD software was saying the car's coolant was 8C and the intake air was 7C.
I then started the engine.
The pre cat lambda voltage started off at 0.2volts then steadily dropped down to 0.03volts.
After about 30 seconds or so the voltage started acting more normally and I was getting good cross counts.
After a few minutes idling the coolant was reading 77C and the intake air 22C.
It would appear the temp sensors are ok but the lambda reads low when cold.
Apparently the ECU's run open loop when cold so in theory the lambda sensor is ignored.

Anyone got any ideas please?

Hyundai Getz - Any Engine management experts out there? - injection doc
you need to look at fuel trim data, short & long term.
Hesitation is normally caused by weak mixture, with a possible air leak, now this could be very small to only be noticable cold.
Where do you buy your fuel ? have you tried a different brand ?
You need to check the live data fior the coolant sensor to make sure it progresivley rises! sometime they seriously fluctuate during warm up and this can cause a hesitation or stalling as well.
Hyundai Getz - Any Engine management experts out there? - apteet
Thanks, what should I be looking out for in the short and long term fuel trims?
I use Shell petrol.
The car is converted to LPG but does not change over to LPG until it has been driven about a mile or 2, by which time the hesitation has gone away.
Hyundai Getz - Any Engine management experts out there? - injection doc
Furl trims won't equate correctley if it has LPG conversion.
technically they should be less than 20% ideal should be less than 5%
I would certainly check for air leaks if it has LPG conversion but I also wonder how old the petrol is in the tank? Fuel does deteriorate very quickly these days so if ts only running 2.5 miles on petrol I would think the fuel is old ?
I would empty the tank & try fresh fuel with a fuel cleaner first.
Hyundai Getz - Any Engine management experts out there? - apteet
Ok, thanks,

I checked the fuel trims earlier, the short term was +14.9%
the long term was -15.6%

I have no idea what fuel trims are though!
 

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