Quote:
Originally Posted by Assimilator1
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Fastforward to today and it has gradually got worse and worse, happening at increasing engine temp and ambient temps, and at less throttle (but always up to about 1500 RPM).
The other week the engine was a needles width from fully warmed up, when a work mate asked me to rev it up (of course I was willing to oblige!  ), it spluttered (hesitated) then revved up (slightly embarrassing, lol). So it's getting to be quite a problem now.
Blipping the throttle from idle (to say 2k RPM) will replicate it, the colder the engine and ambient temps are, the worse it is. More throttle makes it worse too (obviously I don't give it full throttle when cold!).
No EML has shown, there are no engine codes (pending or current), I tried to read live data from the o2 sensors, but apparently that's not possible with these  (I used ISTA, an old version, and my work's snap on tool).
I did do a primary o2 sensors check with ISTA, and it found no problems, giving the sensors a very good score of 0.9.
I also did a spark duration check @idle, which was mostly in the range of 0.65-0.75 (which is in spec, spec 01.-1.5ms). And I checked combustion quality @ idle, which mostly was between 0.4 -1.3 (which is in range too, spec 0-5).
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I wondered if anyone else has had this, and what cured it for them? |
Expierenced same symptoms and that very odd. Replaced spark plugs, TA's (one got limp mod), fuel pressure sensor, final drive gear ratio to 4.44, later all new OEM ign.coils, 240E based software.
After that most hesitation like 95% is gone but with cold engine, colder weather, fast throttle you can expect that notorious hesitation. When fully warmed up there still 1-2% probability it will hesitate in some situation.
This is nuisance but can accept.