Stumble before engine is up to temp

[Screwdgie]

I have only had the lund 93 tune on my car for a few weeks. I have noticed that before the engine is up to temp, the car feels like it stumbles, almost like a slight misfire. Once the CHT gets up to 185 or 190, the issue goes away. I never go about 50% throttle before it is up to temp either.

Never any issues with WOT, have sent in logs and was told everything looks good there.

I have monitored different PIDs while driving before the car is warmed up and don't see anything out of the ordinary. I can try to datalog the issue as I am sure that's what many will recommend, but it doesn't happen every time and only for a short period of time on my way to/from work while the engine is coming up to temp.

I have tried different gas stations and it doesn't seem to make a difference. I'm almost tempted to uninstall the tune at this point, it is such a nuisance.

Wondering if anyone else has encountered the same thing?

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[benni302]

Someone correct me if i'm wrong, but i'm pretty sure this is a protection feature from the factory until the oil pressure is at normal operating range. It happens in mine too and the powertrain is stock.

 

[Jay-rod427]

Mine does it too, even with light acceleration.

 

[Evil Minion]

Ditto, I've had this since day 1, until the car is up to temp. Still stock engine wise, no issues in 17k miles...

 

[Screwdgie]

Hmm I don't recall mine doing it stock. Well if it appears to be normal I'll just live with it lol

 

[v8440]

I can't imagine a scenario in which an engine would be made to stumble for self protection. My guess is you guys have some of the many cars that left the factory with plugs gapped too wide.

 

[Screwdgie]

I thought about maybe the plugs being an issue too, but I would assume the issue would arise under heavier loads also

 

[UPRSteve]

Your windbands are stock in open loop and not up to temp yet. They need heat to read correctly. A good temp is anything 160 plus.

 

[HISSMAN]

I just started noticing this the past couple days. Mainly because I have been in a rush. So a thermal protection mode sounds very plausible. I was about to start testing COPs and plugs this weekend.. Good to hear that it is normal.

 

[Derek@Lethal]

My car does it too. Stock, tuned, etc, doesn't matter. Actually, just about every Mustang I've owned has done it for the reason Steve@UPR stated.

 

[Screwdgie]

I also thought that could be it, but since I never personally noticed it with the stock tune I thought it may be tune related. Good to know I don't have to start digging for an issue that isn't there

 

[Jay-rod427]

Your windbands are stock in open loop and not up to temp yet. They need heat to read correctly. A good temp is anything 160 plus.

HAHA! Widebands*, stuck*...lol

 

[HISSMAN]

 

[Gibbo205]

Mine did this too on stock and SCT canned tune. Now on JDM tune and car is like butter smooth even when cold.

 

[IowaPony]

I have this issue with my tune as well. Never had it until I put the GT350 crap on. Now I get told my tune looks fine, but yet I have to let my RPM's drop under 1k before I can even so much as touch the throttle. There's a lot more wrong with it as well, but Lund refuses to work it out in the tune, so I'm stuck with a crap tune with tons of surge throughout every gear. I'm not one bit happy with my Lifetime Tunes. Good luck!

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