What is LIMP Mode?

[2TROLLFAM]

Found some time to troll through threads and have seen a few about cars going into Limp Mode and what to do to rectify.

My question is what is Limp Mode, how do you know your car is in limp mode and is it something to do with mods already done to the vehicle?

Seamus & Amelia are both stock standard when it comes to the engines etc. so is this something either of is should be looking out for?

Seamus - 2008 3ltr common rail diesel wagon (auto)

Amelia - 2006 4.2 turbo diesel ute (manual)

[TPC]

I believe it is when the ECU has detected a problem with the car and winds back the power to protect the engine.

[Pokey]

You'll know if you are in limp mode. No power !!!

[2TROLLFAM]

You'll know if you are in limp mode. No power !!!

Sooooo last night on my way to drop my son back to his father Seamus decided to be an ass and nearly got me run over.

Where I turn onto the highway is a very short entry and you have to floor it in order to be doing 100klms before you merge with the highway. So like normal I floored it & literally seconds before I merged i seemed to loose power, dropped back to about 70klm/ph then all of sudden it kicked back a gear, nearly hit 4000rpm and went no where - some poor bugga in a patrol towing a caravan had to hit the picks before he ran up my ass because I had nowhere to go & no way of stopping so had to merge ....

IF that was limp mode - I DONT LIKE IT!! Scared the sh&) out of me & the driver of the troll with the can (also copped some serious abuse which is understandable)

Tried to do it again on my way home on the highway - accelerated quickly, seemed fine and was at 100klms/ph in reasonable time without any issue .

He's done it once before but at the time I didn't give it a second thought because I was in the middle of no where with no other traffic and figured my foot musta slipped or something. That definitely didn't happen last night

[Chimo]

Limp mode is what happens after prostate cancer surgery!

Still worthwhile getting an annual PSA blood test if your over 40 yrs old (and a male)

Cheers
Chimo
PS sorry to digress but.......

[BigRAWesty]

Do you have a scan gauge or any sorta code reader to find out what's happening?

[2TROLLFAM]

Do you have a scan gauge or any sorta code reader to find out what's happening?

Our Service Manager here at work has a Nissan diagnostic tool at home (he's a mechanic by trade & owns a Navarra) so he's going to bring it in and at least do that side... He said it may show up old fault codes and no way of telling if it's old or new so IF any show up he'll investigate & clear them so I have a clean slate to move forward with.

He said since no lights came on dash it possibly wasn't limp mode and to let him know if it does it again...

[2TROLLFAM]

Limp mode is what happens after prostate cancer surgery!

Still worthwhile getting an annual PSA blood test if your over 40 yrs old (and a male)

Cheers
Chimo
PS sorry to digress but.......

LMFAO!!!! That's funny

[mudski]

When you experience limp mode your car will have no power, at all. The only way to get the power back is to let off the go pedal and then back on again. What you experienced, doesn't look like limp mode to me. As even if you floor it nothing will happen when in limp mode until you let off the go pedal and back on again.
Have you clean the air flow meter at all since owning the car? If not I would get some air flow meter spray and clean it firstly. Second, if you can get a hold of a scan gauge or this diag tool to plug in and try to replicate the issue, hopefully this will tell you more.
Limp mode is a safety function the ECU uses to stop over boosting of the engine. In the earlier direct injection models, this was a bigger issue, more so than the CRD's. The function is still used in the CRD models but the ECU seems to control the boost a bit better than the older Di's.

[threedogs]

Was your engine cold when this happened, or coldish

[2TROLLFAM]

When you experience limp mode your car will have no power, at all. The only way to get the power back is to let off the go pedal and then back on again. What you experienced, doesn't look like limp mode to me. As even if you floor it nothing will happen when in limp mode until you let off the go pedal and back on again.
Have you clean the air flow meter at all since owning the car? If not I would get some air flow meter spray and clean it firstly. Second, if you can get a hold of a scan gauge or this diag tool to plug in and try to replicate the issue, hopefully this will tell you more.
Limp mode is a safety function the ECU uses to stop over boosting of the engine. In the earlier direct injection models, this was a bigger issue, more so than the CRD's. The function is still used in the CRD models but the ECU seems to control the boost a bit better than the older Di's.

Thanks - I'll look into those that tomorrow at work.

I also phone our local Nissan dealer and they said the same thing that it didn't sound like limp mode so that makes me feel better.

[2TROLLFAM]

Was your engine cold when this happened, or coldish

Yeah - car had been sitting all day and this happened only 5mins down the road

[threedogs]

From memory the ECU will not allow you to "race" the motor when its cold.
I think that's what happened, try again with a warm motor and I think all will be OK.
Maybe someone else can confirm this.
BTW welcome back

[2TROLLFAM]

From memory the ECU will not allow you to "race" the motor when its cold.
I think that's what happened, try again with a warm motor and I think all will be OK.
Maybe someone else can confirm this.
BTW welcome back

Ok, thanks - I did try on my way home last night which was at least half an hour later (20mins of that doing 100 on the highway) and it was fine ..

[threedogs]

Great I'm pretty confident that was the problem.

[Sir Roofy]

great i'm pretty confident that was the problem.

think your right 3d been awhile since i had the auto but sounds right
wont let you go till reaches engine temp

[mojo53]

My thoughts exactly Chimo lol