Limp Home Mode

JUZXR8 · 12-05-2006, 11:09 AM

Hey guys,

i did a search but i cant really find the info im after, i want to know how u can tell if it is in limp home mode yourself.

the engine is runnings like a bag off balls eg, searching for idle, it is picking up really slow n takes for ever to get anywhere and it wont go into top gear, there is nothing wrong with the tranny apart from it needs a service. Im pretty sure it is im LHM but i wanted other peoples opinions.

Thanks Guys
Juz

mcflux · 12-05-2006, 11:10 AM

I'm not quite sure on what happens to the engine's tune whilst in LHM, but the transmission (if auto) stays in 3rd gear.

JUZXR8 · 12-05-2006, 11:14 AM

does it stay in 3rd gear only? because it goes from 1st 2nd into 3rd on takeoff n just doesnt hit 4th

mcflux · 12-05-2006, 11:24 AM

That could be a lockup issue instead, which I *think* may be the S7 solenoid. I'm going on 2nd-hand information here.

**Professor Farnsworth** · 12-05-2006, 11:26 AM

My understanding of limp home mode was it STAYED in third gear regardless, and didn't change up OR down, could be wrong though.

JUZXR8 · 12-05-2006, 11:28 AM

Quote:

Originally Posted by fantz

My understanding of limp home mode was it STAYED in third gear regardless, and didn't change up OR down, could be wrong though.

thats what i thought aswell, but my mechanic is telling me that it is in LHM and htat ive probly got a wiring problem from the engine swap

mcflux · 12-05-2006, 11:29 AM

Yep ;) takeoff in 3rd, cruising the highway in 3rd...

EDXR6T · 12-05-2006, 11:35 AM

if ur changing thru 1st-3rd ur not in limp mode

mine was in limp mod cos the speed sender shat it's self

but on start up it b fine for a few sec's then bk in to LHM mode
LHM dosent affect the way the engine run's so if he's trying to pin it on LHM he's talking sh1T!

**Professor Farnsworth** · 12-05-2006, 11:43 AM

I think from the AU onwards there was an engine-related LHM, where the cylinders would gradually shut down ? Not sure about before that though, think it was just restricted to trans problems.

Also sorry Ghia5L, didn't see your post, so mine was a repost ;p

:

mcflux · 12-05-2006, 11:46 AM

Quote:

Originally Posted by fantz

I think from the AU onwards there was an engine-related LHM, where the cylinders would gradually shut down ? Not sure about before that though, think it was just restricted to trans problems.

Also sorry Ghia5L, didn't see your post, so mine was a repost ;p

:

No probs, just don't do it again or I'll ban your *** from the internets! I have powerful owl friends...

-jjM- · 12-05-2006, 11:52 AM

Quote:

Originally Posted by Ghia5L

No probs, just don't do it again or I'll ban your *** from the internets! I have powerful owl friends...

**Professor Farnsworth** · 12-05-2006, 12:42 PM

hahah

Juz Gremlin: i'd take the car to a decent/different mechanic if i were you, take it to three if you want a more accurate diagnosis.

JUZXR8 · 12-05-2006, 02:52 PM

yeah im goin to take it to an auto elec, n mayb a transmission place....see wat the go is

thanks for the advice guys!

Holbrookau · 12-05-2006, 03:50 PM

In EFs there are 2 types of LHM - going by your symptoms, JuzGremlin, it's likely EDs have the same setup.
The first LHM is if there is a problem with the auto - it is locked 3rd, maximum line pressure is applied and the converter is left open.
The second is actually called LOS (Limited Operation Strategy) and is for PCM (Power Control Module) issues - if a malfunction occurs in the PCM:
Timing is fixed at 0 degrees
Fuel rate reduced
IdleSpeedControl duty cycle is reduced
Which would make the car have much less pickup, not idle correctly and probably run richer. Sounds like your problem..
Have a mechanic with the correct test equipment do a diagnostics check - should be able to pinpoint your problem.

Grechie · 13-05-2006, 05:06 AM

i heard engines them selves can go in limp home mode, how does this happen? wot goes wrong for a engine to do it?

Holbrookau · 13-05-2006, 10:56 AM

Quote:

i heard engines them selves can go in limp home mode

Sorry Grechie, but do you even read a thread before posting? Directly above your post is one that says exactly that..

JUZXR8 · 13-05-2006, 11:24 AM

ahhh awsome, thanks for the info holbrookau, ill make sure to let the mechanic know

Holbrookau · 13-05-2006, 12:38 PM

NP, just didn't want you to tell your mechanic that he doesn't know what he is talking about ;) By the sound of it though, he may not have the resources to do a proper diagnostic test.

megsy · 13-05-2006, 11:27 PM

what causes engines to go into limp home mode?

well i can send mine into limp home mode by revving it too much on startup ...ie without oil pressure, to fix it it's a simple case of find a flat spot with no cars on the highway, in nutrel key off then on again, if your good the engines still turning enough to fire up again without having to use the starter

Grechie · 14-05-2006, 05:07 AM

Quote:

Originally Posted by Holbrookau

Sorry Grechie, but do you even read a thread before posting? Directly above your post is one that says exactly that..

yes i didnt read it b4 i posted, my bad