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I am seeing way way way way way way to many posts here where people fling around the term limp mode. Limp mode is VERY uncommon and i have only seen it about 2 times in god knows how many years. There are in fact many redundant systems in honda ecu's that provide safety nets in case of misc sensor failures. In all honesty its redundancy is one of the beauties of the honda ecu and why many people choose to use rom editing software over true stand alones. What happens inside your ecu all boils down to which specific sensors are affected.

examples

engine coolant temp sensor - fails your car will run slightly richer and you will not have vtec, why? because the ECT sensor is used in determining fuel trims thus the reason you would be running slightly richer. its a safety protocol built in to the ecu in the case of an ECT failure. and obviously vtec will not work since you must have a certain operating temp established in order for the system to be live. oh and a constant cold rev limit in some cases

knock sensor - a damaged knock sensor will not put you in limp mode. it will in fact retard your timing as a safety protocol and check back every couple revolutions to see if the problem has been corrected. same holds true if a correctly functioning knock sensor is detecting knock

o2 sensor (primary)- will not put you in limp mode. when the primary o2 fails your ecu is forced into open loop mode and will rely on the ecu's default maps that came from the factory or what would be the equal of a reset. during this time no long term or short term fuel trims will be done as there is nothing providing input to alter the trims, thus you will just run overly rich like you would on a fresh reset.

o2 sensor (secondary)- no limp mode here either, hell this one cause next to no side effect. its basically an expensive way to make sure your CAT is functioning withing federal specs.

iat sensor - will not cause limp mode, it will just ever so slightly alter your fuel trims towards the richer side to compensate for its failure

iacv (idle air control valve)- limp mode = the negatory on this one. you will just have a shitty idle

what does cause limp mode? like the real one true limp mode.... core sensor failure...distributor failures like the cyp taking a shit or loosing the rpm signal, map failure, catastrophic ecu circuitry failures that are internal. even this has a wide margin of outcomes. a map failure will cause the car to run like absolute shit but still somewhat ok. on the other hand a primary injector circuit failure will cause the worst limp mode of them all in which you will find getting up to 20mph if as difficult as gary coleman trying to slam dunk without a trampoline.

now this isnt the most technical thing ever but hopefully it helps clear up some peoples misconceptions about what limp mode is and when it comes into play and also about hondas redundant systems and failsafes for non critical sensor failures.

merry christmas
 

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here is the problem. on the way home last nite i drove through a slush puddle (half ice half water) then about 20 feet after the puddle was a stop sign when i got to the stop sign the car stalled. started up fine but when i got going started to stall again. i got home and it stalled again as i got in the driveway. i let it sit for an hour and start it. starts fine idles fine but when i step on the gas it bogs and stalls. if i step on the gas gradually it is fine and climbs like it should but if i tap on the gas it bogs and stalls. starts right back up but I cant touch the gas... i have checked the turbo it spins freely, i have checked the filter it wasn't wet no water was in the inter-cooler. checked the distributor no water in there. i have checked all plugs and wire connections and cleaned them with air hose. i put in new plugs i ordered a new msd cap & rotor and wires should be here tomorrow ( that is what i have on there now)... so i am stuck at this point and do not know where to go from here. not sure if something else got wet that i dont know about... any help would be appreciated. the car is a 98 gsr turbo. it also has an ss blaster coil. thanks


i have some updates... i didnt get any cel lights after and still none are showing. i do have an abs light 16 and 81 (cpu)... not sure if that has anything to do with it. i changed the fuel filter but did nothing( I didnt really think it was going to but tried) i did find some sort of a hint today... when i cold start it meaning first start of the day or after sitting for a while... for the first say 45 seconds... it runs fine... i can rev it and it responds perfect... but after that it is right back to the bogging and stalling. the idle is still fine no knocking noises. but still stuck. i am thinking maybe a connection... or sensor...
 

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while your changing your distributor cap, pull your distributor off an give it a twist, see if everything in there is spinning freely. might be locking up after it gets warm. :confused

other than that, maybe your o2 sensor? the first 45 seconds might be the open loop on the ecu while the o2 warms up, then it kicks over and the o2 is sending bad mojo?

just some outside thoughts...

should have started a thread too, but good job using the search!
 
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